Investigation of Indoor Climate in a Naturally Ventilated Office Building

DEFF Research Database (Denmark)

Larsen, Tine Steen; Kalyanova, Olena; Jensen, Rasmus Lund

2008-01-01

A measuring program in a naturally ventilated office building in Copenhagen was carried out to document the indoor climate and ventilation system performance during a year. It included a questionnaire regarding the perceived indoor environmental quality and physical measurements of thermal comfort...... to a combination of poor control of solar shading and a very high local heat load that was above the Danish recommendations for naturally ventilated office buildings. Both measured and perceived indoor air quality in the building was in general very high. The measured air flow rates was relatively high due...... to the need for cooling in the office building, while the level of infiltration was quite low indicating an airtight construction....

Ventilation and filtration of active buildings

International Nuclear Information System (INIS)

Chapman, E.J.

1975-12-01

Over the last twenty years considerable practical experience has accumulated on the ventilation of buildings handling radioactive materials. It has been recognised that there is a need to establish a UKAEA code of practice in the light of this experience for the future use of designers and operators in this field. An attempt is made to lay down some of the principles governing the design of ventilation systems and, from the existing background data, to establish some of the basic design criteria. (author)

An Evaluation of a Proposed Ventilation System for Melbourne's CH2 Building

Directory of Open Access Journals (Sweden)

Lu Aye

2012-11-01

Full Text Available The understanding of ventilation requirements in commercial buildings has been significantly revised in the last 10-15 years. A link between health, productivity and increased fresh air use has been established by some research and this understanding underpins the ventilation philosophy adopted for the CH2 building. The ventilation system design for CH2 that has been evaluated in this paper envisages a mechanically driven system during the day, using the displacement technique to distribute filtered air. All introduced air will be drawn from outside and no recycling of air will occur. Natural ventilation will be employed at night using the stack effect, enhanced by turbine ventilators. This paper critiques the proposed ventilation system in the light of international experience and the particular conditions of the building's location. The evidence suggests that natural ventilation sometimes may be inadequate to achieve the desired objectives. Minimization of indoor pollutants, adequate filtration and high levels of ventilation should, however, ensure satisfactory air quality during occupied hours.

New opportunities for ventilation assistance in buildings under Saharan climatic conditions

Directory of Open Access Journals (Sweden)

Kaoulal Rabea

2017-01-01

Full Text Available The aim of this paper is devoted to the coupling of ventilation systems with buildings with low energy performances under a specific Saharan climate. In the second part, the objective is to diagnose and quantify energy consumptions due to the ventilation of a real residential building in Ghardaia site. As result, ventilation system can bring a positive support to the thermos-aeraulic comfort by controlling the mass flow rate of the air entering to the heated or/and cooled building zone. Heat losses due to the ventilation system represent 4.75% of the total losses; the provided heat exchange in this case requires an additional consumption of around 6.6058% of the total energy needs.

Ventilation in school buildings. Special issue; Ventilatie in schoolgebouwen. Themanummer

Energy Technology Data Exchange (ETDEWEB)

Zeiler, W.; Boxem, G.; Van Bruchem, M.; Smits, E.H.J.; Van Dijken, F. [Technische Universiteit Eindhoven, Eindhoven (Netherlands); Joosten, L.; Clocquet, R. [DHV Bouw en Industrie, Amersfoort (Netherlands); Pernot, C. [TNO Bouw, Delft (Netherlands); Haans, L.; Boerstra, A.C. [BBA Boerstra Binnenmilieu Advies, Rotterdam (Netherlands); Leenaerts, C.L.M.; Donze, G.J. [W/E adviseurs duurzaam bouwen, Gouda (Netherlands); Leysen, L.M. [Astma Fonds, Leusden (Netherlands); Blezer, I.H.W. [Hollman Adviseurs, Venlo (Netherlands); Meester, A.W.J. [Alusta, Natuurlijke Ventilatietechniek, Etten Leur (Netherlands); Bronsema, B. [Faculteit der Bouwkunde, Bronsema Consult, Technische Universiteit Delft, Delft (Netherlands)

2005-10-01

In this special issue one editorial and 9 articles are dedicated to several aspects with regard to ventilation in school buildings: (1) healthy and draught-free ventilation in schools; (2) air quality and comfort in primary schools; (3) preparatory study on the indoor environment in primary schools; (4) options to improve ventilation in school buildings; (5) the relation between the indoor environment in classrooms and the health of students; (6) the activities of the Asthma Fund to create healthy school buildings for children suffering asthma; (7) the necessity of mechanical ventilation in school buildings; (8) demand-controlled ventilation in schools; (9) first experiences with a newly built primary school. [Dutch] In deze speciale aflevering zijn 1 redactioneel artikel en 9 artikelen gewijd aan verschillende aspecten m.b.t. ventilatie in schoolgebouwen: (1) onderzoek naar gezond en tochtvrij ventileren; (2) luchtkwaliteit en comfort op basisscholen: (3) voorstudie binnenmilieu basisscholen; (4) opties om de ventilatie in scholen te verbeteren; (5) de relatie tussen het binnenmilieu in klaslokalen en de gezondheid van studenten; (6) activiteiten van het Astma Fonds voor gezonde schoolgebouwen voor kinderen met astma; (7) de noodzaak voor mechanische ventilatie in schoolgebouwen; (8) vraaggestuurde ventilatie in scholen; (9) de eerste ervaringen in een nieuwe basisschool in Voorschoten.

Ventilation, temperature, and HVAC characteristics in small and medium commercial buildings in California.

Science.gov (United States)

Bennett, D H; Fisk, W; Apte, M G; Wu, X; Trout, A; Faulkner, D; Sullivan, D

2012-08-01

This field study of 37 small and medium commercial buildings throughout California obtained information on ventilation rate, temperature, and heating, ventilating, and air-conditioning (HVAC) system characteristics. The study included seven retail establishments; five restaurants; eight offices; two each of gas stations, hair salons, healthcare facilities, grocery stores, dental offices, and fitness centers; and five other buildings. Fourteen (38%) of the buildings either could not or did not provide outdoor air through the HVAC system. The air exchange rate averaged 1.6 (s.d. = 1.7) exchanges per hour and was similar between buildings with and without outdoor air supplied through the HVAC system, indicating that some buildings have significant leakage or ventilation through open windows and doors. Not all buildings had sufficient air exchange to meet ASHRAE 62.1 Standards, including buildings used for fitness centers, hair salons, offices, and retail establishments. The majority of the time, buildings were within the ASHRAE temperature comfort range. Offices were frequently overcooled in the summer. All of the buildings had filters, but over half the buildings had a filter with a minimum efficiency reporting value rating of 4 or lower, which are not very effective for removing fine particles. Most U.S. commercial buildings (96%) are small- to medium-sized, using nearly 18% of the country's energy, and sheltering a large population daily. Little is known about the ventilation systems in these buildings. This study found a wide variety of ventilation conditions, with many buildings failing to meet relevant ventilation standards. Regulators may want to consider implementing more complete building inspections at commissioning and point of sale. © 2012 John Wiley & Sons A/S.

Passive Cooling of buildings by night-time ventilation

DEFF Research Database (Denmark)

Artmann, Nikolai; Manz, Heinrich; Heiselberg, Per

coefficients below about 4 W/m2K. Heat transfer during night-time ventilation in case of mixing and displacement ventilation was investigated in a full scale test room at Aalborg University. In the experiments the temperature efficiency of the ventilation was determined. Based on the previous re-sults a method...... are still hesitant to apply passive cooling techniques. As night-time ventilation is highly dependent on climatic conditions, a method for quantifying the climatic cooling potential was developed and the impact of climate warming was investigated. Although a clear decrease was found, significant potential...... will remain, especially if night-time ventilation is applied in combination with other cooling methods. Building energy simulations showed that the performance of night-time ventilation is also affected by the heat transfer at internal room surfaces, as the cooling effect is very limited for heat transfer...

New Air Cleaning Strategies for Reduced Commercial Building Ventilation Energy

Energy Technology Data Exchange (ETDEWEB)

Sidheswaran, Meera; Destaillats, Hugo; Sullivan, Douglas P.; Fisk, William J.

2010-10-27

Approximately ten percent of the energy consumed in U.S. commercial buildings is used by HVAC systems to condition outdoor ventilation air. Reducing ventilation rates would be a simple and broadly-applicable energy retrofit option, if practical counter measures were available that maintained acceptable concentrations of indoor-generated air pollutants. The two general categories of countermeasures are: 1) indoor pollutant source control, and 2) air cleaning. Although pollutant source control should be used to the degree possible, source control is complicated by the large number and changing nature of indoor pollutant sources. Particle air cleaning is already routinely applied in commercial buildings. Previous calculations indicate that particle filtration consumes only 10percent to 25percent of the energy that would otherwise be required to achieve an equivalent amount of particle removal with ventilation. If cost-effective air cleaning technologies for volatile organic compounds (VOCs) were also available, outdoor air ventilation rates could be reduced substantially and broadly in the commercial building stock to save energy. The research carried out in this project focuses on developing novel VOC air cleaning technologies needed to enable energy-saving reductions in ventilation rates. The minimum required VOC removal efficiency to counteract a 50percent reduction in ventilation rate for air cleaning systems installed in the HVAC supply airstream is modest (generally 20percent or less).

Reduced energy use for ventilation of buildings through selection of low-polluting building materials and furniture. Final Report; Reduceret energiforbrug til ventilation af bygninger hvori der systematisk er valgt lav-forurenende materialer og inventar. Slutrapport

Energy Technology Data Exchange (ETDEWEB)

2007-11-15

The main objective of the research project was to study the potential of reducing energy used for ventilating buildings by using low-polluting building materials and thereby ensuring that indoor air quality will not be compromised. To quantify this potential, the exposure-response relationships, i.e. the relationships between ventilation rate and the perceived indoor air quality (indoor air quality perceived by humans as opposed to indoor air quality evaluated by chemical measurements), were established for rooms furnished with different more or less polluting materials. Based on these results simulations of energy used for ventilation were carried out for selected building scenarios. The exposure-response relationships were established by summarizing existing data reported in the literature and by a series of new experiments. The data summarized by reviewing the literature included data for building materials and furnishing tested in a laboratory setting in small-scale ventilated glass chambers, and in full-scale in ventilated climate chambers, test rooms or normal offices. Relevant low-polluting building materials were selected based on the literature review and a series of new experiments performed in ventilated small-scale glass chambers. Then the final experiments in which the effects of using low-polluting materials on perceived air quality were carried out in ventilated small-scale glass chambers and in full-scale test rooms ventilated with different outdoor air supply rates. Simulations of energy used for ventilation were carried out using BSim software. During simulations the ventilation rate was varied to obtain different levels of air quality when low-polluting building materials had been used, and it was examined how these changes influence the energy use. The results show that the exposure-response relationships vary between different building materials and thus the ventilation requirement to achieve a certain level of perceived indoor air quality vary

Passive cooling of buildings by night-time ventilation - Final report

Energy Technology Data Exchange (ETDEWEB)

Artmann, N.; Manz, H. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Duebendorf (Switzerland); Heiselberg, P. [Aalborg University, Aalborg (Denmark)

2008-07-01

Due to an overall trend towards an increasing cooling energy demand in buildings in many European countries over the last few decades, passive cooling by night-time ventilation is seen as a promising concept. However, because of uncertainties in thermal comfort predictions, architects and engineers are still hesitant to apply passive cooling techniques. As night-time ventilation is highly dependent on climatic conditions, a method for quantifying the climatic cooling potential was developed and the impact of climate warming was investigated. Although a clear temperature decrease was found, significant potential will remain, especially if night-time ventilation is applied in combination with other cooling methods. Building energy simulations showed that the performance of night-time ventilation is also affected by the heat transfer at internal room surfaces, as the cooling effect is very limited due to heat transfer coefficients below about 4 W/m{sup 2}K. Heat transfer during night-time ventilation in case of mixing and displacement ventilation was investigated in a full scale test room at Aalborg University. In the experiments the temperature efficiency of the ventilation was determined. Based on the previous results a method for estimating the potential for cooling by night-time ventilation at an early stage of design was developed. (author)

Parameter study on performance of building cooling by night-time ventilation

DEFF Research Database (Denmark)

Artmann, Nikolai; Manz, H.; Heiselberg, Per

2008-01-01

of different parameters such as building construction, heat gains, air change rates, heat transfer coefficients and climatic conditions including annual variations on the number of overheating degree hours (operative room temperature >26 °C) was evaluated. Climatic conditions and air flow rate during night......Especially for commercial buildings in moderate climates, night-time ventilation seems to be a simple and energy-efficient approach to improve thermal comfort in summer. However, due to uncertainties in the prediction of thermal comfort in buildings with night-time ventilation, architects...... and engineers are still hesitant to apply this technique. In order to reduce the uncertainties, the most important parameters affecting night ventilation performance need to be identified. A typical office room was therefore modelled using a building energy simulation programme (HELIOS), and the effect...

Supply Ventilation and Prevention of Carbon Monoxide (II) Ingress into Building Premises

Science.gov (United States)

Litvinova, N. A.

2017-11-01

The article contains the relationships of carbon monoxide (II) concentration versus height-above-ground near buildings derived based on results of studies. The results of studies are crucial in preventing external pollutants ingress into a ventilation system. Being generated by external emission sources, such as motor vehicles and city heating plants, carbon monoxide (II) enters the premises during operation of a supply ventilation system. Fresh air nomographic charts were drawn to select the height of a fresh air intake into the ventilation system. Nomographic charts take into account external sources. The selected emission sources are located at various levels above ground relative to the building. The recommendations allow designing supply ventilation taking into account the quality of ambient air through the whole building height.

The effect of using low-polluting building materials on ventilation requirements and energy use in buildings

Energy Technology Data Exchange (ETDEWEB)

Wargocki, P.; Frontczak, M. (International Centre for Indoor Environment and Energy, Dept. of Mechanical Engineering, DTU, Kgs. Lyngby (DK)); Knudsen, Henrik N. (Danish Building Research Institute, Aalborg Univ., Hoersholm (DK))

2007-07-01

The main objective of the ongoing research project described in this paper was to study the potential for reducing energy used for ventilating buildings by using low-polluting building materials, without compromising the indoor air quality. To quantify this potential, the exposure-response relationships, i.e. the relationships between ventilation rate and perceived indoor air quality, were established for rooms furnished with different categories of polluting materials and the simulations of energy used for ventilation were carried out. The exposure-response relationships were based on a summary of data reported in the literature on exposure-response relationships for materials tested in laboratory settings in small-scale glass chambers, and in full-scale in climate chambers, test rooms or normal offices. New experiments were also considered in which the effect of using low-polluting materials on perceived air quality was examined in test rooms ventilated with different outdoor air supply rates, low-polluting materials being selected in small glass chambers. The results suggest that the exposure-response relationships vary between different building materials and that the perceived air quality can be improved considerably when polluting building materials are substituted with materials that pollute less. The preliminary energy simulations indicate that selecting low-polluting materials will result in considerable energy savings as a result of reducing the ventilation rates required to achieve acceptable indoor air quality. (au)

Energy and cost associated with ventilating office buildings in a tropical climate.

Science.gov (United States)

Rim, Donghyun; Schiavon, Stefano; Nazaroff, William W

2015-01-01

Providing sufficient amounts of outdoor air to occupants is a critical building function for supporting occupant health, well-being and productivity. In tropical climates, high ventilation rates require substantial amounts of energy to cool and dehumidify supply air. This study evaluates the energy consumption and associated cost for thermally conditioning outdoor air provided for building ventilation in tropical climates, considering Singapore as an example locale. We investigated the influence on energy consumption and cost of the following factors: outdoor air temperature and humidity, ventilation rate (L/s per person), indoor air temperature and humidity, air conditioning system coefficient of performance (COP), and cost of electricity. Results show that dehumidification of outdoor air accounts for more than 80% of the energy needed for building ventilation in Singapore's tropical climate. Improved system performance and/or a small increase in the indoor temperature set point would permit relatively large ventilation rates (such as 25 L/s per person) at modest or no cost increment. Overall, even in a thermally demanding tropical climate, the energy cost associated with increasing ventilation rate up to 25 L/s per person is less than 1% of the wages of an office worker in an advanced economy like Singapore's. This result implies that the benefits of increasing outdoor air ventilation rate up to 25 L/s per person--which is suggested to provide for productivity increases, lower sick building syndrome symptom prevalence, and reduced sick leave--can be much larger than the incremental cost of ventilation.

Cost-benefit analysis of decreased ventilation rates and radon exhalation from building materials

International Nuclear Information System (INIS)

Ericson, S.O.

1984-01-01

Decreased ventilation, achieved by weather stripping and other tightening measures, is the most cost effective way to energy conservation. A very low investment can result in a considerable decrease in ventilation rate. For a typical detached house in Sweden this can be equivalent to a decrease in oil consumption of 0.5 m 3 . At present price this corresponds to a saving of SEK 1200, 150 US dollars per annum. The contribution of the building materials to the concentration of radon in indoor air is approximately the inverse to air exchange rate. For a small change in ventilation rate and cost, in SEK/man Sv or US dollar/man Sv, is a function of ventilation rate, exhalation from building materials, the ratio between surface of walls, floor and ceiling to the volume of air. Thus, it is possible to find the specific ventilation rate where the marginal cost for a small increase in ventilation rate and the marginal reduction in radon concentration will give a specific amount of money for each man Sv. Examples are given. Conclusions are that for most building materials in a climate like the Swedish, there are other factors than exhalation of radon from building materials that sets the lower limit of recommendable ventilation rate. (Author)

Rising damp in building walls: the wall base ventilation system

Energy Technology Data Exchange (ETDEWEB)

Guimaraes, A.S.; Delgado, J.M.P.Q.; Freitas, V.P. de [Faculdade de Engenharia da Universidade do Porto, Laboratorio de Fisica das Construcoes (LFC), Departamento de Engenharia Civil, Porto (Portugal)

2012-12-15

This work intends to validate a new system for treating rising damp in historic buildings walls. The results of laboratory experiments show that an efficient way of treating rising damp is by ventilating the wall base, using the HUMIVENT technique. The analytical model presented describes very well the observed features of rising damp in walls, verified by laboratory tests, who contributed for a simple sizing of the wall base ventilation system that will be implemented in historic buildings. (orig.)

Evaluation of Ventilation Strategies in New Construction Multifamily Buildings

Energy Technology Data Exchange (ETDEWEB)

Maxwell, S. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Berger, D. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States); Zuluaga, M. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

2014-07-01

In multifamily buildings, particularly in the Northeast, exhaust ventilation strategies are the norm as a means of meeting both local exhaust and whole-unit mechanical ventilation rates. The issue of where the "fresh" air is coming from is gaining significance as air-tightness standards for enclosures become more stringent. CARB researchers have found that most new high performance, multifamily housing in the Northeast use one of four strategies for ventilation: continuous exhaust only with no designated supply or make-up air source, continuous exhaust with ducted make-up air to apartments, continuous exhaust with supply through a make-up air device integral to the unit HVAC, and continuous exhaust with supply through a passive inlet device, such as a trickle vent. Insufficient information is available to designers on how these various systems are best applied. Product performance data are based on laboratory tests, but there is no guarantee that those conditions will exist consistently in the finished building. In this research project, CARB evaluated the four ventilation strategies in the field to validate system performance.

Thermal Comfort and Ventilation Criteria for low Energy Residential Buildings in Building Codes

DEFF Research Database (Denmark)

Cao, Guangyu; Kurnitski, Jarek; Awbi, Hazim

2012-01-01

of the indoor air quality in such buildings. Currently, there are no global guidelines for specifying the indoor thermal environment in such low-energy buildings. The objective of this paper is to analyse the classification of indoor thermal comfort levels and recommended ventilation rates for different low...

Natural ventilation systems to enhance sustainability in buildings: a review towards zero energy buildings in schools

Science.gov (United States)

Gil-Baez, Maite; Barrios-Padura, Ángela; Molina-Huelva, Marta; Chacartegui, Ricardo

2017-11-01

European regulations set the condition of Zero Energy Buildings for new buildings since 2020, with an intermediate milestone in 2018 for public buildings, in order to control greenhouse gases emissions control and climate change mitigation. Given that main fraction of energy consumption in buildings operation is due to HVAC systems, advances in its design and operation conditions are required. One key element for energy demand control is passive design of buildings. On this purpose, different recent studies and publications analyse natural ventilation systems potential to provide indoor air quality and comfort conditions minimizing electric power consumption. In these passive systems are of special relevance their capacities as passive cooling systems as well as air renovation systems, especially in high-density occupied spaces. With adequate designs, in warm/mild climates natural ventilation systems can be used along the whole year, maintaining indoor air quality and comfort conditions with small support of other heating/cooling systems. In this paper is analysed the state of the art of natural ventilation systems applied to high density occupied spaces with special focus on school buildings. The paper shows the potential and applicability of these systems for energy savings and discusses main criteria for their adequate integration in school building designs.

Evaluation of Ventilation Strategies in New Construction Multifamily Buildings

Energy Technology Data Exchange (ETDEWEB)

Maxwell, S.; Berger, D.; Zuluaga, M.

2014-07-01

In multifamily buildings, particularly in the Northeast, exhaust ventilation strategies are the norm as a means of meeting both local exhaust and whole-unit mechanical ventilation rates. The issue of where the 'fresh' air is coming from is gaining significance as air-tightness standards for enclosures become more stringent, and the 'normal leakage paths through the building envelope' disappear. CARB researchers have found that the majority of high performance, new construction, multifamily housing in the Northeast use one of four general strategies for ventilation: continuous exhaust only with no designated supply or make-up air source, continuous exhaust with ducted make-up air to apartments, continuous exhaust with supply through a make-up air device integral to the unit HVAC, and continuous exhaust with supply through a passive inlet device, such as a trickle vent. Insufficient information is available to designers on how these various systems are best applied. Product performance data are based on laboratory tests, and the assumption is that products will perform similarly in the field. Proper application involves matching expected performance at expected building pressures, but there is no guarantee that those conditions will exist consistently in the finished building. This research effort, which included several weeks of building pressure monitoring, sought to provide field validation of system performance. The performance of four substantially different strategies for providing make-up air to apartments was evaluated.

Ventilation

DEFF Research Database (Denmark)

Nielsen, Toke Rammer; Svendsen, Sv Aa Højgaard

1999-01-01

The note concerns ventilation in residential buildings. Describes components in ventilation systems, electric energy consumption and different ventilation systems with heat exchanger.......The note concerns ventilation in residential buildings. Describes components in ventilation systems, electric energy consumption and different ventilation systems with heat exchanger....

Climatic potential for passive cooling of buildings by night-time ventilation in Europe

International Nuclear Information System (INIS)

Artmann, N.; Manz, H.; Heiselberg, P.

2007-01-01

Due to an overall trend towards less heating and more cooling demands in buildings in many European countries over the last few decades, passive cooling by night-time ventilation is seen as a promising technique, particularly for commercial buildings in the moderate or cold climates of Central, Eastern and Northern Europe. The basic concept involves cooling the building structure overnight in order to provide a heat sink that is available during the occupancy period. In this study, the potential for passive cooling of buildings by night-time ventilation was evaluated by analysing climatic data, without considering any building-specific parameters. An approach for calculating degree-hours based on a variable building temperature - within a standardized range of thermal comfort - is presented and applied to climatic data of 259 stations all over Europe. The results show a high potential for night-time ventilative cooling over the whole of Northern Europe and still significant potential in Central, Eastern and even some regions of Southern Europe. However, due to the inherent stochastic properties of weather patterns, a series of warmer nights can occur at some locations, where passive cooling by night-time ventilation alone might not be sufficient to guarantee thermal comfort

Effects of types of ventilation system on indoor particle concentrations in residential buildings.

Science.gov (United States)

Park, J S; Jee, N-Y; Jeong, J-W

2014-12-01

The objective of this study was to quantify the influence of ventilation systems on indoor particle concentrations in residential buildings. Fifteen occupied, single-family apartments were selected from three sites. The three sites have three different ventilation systems: unbalanced mechanical ventilation, balanced mechanical ventilation, and natural ventilation. Field measurements were conducted between April and June 2012, when outdoor air temperatures were comfortable. Number concentrations of particles, PM2.5 and CO2 , were continuously measured both outdoors and indoors. In the apartments with natural ventilation, I/O ratios of particle number concentrations ranged from 0.56 to 0.72 for submicron particles, and from 0.25 to 0.60 for particles larger than 1.0 μm. The daily average indoor particle concentration decreased to 50% below the outdoor level for submicron particles and 25% below the outdoor level for fine particles, when the apartments were mechanically ventilated. The two mechanical ventilation systems reduced the I/O ratios by 26% for submicron particles and 65% for fine particles compared with the natural ventilation. These results showed that mechanical ventilation can reduce exposure to outdoor particles in residential buildings. Results of this study confirm that mechanical ventilation with filtration can significantly reduce indoor particle levels compared with natural ventilation. The I/O ratios of particles substantially varied at the naturally ventilated apartments because of the influence of variable window opening conditions and unsteadiness of wind flow on the penetration of outdoor air particles. For better prediction of the exposure to outdoor particles in naturally ventilated residential buildings, it is important to understand the penetration of outdoor particles with variable window opening conditions. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Passive Design Strategies to Enhance Natural Ventilation in Buildings "Election of Passive Design Strategies to Achieve Natural Ventilation in Iraqi Urban Environment with Hot Arid Climate"

Directory of Open Access Journals (Sweden)

Ghada M.Ismael Abdul Razzaq Kamoona

2016-06-01

Full Text Available the natural ventilation in buildings is one of effective strategies for achieving energy efficiency in buildings by employing methods and ways of passive design, as well as its efficiency in providing high ranges of thermal comfort for occupants in buildings and raises their productivity. Because the concept of natural ventilation for many people confined to achieve through the windows and openings only, become necessary to provide this research to demonstrate the various passive design strategies for natural ventilation. Then, research problem: Insufficient knowledge about the importance and mechanism of the application of passive design strategies for natural ventilation in buildings. The research objective is: Analysis of passive design strategies to achieve natural ventilation in buildings, for the purpose of the proper selection of them to Iraqi urban environment. Accordingly, the research included two parts: First, the theoretical part, which dealt with the conceptual framework of natural ventilation and deriving the most important aspects in it, in order to adopted as a base for the practical part of the research. Second: the practical part, which analyzed examples of buildings projects that employed various design strategies for natural ventilation, according to the theoretical framework that has been drawn. The main conclusion is, Necessity to adopt various passive design strategies for natural ventilation in Iraqi urban environment with hot dry climate, as they have a significant impact in reducing the energy consumption for the purposes of ventilation and cooling, as well as for its efficiency in improving air quality in indoor environments of buildings.

Appropriate Ventilation Solutions for the Iconographic Buildings from the Fifties

DEFF Research Database (Denmark)

Vestergaard, Inge; Blyt, Henrik

2016-01-01

will show a development to the introduction of mechanical ventilation in the building stock with a particular focus on decentralized ventilation systems. To evaluate the retrofitting initiatives a cross-disciplinary corporation between the professions of architecture and engineering are required....... The paper concludes that interdisciplinary ways of working will improve both architecture and preservation and comfort, and that higher value hereby is created. Furthermore the new initiatives from the industry are shown, which indicates a movement towards innovation of decentralized ventilation solutions....

Computational Analysis of Natural Ventilation Flows in Geodesic Dome Building in Hot Climates

Directory of Open Access Journals (Sweden)

Zohreh Soleimani

2016-08-01

Full Text Available For centuries, dome roofs were used in traditional houses in hot regions such as the Middle East and Mediterranean basin due to its thermal advantages, structural benefits and availability of construction materials. This article presents the computational modelling of the wind- and buoyancy-induced ventilation in a geodesic dome building in a hot climate. The airflow and temperature distributions and ventilation flow rates were predicted using Computational Fluid Dynamics (CFD. The three-dimensional Reynolds-Averaged Navier-Stokes (RANS equations were solved using the CFD tool ANSYS FLUENT15. The standard k-epsilon was used as turbulence model. The modelling was verified using grid sensitivity and flux balance analysis. In order to validate the modelling method used in the current study, additional simulation of a similar domed-roof building was conducted for comparison. For wind-induced ventilation, the dome building was modelled with upper roof vents. For buoyancy-induced ventilation, the geometry was modelled with roof vents and also with two windows open in the lower level. The results showed that using the upper roof openings as a natural ventilation strategy during winter periods is advantageous and could reduce the indoor temperature and also introduce fresh air. The results also revealed that natural ventilation using roof vents cannot satisfy thermal requirements during hot summer periods and complementary cooling solutions should be considered. The analysis showed that buoyancy-induced ventilation model can still generate air movement inside the building during periods with no or very low wind.

Thermal Comfort in a Naturally-Ventilated Educational Building

Directory of Open Access Journals (Sweden)

David Mwale Ogoli

2012-11-01

Full Text Available A comprehensive study of thermal comfort in a naturally ventilated education building (88,000 ft2 in a Chicago suburb will be conducted with 120 student subjects in 2007. This paper discusses some recent trends in worldwide thermal comfort studies and presents a proposal of research for this building through a series of questionnaire tables. Two research methods used inthermal comfort studies are field studies and laboratory experiments in climate-chambers. The various elements that constitute a “comfortable” thermal environment include physical factors (ambient air temperature, mean radiant temperature, air movement and humidity, personal factors(activity and clothing, classifications (gender, age, education, etc. and psychological expectations (knowledge, experience, psychological effect of visual warmth by, say, a fireplace. Comparisons are made using data gathered from Nairobi, Kenya.Keywords: Comfort, temperature, humidity and ventilation

Assessment of Natural Ventilation Potential for Residential Buildings across Different Climate Zones in Australia

Directory of Open Access Journals (Sweden)

Zijing Tan

2017-09-01

Full Text Available In this study, the natural ventilation potential of residential buildings was numerically investigated based on a typical single-story house in the three most populous climate zones in Australia. Simulations using the commercial simulation software TRNSYS (Transient System Simulation Tool were performed for all seasons in three representative cities, i.e., Darwin for the hot humid summer and warm winter zone, Sydney for the mild temperate zone, and Melbourne for the cool temperate zone. A natural ventilation control strategy was generated by the rule-based decision-tree method based on the local climates. Natural ventilation hour (NVH and satisfied natural ventilation hour (SNVH were employed to evaluate the potential of natural ventilation in each city considering local climate and local indoor thermal comfort requirements, respectively. The numerical results revealed that natural ventilation potential was related to the local climate. The greatest natural ventilation potential for the case study building was observed in Darwin with an annual 4141 SNVH out of 4728 NVH, while the least natural ventilation potential was found in the Melbourne case. Moreover, summer and transition seasons (spring and autumn were found to be the optimal periods to sustain indoor thermal comfort by utilising natural ventilation in Sydney and Melbourne. By contrast, natural ventilation was found applicable over the whole year in Darwin. In addition, the indoor operative temperature results demonstrated that indoor thermal comfort can be maintained only by utilising natural ventilation for all cases during the whole year, except for the non-natural ventilation periods in summer in Darwin and winter in Melbourne. These findings could improve the understanding of natural ventilation potential in different climates, and are beneficial for the climate-conscious design of residential buildings in Australia.

Improving energy performance of school buildings while ensuring indoor air quality ventilation

Energy Technology Data Exchange (ETDEWEB)

Becker, Rachel; Goldberger, Itamar [Technion - Israel Institute of Technology, Haifa (Israel). Faculty of Civil and Environmental Engineering, Department of Structural Engineering and Construction Management; Paciuk, Monica [National Building Research Institute, Technion, Haifa (Israel)

2007-09-15

Energy conscious design of school buildings, as well as deemed-to-satisfy provisions in a Performance Based Energy Code, should address the problem known as the energy efficiency - thermal comfort - indoor air quality dilemma (EE-TC-IAQ Dilemma). In warm and moderate climates, the large internal heat sources usually found in school buildings prevent achieving thermal comfort without active cooling in summer, but are not sufficient to eliminate the need for heating in winter. Commonly used air-conditioners do not improve air quality, while natural ventilation induces uncontrolled energy losses. In this study, a step by step process was used for the development of deemed-to-satisfy design solutions, which cope with the EE-TC-IAQ Dilemma, for a performance based code. A distinction is made between improving building design variables and improving ventilation schemes. Results indicate that implementation of improved ventilation schemes in an otherwise well designed energy-conscious building result in savings of 28-30% and 17-18% for northern and southern classroom orientations, respectively. (author)

Thermal Comfort in a Naturally-Ventilated Educational Building

OpenAIRE

David Mwale Ogoli

2012-01-01

A comprehensive study of thermal comfort in a naturally ventilated education building (88,000 ft2) in a Chicago suburb will be conducted with 120 student subjects in 2007. This paper discusses some recent trends in worldwide thermal comfort studies and presents a proposal of research for this building through a series of questionnaire tables. Two research methods used inthermal comfort studies are field studies and laboratory experiments in climate-chambers. The various elements that constitu...

Change-over natural and mechanical ventilation system energy consumption in single-family buildings

Science.gov (United States)

Kostka, Maria; Szulgowska-Zgrzywa, Małgorzata

2017-11-01

The parameters of the outside air in Poland cause that in winter it is reasonable to use a mechanical ventilation equipped with a heat recovery exchanger. The time of spring, autumn, summer evenings and nights are often characterized by the parameters of the air, which allow for a natural ventilation and reduce the electricity consumption. The article presents the possibilities of energy consumption reduction for three energy standards of buildings located in Poland, ventilated by a change-over hybrid system. The analysis was prepared on the assumption that the air-to-water heat pump is the heat source for the buildings.

Using Coupled Energy, Airflow and IAQ Software (TRNSYS/CONTAM) to Evaluate Building Ventilation Strategies.

Science.gov (United States)

Dols, W Stuart; Emmerich, Steven J; Polidoro, Brian J

2016-03-01

Building energy analysis tools are available in many forms that provide the ability to address a broad spectrum of energy-related issues in various combinations. Often these tools operate in isolation from one another, making it difficult to evaluate the interactions between related phenomena and interacting systems, forcing oversimplified assumptions to be made about various phenomena that could otherwise be addressed directly with another tool. One example of such interdependence is the interaction between heat transfer, inter-zone airflow and indoor contaminant transport. In order to better address these interdependencies, the National Institute of Standards and Technology (NIST) has developed an updated version of the multi-zone airflow and contaminant transport modelling tool, CONTAM, along with a set of utilities to enable coupling of the full CONTAM model with the TRNSYS simulation tool in a more seamless manner and with additional capabilities that were previously not available. This paper provides an overview of these new capabilities and applies them to simulating a medium-size office building. These simulations address the interaction between whole-building energy, airflow and contaminant transport in evaluating various ventilation strategies including natural and demand-controlled ventilation. CONTAM has been in practical use for many years allowing building designers, as well as IAQ and ventilation system analysts, to simulate the complex interactions between building physical layout and HVAC system configuration in determining building airflow and contaminant transport. It has been widely used to design and analyse smoke management systems and evaluate building performance in response to chemical, biological and radiological events. While CONTAM has been used to address design and performance of buildings implementing energy conserving ventilation systems, e.g., natural and hybrid, this new coupled simulation capability will enable users to apply the

Numerical investigations of buoyancy-driven natural ventilation in a simple three-storey atrium building and thermal comfort evaluation

International Nuclear Information System (INIS)

Hussain, Shafqat; Oosthuizen, Patrick H.

2013-01-01

The numerical investigations of buoyancy-driven natural ventilation and thermal comfort evaluation in a simple three-storey atrium building as a part of the passive ventilation strategy was undertaken using a validated Computational Fluid Dynamic (CFD) model. The Reynolds Averaged Navier–Stokes (RANS) modeling approach with the SST-k–ω turbulence model and the discrete transfer radiation model (DTRM) was used for the numerical investigations. The steady-state governing equations were solved using a commercial solver FLUENT©. Various flow situations of the buoyancy-driven natural ventilation in the building during day and night time were examined. The numerical results obtained for the airflow rates, airflow patterns and temperature distributions inside the building are presented in this paper. Using the numerical results, the well-known thermal comfort indices PMV (predicted mean vote) and PPD (predicted percentage of dissatisfied) were calculated for the evaluation of the thermal comfort conditions in the occupied regions of the building. It was noticed that thermal conditions prevailing in the occupied areas of the building as a result of using the buoyancy-driven ventilation were mostly in comfort zone. From the study of the night time ventilation, it was found that hot water (80 °C) circulation (heated by solar collectors during daytime) along the chimney walls during night time and heat sources present in the building can be useful in inducing night ventilation airflows in the building as a part of the passive ventilation strategy. -- Highlights: • A simple three-storey atrium building. • Numerical modeling of buoyancy-driven ventilation flow in the building. • Effect of solar intensity and geographical location on ventilation. • CFD predictions were used to calculate thermal comfort indices. • Evaluation of thermal comfort conditions for the occupants

The renewal of the ventilation test for residential buildings in the Netherlands; Woonbond vernieuwt toets ventilatie

Energy Technology Data Exchange (ETDEWEB)

Koevoet, H. (ed.)

2003-05-01

It appears that many residential buildings in the Netherlands do not meet ventilation regulations as formulated in the Building Decree of 1992. The renewed checklist Ventilation is a tool by means of which the quality of the ventilation in residential buildings can be tested. [Dutch] De ventilatie schiet in onrustbarend veel woningen tekort. Het is echter niet altijd eenvoudig orn vast te stellen of de ventilatie onvoldoende is. De vernieuwde Toetstijst Ventilatie van de Woonbond, VEH en het Astma Fonds geeft een goede indicatie.

An Overview of Residential Ventilation Activities in the Building America Program (Phase I)

Energy Technology Data Exchange (ETDEWEB)

Barley, D.

2001-05-21

This report provides an overview of issues involved in residential ventilation; provides an overview of the various ventilation strategies being evaluated by the five teams, or consortia, currently involved in the Building America Program; and identifies unresolved technical issues.

An overview of the TA-55, Building PF-4 ventilation system

International Nuclear Information System (INIS)

1994-01-01

An overview of the TA-55, Building PF-4 ventilation system is provided in the following sections. Included are descriptions of the zone configurations, equipment-performance criteria, ventilation support systems, and the ventilation-system evaluation criteria. Section 4.2.1.1 provides a brief discussion of the ventilation system function. Section 4.2.1.2 provides details on the overall system configuration. Details of system interfaces and support systems are provided in Section 4.2.1.3. Section 4.2.1.4 describes instrumentation and control needed to operate the ventilation system. Finally, Sections 4.2.1.5 and 4.2.1.6 describe system surveillance/maintenance and Technical Safety Requirements (TSR) Limitations, respectively. Note that the numerical parameters included in this description are considered nominal; set points and other specifications actually fall within operational bands

An overview of the TA-55, Building PF-4 ventilation system

Energy Technology Data Exchange (ETDEWEB)

NONE

1994-02-22

An overview of the TA-55, Building PF-4 ventilation system is provided in the following sections. Included are descriptions of the zone configurations, equipment-performance criteria, ventilation support systems, and the ventilation-system evaluation criteria. Section 4.2.1.1 provides a brief discussion of the ventilation system function. Section 4.2.1.2 provides details on the overall system configuration. Details of system interfaces and support systems are provided in Section 4.2.1.3. Section 4.2.1.4 describes instrumentation and control needed to operate the ventilation system. Finally, Sections 4.2.1.5 and 4.2.1.6 describe system surveillance/maintenance and Technical Safety Requirements (TSR) Limitations, respectively. Note that the numerical parameters included in this description are considered nominal; set points and other specifications actually fall within operational bands.

Demand Controlled Ventilation and Classroom Ventilation

Energy Technology Data Exchange (ETDEWEB)

Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davies, Molly [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eliseeva, Ekaterina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hong, Tienzen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2012-05-01

This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.

Demand controlled ventilation and classroom ventilation

Energy Technology Data Exchange (ETDEWEB)

Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Davies, Molly [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Eliseeva, Ekaterina [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Faulkner, David [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hong, Tienzen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2014-01-06

This document summarizes a research effort on demand controlled ventilation and classroom ventilation. The research on demand controlled ventilation included field studies and building energy modeling.

209-E Building -- Response to ventilation failure evaluation

International Nuclear Information System (INIS)

Foust, D.J.

1998-01-01

This document provides an evaluation and recommendations for radiological workplace air monitoring and response to ventilation failure for the Critical Mass Laboratory, 209-E Building. The Critical Mass Laboratory, part of the 209-E Building, was designed to provide a heavily shielded room where plutonium and uranium liquid solutions could be brought into various critical configurations under readily controlled and monitored conditions. The facility is contained within a one-story L-shaped concrete block and reinforced concrete building. One wing houses offices, a control room, shops, and a common area while the other wing includes an equipment room, the change room, work areas, and the two-story Critical Assembly Room (CAR). Three of the rooms contain radiologically contaminated equipment and materials

Synergic effects of thermal mass and natural ventilation on the thermal behaviour of traditional massive buildings

Science.gov (United States)

Gagliano, A.; Nocera, F.; Patania, F.; Moschella, A.; Detommaso, M.; Evola, G.

2016-05-01

The energy policies about energy efficiency in buildings currently focus on new buildings and on existing buildings in case of energy retrofit. However, historic and heritage buildings, that are the trademark of numerous European cities, should also deserve attention; nevertheless, their energy efficiency is nowadays not deeply investigated. In this context, this study evaluates the thermal performance of a traditional massive building situated in a Mediterranean city. Dynamic numerical simulations were carried out on a yearly basis through the software DesignBuilder, both in free-running conditions and in the presence of an air-conditioning (AC) system. The results highlight that the massive envelope of traditional residential buildings helps in maintaining small fluctuations of the indoor temperature, thus limiting the need for AC in the mid-season and in summer. This feature is highly emphasised by exploiting natural ventilation at night, which allows reducing the building energy demand for cooling by about 30%.The research also indicates that, for Mediterranean climate, the increase in thermal insulation does not always induce positive effects on the thermal performance in summer, and that it might even produce an increase in the heat loads due to the transmission through the envelope.

Methane emission from naturally ventilated livestock buildings can be determined from gas concentration measurements

DEFF Research Database (Denmark)

Bjerg, B; Zhang, Guoqiang; Madsen, J

2012-01-01

Determination of emission of contaminant gases as ammonia, methane, or laughing gas from natural ventilated livestock buildings with large opening is a challenge due to the large variations in gas concentration and air velocity in the openings. The close relation between calculated animal heat pr...... to investigate the influence of feed composition on methane emission in a relative large number of operating cattle buildings and consequently it can support a development towards reduced greenhouse gas emission from cattle production.......Determination of emission of contaminant gases as ammonia, methane, or laughing gas from natural ventilated livestock buildings with large opening is a challenge due to the large variations in gas concentration and air velocity in the openings. The close relation between calculated animal heat...... ventilated, 150 milking cow building. The results showed that the methane emission can be determined with much higher precision than ammonia or laughing gas emissions, and, for methane, relatively precise estimations can be based on measure periods as short as 3 h. This result makes it feasible...

Ventilated buildings optimisation by using a coupled thermal-airflow simulation program

DEFF Research Database (Denmark)

Oropeza-Perez, Ivan; Østergaard, Poul Alberg; Remmen, Arne

2011-01-01

This work shows the optimization of natural ventilation within buildings at the stage of design and behaviour of the occupants. An evaluation is done by coupled multizone air modelling and thermal building simulation by using a deterministic set of input factors comprising among others climate......, local environment, building characteristics, building systems, behaviour of occupants, heat loads. Selected deterministic input factors were varied to generate additional information applied in an optimization loop. With that, it is found that the optimal solution depends to a great deal...

The integration of engineering and architecture: A perspective on natural ventilation for the new San Francisco Federal Building

International Nuclear Information System (INIS)

McConahey, Erin; Haves, Philip; Christ, Tim

2002-01-01

A description of the in-progress design of a new Federal Office Building for San Francisco is used to illustrate a number of issues arising in the design of large, naturally ventilated office buildings. These issues include the need for an integrated approach to design involving the architects, mechanical and structural engineers, lighting designers and specialist simulation modelers. In particular, the use of natural ventilation, and the avoidance of air-conditioning, depends on the high degree of exposed thermal mass made possible by the structural scheme and by the minimization of solar heat gains while maintaining the good daylighting that results from optimization of the facade. Another issue was the need for a radical change in interior space planning in order to enhance the natural ventilation; all the individual enclosed offices are located along the central spine of each floorplate rather than at the perimeter. The role of integration in deterring the undermining of the design through value engineering is discussed. The comfort criteria for the building were established based on the recent extension to the ASHRAE comfort standard based on the adaptive model for naturally ventilated buildings. The building energy simulation program EnergyPlus was used to compare the performance of different natural ventilation strategies. The results indicate that, in the San Francisco climate, wind-driven ventilation provides sufficient nocturnal cooling to maintain comfortable conditions and that external chimneys do not provide significant additional ventilation at times when it when it would be beneficial

Influence of Courtyard Ventilation on Thermal Performance of Office Building in Hot-Humid Climate: A Case Study

Science.gov (United States)

Abbaas, Esra'a. Sh.; Saif, Ala'eddin A.; Munaaim, MAC; Azree Othuman Mydin, Md.

2018-03-01

The influence of courtyard on the thermal performance of Development Department office building in University Malaysia Perlis (UniMAP, Pauh Putra campus) is investigated through simulation study for the effect of ventilation on indoor air temperature and relative humidity of the building. The study is carried out using EnergyPlus simulator interface within OpenStudio and SketchUp plug in software to measure both of air temperature and relative humidity hourly on 21 April 2017 as a design day. The results show that the ventilation through the windows facing the courtyard has sufficient effect on reducing the air temperature compared to the ventilation through external windows since natural ventilation is highly effective on driving the indoor warm air out to courtyard. In addition, the relative humidity is reduced due to ventilation since the courtyard has high ability to remove or dilute indoor airborne pollutants coming from indoor sources. This indicates that the presence of courtyard is highly influential on thermal performance of the building.

Ventilation Relevant Contaminants of Concern in Commercial Buildings Screening Process and Results

Energy Technology Data Exchange (ETDEWEB)

Parthasarathy, Srinandini [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); McKone, Thomas E. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Apte, Michael G. [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States)

2011-04-29

This report summarizes the screening procedure and its results for selecting contaminants of concern (COC), whose concentrations are affected by ventilation in commercial buildings. Many pollutants comprising criteria pollutants, volatile organic compounds (VOCs), semi-volatile organic compounds (SVOCs) and biological contaminants are found in commercial buildings. In this report, we focus primarily on identifying potential volatile organic COC, which are impacted by ventilation. In the future we plan to extend this effort to inorganic gases and particles. Our screening considers compounds detected frequently in indoor air and compares the concentrations to health-guidelines and thresholds. However, given the range of buildings under consideration, the contaminant sources and their concentrations will vary depending on the activity and use of the buildings. We used a literature review to identify a large list of chemicals found in commercial-building indoor air. The VOCs selected were subject to a two stage screening process, and the compounds of greater interest are included in priority List A. Other VOCs that have been detected in commercial buildings are included in priority List B. The compounds in List B, were further classified into groups B1, B2, B3, B4 in order of decreasing interest.

Effect of using low-polluting building materials and increasing ventilation on perceived indoor air quality

Energy Technology Data Exchange (ETDEWEB)

Wargocki, P.; Zuczek, P. (International Centre for Indoor Environment and Energy, Dept. of Mechanical Engineering, DTU, Kgs. Lyngby (DK)); Knudsen, Henrik N. (Danish Building Research Institute, Aalborg Univ., Hoersholm (DK))

2007-07-01

The potential of improving perceived air quality indoors was quantified when low-polluting materials are used and when building ventilation is increased. This was done by studying the relationships between ventilation rate and the perceived indoor air quality. A sensory panel assessed the air quality in test rooms ventilated with realistic outdoor air supply rates, where combinations of high- and low-polluting wall, floor and ceiling materials were set up. These materials were ranked as high- and low-polluting using sensory assessments of air quality in small-scale glass chambers, where they were tested individually. Substituting materials ranked as high-polluting with materials ranked as lower-polluting improved the perceived air quality in the test rooms. This improvement was greater than what was achieved by a realistic increase of the ventilation rate in the test rooms. Thus reducing pollution emitted from building materials that affects the perceived air quality has a considerable potential of limiting the energy for ventilation without compromising indoor air quality. (au)

Experimental and CFD evidence of multiple solutions in a naturally ventilated building.

Science.gov (United States)

Heiselberg, P; Li, Y; Andersen, A; Bjerre, M; Chen, Z

2004-02-01

This paper considers the existence of multiple solutions to natural ventilation of a simple one-zone building, driven by combined thermal and opposing wind forces. The present analysis is an extension of an earlier analytical study of natural ventilation in a fully mixed building, and includes the effect of thermal stratification. Both computational and experimental investigations were carried out in parallel with an analytical investigation. When flow is dominated by thermal buoyancy, it was found experimentally that there is thermal stratification. When the flow is wind-dominated, the room is fully mixed. Results from all three methods have shown that the hysteresis phenomena exist. Under certain conditions, two different stable steady-state solutions are found to exist by all three methods for the same set of parameters. As shown by both the computational fluid dynamics (CFD) and experimental results, one of the solutions can shift to another when there is a sufficient perturbation. These results have probably provided the strongest evidence so far for the conclusion that multiple states exist in natural ventilation of simple buildings. Different initial conditions in the CFD simulations led to different solutions, suggesting that caution must be taken when adopting the commonly used 'zero initialization'.

Ventilation systems

International Nuclear Information System (INIS)

Gossler

1980-01-01

The present paper deals with - controlled area ventilation systems - ventilation systems for switchgear-building and control-room - other ventilation systems for safety equipments - service systems for ventilation systems. (orig./RW)

Demand Controlled Ventilation in a Combined Ventilation and Radiator System

OpenAIRE

Hesaraki, Arefeh; Holmberg, Sture

2013-01-01

With growing concerns for efficient and sustainable energy treatment in buildings there is a need for balanced and intelligent ventilation solutions. This paper presents a strategy for demand controlled ventilation with ventilation radiators, a combined heating and ventilation system. The ventilation rate was decreased from normal requirements (per floor area) of 0.375 l·s-1·m-2 to 0.100 l·s-1·m-2 when the residence building was un-occupied. The energy saving potential due to decreased ventil...

Airborne Particulate Matter in Two Multi-Family Green Buildings: Concentrations and Effect of Ventilation and Occupant Behavior.

Science.gov (United States)

Patton, Allison P; Calderon, Leonardo; Xiong, Youyou; Wang, Zuocheng; Senick, Jennifer; Sorensen Allacci, MaryAnn; Plotnik, Deborah; Wener, Richard; Andrews, Clinton J; Krogmann, Uta; Mainelis, Gediminas

2016-01-20

There are limited data on air quality parameters, including airborne particulate matter (PM) in residential green buildings, which are increasing in prevalence. Exposure to PM is associated with cardiovascular and pulmonary diseases, and since Americans spend almost 90% of their time indoors, residential exposures may substantially contribute to overall airborne PM exposure. Our objectives were to: (1) measure various PM fractions longitudinally in apartments in multi-family green buildings with natural (Building E) and mechanical (Building L) ventilation; (2) compare indoor and outdoor PM mass concentrations and their ratios (I/O) in these buildings, taking into account the effects of occupant behavior; and (3) evaluate the effect of green building designs and operations on indoor PM. We evaluated effects of ventilation, occupant behaviors, and overall building design on PM mass concentrations and I/O. Median PMTOTAL was higher in Building E (56 µg/m³) than in Building L (37 µg/m³); I/O was higher in Building E (1.3-2.0) than in Building L (0.5-0.8) for all particle size fractions. Our data show that the building design and occupant behaviors that either produce or dilute indoor PM (e.g., ventilation systems, combustion sources, and window operation) are important factors affecting residents' exposure to PM in residential green buildings.

Building America Case Study: Selecting Ventilation Systems for Existing Homes (Fact Sheet)

Energy Technology Data Exchange (ETDEWEB)

2014-12-01

This document addresses adding -or improving - mechanical ventilation systems to existing homes. The purpose of ventilation is to remove contaminants from homes, and this report discusses where, when, and how much ventilation is appropriate in a home, including some discussion of relevant codes and standards. Advantages, disadvantages, and approximate costs of various system types are presented along with general guidelines for implementing the systems in homes. CARB intends for this document to be useful to decision makers and contractors implementing ventilation systems in homes. Choosing the "best" system is not always straightforward; selecting a system involves balancing performance, efficiency, cost, required maintenance, and several other factors. It is the intent of this document to assist contractors in making more informed decisions when selecting systems. Ventilation is an integral part of a high-performance home. With more air-sealed envelopes, a mechanical means of removing contaminants is critical for indoor environmental quality and building durability.

Airborne Particulate Matter in Two Multi-Family Green Buildings: Concentrations and Effect of Ventilation and Occupant Behavior

Directory of Open Access Journals (Sweden)

Allison P. Patton

2016-01-01

Full Text Available There are limited data on air quality parameters, including airborne particulate matter (PM in residential green buildings, which are increasing in prevalence. Exposure to PM is associated with cardiovascular and pulmonary diseases, and since Americans spend almost 90% of their time indoors, residential exposures may substantially contribute to overall airborne PM exposure. Our objectives were to: (1 measure various PM fractions longitudinally in apartments in multi-family green buildings with natural (Building E and mechanical (Building L ventilation; (2 compare indoor and outdoor PM mass concentrations and their ratios (I/O in these buildings, taking into account the effects of occupant behavior; and (3 evaluate the effect of green building designs and operations on indoor PM. We evaluated effects of ventilation, occupant behaviors, and overall building design on PM mass concentrations and I/O. Median PMTOTAL was higher in Building E (56 µg/m3 than in Building L (37 µg/m3; I/O was higher in Building E (1.3–2.0 than in Building L (0.5–0.8 for all particle size fractions. Our data show that the building design and occupant behaviors that either produce or dilute indoor PM (e.g., ventilation systems, combustion sources, and window operation are important factors affecting residents’ exposure to PM in residential green buildings.

Moisture condensation on building envelopes in differential ventilated spaces in the tropics: quantitative assessment of influencing factors

Directory of Open Access Journals (Sweden)

Ali Maisarah

2016-01-01

Full Text Available Ventilation systems play a significant role in maintaining the indoor thermal and hygric balance. Nevertheless, the systems had been implicated to result in many problems. In the tropical climate, especially for energy efficiency purposes, building spaces are operated with differential ventilation. Such spaces operate on 24-hrs basis, some on 8-hrs while others are either naturally ventilated or served with mechanical supply-exhaust fan systems with non-conditioned outdoor air. This practice had been found to result in condensation problems. This study involves a quantitative appraisal of the effect of operative conditions and hygrothermal quality of building envelopes on condensation risk. The in-situ experiment is combined with an analytical approach to assessing the hygrothermal quality of building envelopes in a tropical climate building under differential ventilation between adjacent spaces. The case-studied building is with a known history of condensation and associated damages including mould growth. The microclimate measurement and hygrothermal performance of the wall and floor against condensation and mould growth risks had been previously reported elsewhere. As a step further, the present study evaluates the effects of various envelope insulation types and configurations together with the HVAC cooling set-points on envelope hygrothermal performance. The results revealed that overcooling the air-conditioned side increases condensation risk on the non-air-conditioned side of the envelopes. The envelopes failed criteria for surface condensation at existing operative conditions irrespective of envelope hygrothermal quality improvements. However, the envelope performed well at improved cooling operative conditions even at existing envelope hygrothermal quality. It is, therefore, important to ascertain the envelope hygrothermal quality as well the cooling operative conditions while embarking on energy efficiency operations in mechanical

Particle size distribution and composition in a mechanically ventilated school building during air pollution episodes.

Science.gov (United States)

Parker, J L; Larson, R R; Eskelson, E; Wood, E M; Veranth, J M

2008-10-01

Particle count-based size distribution and PM(2.5) mass were monitored inside and outside an elementary school in Salt Lake City (UT, USA) during the winter atmospheric inversion season. The site is influenced by urban traffic and the airshed is subject to periods of high PM(2.5) concentration that is mainly submicron ammonium and nitrate. The school building has mechanical ventilation with filtration and variable-volume makeup air. Comparison of the indoor and outdoor particle size distribution on the five cleanest and five most polluted school days during the study showed that the ambient submicron particulate matter (PM) penetrated the building, but indoor concentrations were about one-eighth of outdoor levels. The indoor:outdoor PM(2.5) mass ratio averaged 0.12 and particle number ratio for sizes smaller than 1 microm averaged 0.13. The indoor submicron particle count and indoor PM(2.5) mass increased slightly during pollution episodes but remained well below outdoor levels. When the building was occupied the indoor coarse particle count was much higher than ambient levels. These results contribute to understanding the relationship between ambient monitoring station data and the actual human exposure inside institutional buildings. The study confirms that staying inside a mechanically ventilated building reduces exposure to outdoor submicron particles. This study supports the premise that remaining inside buildings during particulate matter (PM) pollution episodes reduces exposure to submicron PM. New data on a mechanically ventilated institutional building supplements similar studies made in residences.

Cooling of the Building Structure by Night-time Ventilation

DEFF Research Database (Denmark)

Artmann, Nikolai

In modern, extensively glazed office buildings, due to high solar and internal loads and increased comfort expectations, air conditioning is increasingly applied even in moderate and cold climates, like in Central and Northern Europe. Particularly in these cases, night-time ventilation is often......, without considering any building-specific parameters. A method for quantifying the climatic cooling potential (CCP) was developed based on degree-hours of the difference between building and external air temperature. Applying this method to climatic data of 259 stations shows very high night cooling...... potential over the whole of Northern Europe and still significant potential in Central, Eastern and even some regions of Southern Europe. However, due to the inherent stochastic properties of weather patterns, series of warmer nights can occur at some locations, where passive cooling by night...

Augmenting natural ventilation using solar heat and free cool energy for residential buildings

Directory of Open Access Journals (Sweden)

N. B. Geetha

2014-03-01

Full Text Available In many urban buildings ventilation is not sufficient that will increase the temperature and also create unhealthy atmosphere inside the room. In such buildings artificially induced ventilation through freely available energy promote comfort conditions by reducing the temperature by 2 to 3°C and also creating good circulation of fresh air inside the room. In the present work the concept of improving the ventilation by excess hot energy available during summer days from the solar flat plate collector and by storing cool energy available during the early morning hour in the Phase Change Material (PCM based storage system is attempted. An experimental setup is made to study the effect of improvement in natural ventilation and the results are reported. A visible reduction in temperature is observed through circulation of air from the bottom side of the room to the roof of the house using the stored hot and cool energy. A CFD analysis is also carried out using ANSYS-CFX software to simulate and evaluate the mass flow of air at the inlet and at the selected RTD location by matching the transient temperature profile of the simulated result with the experimental results at the selected RTD location.

Reducing Mortality from Terrorist Releases of Chemical and Biological Agents: I. Filtration for Ventilation Systems in Commercial Building

Energy Technology Data Exchange (ETDEWEB)

Thatcher, Tracy L.; Daisey, Joan M.

1999-09-01

There is growing concern about potential terrorist attacks involving releases of chemical and/or biological (CB) agents, such as sarin or anthrax, in and around buildings. For an external release, the CB agent can enter the building through the air intakes of a building's mechanical ventilation system and by infiltration through the building envelope. For an interior release in a single room, the mechanical ventilation system, which often recirculates some fraction of the air within a building, may distribute the released CB agent throughout the building. For both cases, installing building systems that remove chemical and biological agents may be the most effective way to protect building occupants. Filtration systems installed in the heating, ventilating and air-conditioning (HVAC) systems of buildings can significantly reduce exposures of building occupants in the event of a release, whether the release is outdoors or indoors. Reduced exposures can reduce the number of deaths from a terrorist attack. The purpose of this report is to provide information and examples of the design of filtration systems to help building engineers retrofit HVAC systems. The report also provides background information on the physical nature of CB agents and brief overviews of the basic principles of particle and vapor filtration.

Energy Performance of a Novel System Combining Natural Ventilation with Diffuse Ceiling Inlet and Thermally Activated Building Systems (TABS)

DEFF Research Database (Denmark)

Yu, Tao

and thermally activated building systems (TABS) for cooling and ventilation in future Danish office buildings. The new solution would have the special potential of using natural ventilation all year round even in the extremely cold seasons without any draught risk. The main focuses of this study are the energy...

Influence of the urban environment on the effectiveness of natural night-ventilation of an office building

NARCIS (Netherlands)

Ramponi, R.; Gaetani, I.; Angelotti, A.

2014-01-01

The effectiveness of natural night-ventilation in the urban environment depends on local climate characteristics, but also on solar shading and wind shielding effects of the surrounding buildings. However, the impact of the latter factors on the effectiveness of night-ventilation is often

Indoor environmental quality and ventilation in U.S. office buildings: A view of current issues

Energy Technology Data Exchange (ETDEWEB)

Fisk, W.J.

1994-11-01

Much of the current focus on indoor environmental quality and ventilation in US office buildings is a response to sick building syndrome and occupant complaints about building-related health symptoms, poor indoor air quality, and thermal discomfort. The authors know that serious ``sick-building`` problems occur in a significant number of US office buildings and that a significant proportion of the occupants in many normal (non-sick) buildings report building-related health symptoms. Concerns about the health effects of environmental tobacco smoke have also focused attention on the indoor environment. The major responses of industry and governments, underway at the present time, are to restrict smoking in offices, to attempt to reduce the emissions of indoor pollutants, and to improve the operation of heating, ventilating and air conditioning (HVAC) systems. Better air filtration, improved HVAC commissioning and maintenance, and increased provisions for individual control of HVAC are some of the improvements in HVAC that are currently being, evaluated. In the future, the potential for improved productivity and reduced airborne transmission of infectious disease may become the major driving force for improved indoor environments.

Effect of ventilation on perceived quality of air polluted by building materials. A summary of reported data

Energy Technology Data Exchange (ETDEWEB)

Wargocki, P.; Vondruskova, J. (International Centre for Indoor Environment and Energy, Dept. of Mechanical Engineering, DTU, Kgs. Lyngby (DK)); Knudsen, Henrik N. (Danish Building Research Institute, Aalborg Univ., Hoersholm (DK))

2007-02-15

This paper summarizes existing data on how varying ventilation rates affect the perceived quality of air polluted by building materials. This is done by reviewing literature dealing with exposure-response relationships, i.e. the log-linear relationships between the concentration of pollutants (exposure) and the perceived air quality (response). The reviewed data originate from studies with single building materials performed in small-scale ventilated chambers and from studies carried out in a full-scale setting resembling normal offices. Perceived air quality expressed in terms of acceptability as assessed by untrained panels was included. The results show that the exposure-response relationships vary for different building materials as regards the impact of changing ventilation rate on perceived air quality and the level of perceived air quality at a constant ventilation rate. This applies both for the data collected in small-scale and in full-scale experiments. The differences may be caused by the experimental conditions, psychological factors, physiological factors, and chemical/physical factors. A well controlled study taking these factors into account with several different building materials, is thus recommended to further study whether the observed results have practical significance. These experiments should be carried out under realistic fullscale conditions. (au)

Experimental and Numerical Studies of Solar Chimney for Ventilation in Low Energy Buildings

DEFF Research Database (Denmark)

Zha, Xinyu; Zhang, Jun; Qin, Menghao

2017-01-01

As an effective way to protect environment and save energy in buildings, passive ventilation method has generated intense interest for improving indoor thermal environment in recent years. Among these passive ventilation solutions, design of solar chimney in buildings is a promising approach...... the performance of a full-scale solar chimney in a real building in East-ern China. The measured performance is compared with theoretical calculation and numerical simulation. In a solar chimney of 6.2m length, 2.8m width and 0.35m air gap, the experimental results show that air flow rate of 70.6 m3/h~1887.6 m3/h...... can be achieved during the daytime in the testing day. Comparing measured value with theoretical value, the flow rate is generally lower than the theoretical value. By data analysis, the suggested discharge coefficient Cd of solar energy in real engineering project is 0.51. With the use...

Numerical analysis of the potential of using light radiant ceilings in combination with diffuse ventilation to achieve thermal comfort in NZEB buildings

DEFF Research Database (Denmark)

Krusaa, Marie Rugholm; Hviid, Christian Anker; Kolarik, Jakub

ceiling panels. These panels make it possible to combine the heating/cooling ceiling with the diffuse ventilation method. The diffuse ventilation method or leak ventilation use larger surfaces to provide air into the room instead of diffusers. An office building is investigated an analysed on an annual...... basis in the dynamic building simulation tool IDA Indoor Climate and Energy (IDA ICE). The office building contains both offices and meeting rooms. Worst-case scenarios are investigated in the office building considering heat gains, solar gains and the temperature offset between supply water temperature...

Solar Heat Gain Reduction of Ventilated Double Skin Windows without a Shading Device

Directory of Open Access Journals (Sweden)

Bokyoung Koo

2017-12-01

Full Text Available With global efforts to strengthen various energy-saving policies for buildings to reduce greenhouse gas emissions, in South Korea, new laws and regulations have been in force since May 2015 to install shading devices in public buildings and to include the solar heat gain coefficient (SHGC reduction performance of shading devices in the evaluation of building performance. By making a ventilated air layer outer glass and inner glass to lower the temperatures of the air layer and glass surface, it is possible to reduce the amount of heat flowing into the building while maintaining the same level of light transmission as plain window systems. This study proposes a double-skin façade window with a 20 mm ventilated air cavity, and assumes that insolation inflow indoors would be reduced through ventilation in the air cavity. The artificial solar lab test results show that the SHGC can be lowered through ventilation by 28% to 52.9%. Additionally, in an outdoor test cell experiment, the results show that the mean temperature was 0.6 K and the peak temperature was 0.9 K lower with ventilation in the air cavity than that without ventilation in the air cavity.

Ventilated air cavities for the control of rising damp in historical buildings. Functional analysis

Directory of Open Access Journals (Sweden)

Mª T. Gil Muñoz

2018-01-01

Full Text Available This study analyzes the behavior of ventilated air cavities and their level of efficiency when used for the control of rising damp and the associated pathological damage in walls and foundations of historical buildings. The methodology is based on experiments on-site and monitoring. Knowledge of local climate conditions, the surroundings of the building, its construction features and the type of foundation constitute the preliminary conditions for the monitoring. In order to reach the goal we have measured several parameters according to a plan, developed graphical tools for the study, and prepared statistical data. The building of this system has not always been accompanied by a thorough assessment that would justify the intervention. The results show how this situation has affected the design strategies and sizing of the ventilated air cavities, limiting in many cases their efficiency.

A Prospective Study of Ventilation Rates and Illness Absence in California Office Buildings

Energy Technology Data Exchange (ETDEWEB)

Eliseeva, Ekaterina A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Spears, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Chan, Wanyu R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Cohn, Sebastian [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sullivan, Douglas P. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2014-10-07

Background – This study investigated the associations of ventilation rates (VRs), estimated from indoor CO2 concentrations, in offices with the amount of respiratory infections, illness absences, and building-related health symptoms in occupants. Methods – Office buildings were recruited from three California climate zones. In one or more study spaces within each building, real-time logging sensors measured carbon dioxide, temperature, and relative humidity for one year. Ventilation rates were estimated using daily peak CO2 levels, and also using an alternative metric. Data on occupants and health outcomes were collected through web-based surveys every three months. Multivariate models were used to assess relationships between metrics of ventilation rate or CO2 and occupant outcomes. For all outcomes, negative associations were hypothesized with VR metrics, and positive associations with CO2 metrics. Results – Difficulty recruiting buildings and low survey response limited sample size and study power. In 16 studied spaces within 9 office buildings, VRs were uniformly high over the year, from twice to over nine times the California office VR standard (7 L/s or 15 cfm per person). VR and CO2 metrics had no statistically significant relationships with occupant outcomes, except for a small significantly positive association of the alternative VR metric with respiratory illness-related absence, contrary to hypotheses. Conclusions– The very high time-averaged VRs in the California office buildings studied presumably resulted from “economizer cycles” bringing in large volumes of outdoor air; however, in almost all buildings even the estimated minimum VRs supplied (without the economizer) substantially exceeded the minimum required VR. These high VRs may explain the absence of hypothesized relationships with occupant outcomes. Among uniformly high VRs, little variation in contaminant concentration and occupant effects would be expected. These findings may

Ultrafine and Fine Particulate Matter Inside and Outside of Mechanically Ventilated Buildings.

Science.gov (United States)

Miller, Shelly L; Facciola, Nick A; Toohey, Darin; Zhai, John

2017-01-28

The objectives of this study were to measure levels of particulate matter (PM) in mechanically ventilated buildings and to improve understanding of filtration requirements to reduce exposure. With the use of an Ultra High Sensitivity Aerosol Spectrometer and an Aerodyne Mass Spectrometer, ultrafine (0.055-0.1 μm) and fine (0.1-0.7 μm) indoor and outdoor PM was measured as a function of time in an office, a university building, and two elementary schools. Indoor particle levels were highly correlated with outdoor levels. Indoor and outdoor number concentrations in Denver were higher than those in Boulder, with the highest number concentrations occurring during summer and fall. The ratio of indoor-to-outdoor (I/O) PM was weakly but positively correlated with the amount of ventilation provided to the indoor environment, did not vary much with particle size (ranged between 0.48 and 0.63 for the entire size range), and was similar for each period of the week (weekend vs. weekday, night vs. day). Regression analyses showed that ultrafine indoor PM baseline concentrations were higher at night from nighttime infiltration. A lag time was observed between outdoor and indoor measurements. Weekday days had the shortest lag time of 11 min, and weekend nighttime lags when the HVAC was not in use were 50 to 148 min. Indoor-outdoor PM concentration plots showed ultrafine PM was more correlated compared to fine, and especially when the HVAC system was on. Finally, AMS data showed that most of the PM was organic, with occasional nitrate events occurring outdoors. During nitrate events, there were less indoor particles detected, indicating a loss of particulate phase nitrate. The results from this study show that improved filtration is warranted in mechanically ventilated buildings, particularly for ultrafine particles, and that nighttime infiltration is significant depending on the building design.

Climatic potential for passive cooling of buildings by night-time ventilation in Europe

DEFF Research Database (Denmark)

Artmann, Nikolai; Manz, H.; Heiselberg, Per

2006-01-01

Due to an overall trend towards less heating and more cooling demands in buildings in many European countries over the last few decades, passive cooling by night-time ventilation is seen as a promising technique, particularly for commercial buildings in the moderate or cold climates of Central......, without considering any building-specific parameters. An approach for calculating degree-hours based on a variable building temperature - within a standardized range of thermal comfort - is presented and applied to climatic data of 259 stations all over Europe. The results show a high potential for night...

Policy Pathways: Energy Performance Certification of Buildings

Energy Technology Data Exchange (ETDEWEB)

NONE

2010-07-01

Improving energy efficiency is one of the most effective measures to address energy security, climate change and economic objectives. The Policy Pathways series can help countries capture this potential by assisting with the implementation of the 25 energy efficiency policy recommendations that were published by the International Energy Agency (IEA) in 2008. This policy pathway on energy performance certification of buildings is the second in the series. It aims to provide a 'how-to' guide to policy makers and relevant stakeholders on the essential elements in implementing energy performance certification of buildings programmes. Energy performance certification of buildings is a way to rate the energy efficiency of individual buildings -- whether they be residential, commercial or public. It is a key policy instrument that can assist governments in reducing energy consumption in buildings. This policy pathway showcases experiences from countries around the world to show examples of good practice and delivers a pathway of ten critical steps to implement energy performance certification of buildings programmes.

Ventilation in Commercial and Residential Buildings

DEFF Research Database (Denmark)

Nielsen, Peter V.

A number of areas have to be considered in connection with indoor air quality and ventilation. The selection of ventilation principle and components in the ventilation system will have influence on the indoor air quality and this subject will be discussed on the following pages. The main object o...

Low-energy mechanical ventilation

DEFF Research Database (Denmark)

Andersen, Claus Wessel; Hviid, Christian Anker

2014-01-01

and with as little energy consumption as 41.1 kWh/m2/year including heating and all building services with no use of renewable energy such as PVcells or solar heating. One of the key means of reaching the objectives was to implement mechanical ventilation with low pressure loss and therefore low energy consumption....... The project consists of two buildings, building one is 6 stories high, and building two is 4 stories high. The buildings have a gross area of 50,500 m2 including underground parking. The ventilation and indoor climate concept was to use mechanical ventilation together with mechanical cooling and fanassisted......, with an average of 1.1 kJ/m3. The yearly mean SFP based on estimated runtime is approx. 0.8 kJ/m3. The case shows the unlocked potential that lies within mechanical ventilation for nearzero energy consuming buildings....

CO2 MONITORING FOR DEMAND CONTROLLED VENTILATION IN COMMERCIAL BUILDINGS

Energy Technology Data Exchange (ETDEWEB)

Fisk, William J.; Sullivan, Douglas P.; Faulkner, David; Eliseeva, Ekaterina

2010-03-17

Carbon dioxide (CO{sub 2}) sensors are often deployed in commercial buildings to obtain CO{sub 2} data that are used, in a process called demand-controlled ventilation, to automatically modulate rates of outdoor air ventilation. The objective is to keep ventilation rates at or above design specifications and code requirements and also to save energy by avoiding excessive ventilation rates. Demand controlled ventilation is most often used in spaces with highly variable and sometime dense occupancy. Reasonably accurate CO{sub 2} measurements are needed for successful demand controlled ventilation; however, prior research has suggested substantial measurement errors. Accordingly, this study evaluated: (a) the accuracy of 208 CO{sub 2} single-location sensors located in 34 commercial buildings, (b) the accuracy of four multi-location CO{sub 2} measurement systems that utilize tubing, valves, and pumps to measure at multiple locations with single CO{sub 2} sensors, and (c) the spatial variability of CO{sub 2} concentrations within meeting rooms. The field studies of the accuracy of single-location CO{sub 2} sensors included multi-concentration calibration checks of 90 sensors in which sensor accuracy was checked at multiple CO{sub 2} concentrations using primary standard calibration gases. From these evaluations, average errors were small, -26 ppm and -9 ppm at 760 and 1010 ppm, respectively; however, the averages of the absolute values of error were 118 ppm (16%) and 138 ppm (14%), at concentrations of 760 and 1010 ppm, respectively. The calibration data are generally well fit by a straight line as indicated by high values of R{sup 2}. The Title 24 standard specifies that sensor error must be certified as no greater than 75 ppm for a period of five years after sensor installation. At 1010 ppm, 40% of sensors had errors greater than {+-}75 ppm and 31% of sensors has errors greater than {+-}100 ppm. At 760 ppm, 47% of sensors had errors greater than {+-}75 ppm and 37% of

Ventilative Cooling

DEFF Research Database (Denmark)

Heiselberg, Per Kvols; Kolokotroni, Maria

This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state-of-the-art of ventil......This report, by venticool, summarises the outcome of the work of the initial working phase of IEA ECB Annex 62 Ventilative Cooling and is based on the findings in the participating countries. It presents a summary of the first official Annex 62 report that describes the state......-of-the-art of ventilative cooling potentials and limitations, its consideration in current energy performance regulations, available building components and control strategies and analysis methods and tools. In addition, the report provides twenty six examples of operational buildings using ventilative cooling ranging from...

Potential for passive cooling of buildings by night-time ventilation in present and future climates in Europe

DEFF Research Database (Denmark)

Artmann, Nikolai; Manz, Heinrich; Heiselberg, Per

2006-01-01

Given the general shift in recent decades towards a lower heating and higher cooling demand for buildings in many European countries, passive cooling by night-time ventilation has come to be seen as a promising option, particularly in the moderate or cold climates of Central, Eastern and Northern...... Europe. The basic concept involves cooling the building structure overnight in order to provide a heat sink that is available during the occupancy period. In this study, the potential for the passive cooling of buildings by night-time ventilation is evaluated by analysing climatic data, irrespective...... of any building-specific parameters. An approach for calculating degree-hours based on a variable building temperature - within a standardized range of thermal comfort - is presented and applied to climatic data from 259 stations throughout Europe. The results show a very high potential for night...

Indoor air quality in mechanically ventilated residential dwellings/low-rise buildings: A review of existing information

DEFF Research Database (Denmark)

Aganovic, Amar; Hamon, Mathieu; Kolarik, Jakub

Mechanical ventilation has become a mandatory requirement in multiple European standards addressing indoor air quality (IAQ) and ventilation in residential dwellings (single family houses and low-rise apartment buildings). This article presents the state of the art study through a review...... of the existing literature, to establish a link between ventilation rate and key indoor air pollutants. Design characteristics of a mechanical ventilation system such as supply/exhaustairflow, system and design of supply and exhaust outlets were considered. The performance of various ventilation solutionswas......-house ventilation rate was reported below 0.5h-1 or 14 l/s·person in bedrooms, the concentrations of the pollutants elevated above minimum threshold limits (CO2>1350 ppm; TVOC >3000 μg/m3) defined by the standard. Insufficient or non-existent supply of air was related to significantly higher pollutant...

Energy and IAQ Implications of Alternative Minimum Ventilation Rates in California Retail and School Buildings

Energy Technology Data Exchange (ETDEWEB)

Dutton, Spencer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fisk, William J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-01-01

For a stand-alone retail building, a primary school, and a secondary school in each of the 16 California climate zones, the EnergyPlus building energy simulation model was used to estimate how minimum mechanical ventilation rates (VRs) affect energy use and indoor air concentrations of an indoor-generated contaminant. The modeling indicates large changes in heating energy use, but only moderate changes in total building energy use, as minimum VRs in the retail building are changed. For example, predicted state-wide heating energy consumption in the retail building decreases by more than 50% and total building energy consumption decreases by approximately 10% as the minimum VR decreases from the Title 24 requirement to no mechanical ventilation. The primary and secondary schools have notably higher internal heat gains than in the retail building models, resulting in significantly reduced demand for heating. The school heating energy use was correspondingly less sensitive to changes in the minimum VR. The modeling indicates that minimum VRs influence HVAC energy and total energy use in schools by only a few percent. For both the retail building and the school buildings, minimum VRs substantially affected the predicted annual-average indoor concentrations of an indoor generated contaminant, with larger effects in schools. The shape of the curves relating contaminant concentrations with VRs illustrate the importance of avoiding particularly low VRs.

A method for evaluating the problem complex of choosing the ventilation system for a new building

DEFF Research Database (Denmark)

Hviid, Christian Anker; Svendsen, Svend

2007-01-01

The application of a ventilation system in a new building is a multidimensional complex problem that involves quantifiable and non-quantifiable data like energy consump¬tion, indoor environment, building integration and architectural expression. This paper presents a structured method for evaluat...

Policy Pathways: Modernising Building Energy Codes

Energy Technology Data Exchange (ETDEWEB)

NONE

2013-08-01

Buildings are the largest consumers of energy worldwide and will continue to be a source of increasing energy demand in the future. Globally, the sector’s final energy consumption doubled between 1971 and 2010 to reach 2 794 million tonnes of oil equivalent (Mtoe), driven primarily by population increase and economic growth. Under current policies, the global energy demand of buildings is projected by the IEA experts to grow by an additional 838 Mtoe by 2035 compared to 2010. The challenges of the projected increase of energy consumption due to the built environment vary by country. In IEA member countries, much of the future buildings stock is already in place, and so the main challenge is to renovate existing buildings stock. In non-IEA countries, more than half of the buildings stock needed by 2050 has yet to be built. The IEA and the UNDP partnered to analyse current practices in the design and implementation of building energy codes. The aim is to consolidate existing efforts and to encourage more attention to the role of the built environment in a low-carbon and climate-resilient world. This joint IEA-UNDP Policy Pathway aims to share lessons learned between IEA member countries and non-IEA countries. The objective is to spread best practices, limit pressures on global energy supply, improve energy security, and contribute to environmental sustainability. Part of the IEA Policy Pathway series, Modernising building energy codes to secure our global energy future sets out key steps in planning, implementation, monitoring and evaluation. The Policy Pathway series aims to help policy makers implement the IEA 25 Energy Efficiency Policy Recommendations endorsed by IEA Ministers (2011).

Energy saving potential of natural ventilation in China: The impact of ambient air pollution

International Nuclear Information System (INIS)

Tong, Zheming; Chen, Yujiao; Malkawi, Ali; Liu, Zhu; Freeman, Richard B.

2016-01-01

Highlights: • Natural ventilation potential is affected largely by ambient air pollution in China. • NV hours of 76 Chinese cities based on weather and ambient air quality are estimated. • Cooling energy savings and carbon reductions of 35 major Chinese cities are estimated. • 8–78% of the cooling energy usage can be potentially reduced by NV. • Our findings provide guidelines to improve energy policies in China. - Abstract: Natural ventilation (NV) is a key sustainable solution for reducing the energy use in buildings, improving thermal comfort, and maintaining a healthy indoor environment. However, the energy savings and environmental benefits are affected greatly by ambient air pollution in China. Here we estimate the NV potential of all major Chinese cities based on weather, ambient air quality, building configuration, and newly constructed square footage of office buildings in the year of 2015. In general, little NV potential is observed in northern China during the winter and southern China during the summer. Kunming located in the Southwest China is the most weather-favorable city for natural ventilation, and reveals almost no loss due to air pollution. Building Energy Simulation (BES) is conducted to estimate the energy savings of natural ventilation in which ambient air pollution and total square footage at each city must be taken into account. Beijing, the capital city, displays limited per-square-meter saving potential due to the unfavorable weather and air quality for natural ventilation, but its largest total square footage of office buildings makes it become the city with the greatest energy saving opportunity in China. Our analysis shows that the aggregated energy savings potential of office buildings at 35 major Chinese cities is 112 GWh in 2015, even after allowing for a 43 GWh loss due to China’s serious air pollution issue especially in North China. 8–78% of the cooling energy consumption can be potentially reduced by natural

Ventilation system in the RA reactor building - design specifications; Sistem ventilacije u objektu 'RA' - Tehnicki opis

Energy Technology Data Exchange (ETDEWEB)

Badrljica, R [Institute of Nuclear Sciences Boris Kidric, Vinca, Beograd (Serbia and Montenegro)

1984-09-15

Protective role of the ventilation system of nuclear facilities involve construction of ventilation barriers which prevent release of radioactive particulates or gases, elimination od radioactive particulates and gases from the air which is released from contaminated zones into the reactor environment. Ventilation barriers are created by dividing the building into a number of ventilation zones with different sub pressure compared to the atmospheric pressure. The RA reactor building is divided into four ventilation zones. First zone is the zone of highest risk. It includes reactor core with horizontal experimental channels, underground rooms of the primary coolant system (D{sub 2}O), helium system, hot cells and the space above the the reactor core. Second zone is the reactor hall and the room for irradiated fuel storage. The third zone includes corridors in the basement, ground floor and first floor where the probability of contamination is small. The fourth zone includes the annex where the contamination risk is low. There is no have natural air circulation in the reactor building. Ventilators for air input and outlet maintain the sub pressure in the building (pressure lower than the atmospheric pressure). This prevents release of radioactivity into the atmosphere. Zastitne uloge ventilacionog sistema kod nuklearnih postrojenja obuhvataju formiranje ventilacionih barijera koje onemugucavaju sirenje radioaktivnih cestica ili gasova putem cirkulacije vazduha; eliminaciju radioaktivnih cestica i gasova iz vazduha koji se evakuise iz kontaminiranih prostora u okolinu reaktorskog postrojenja. Formiranje zastitnih ventilacionih barijera ostvaruje se obicno podelom unutrasnjosti objekta na vise ventilacionih zona razlicitih podpritisaka u odnosu na spoljni atmosferski pritisak. Celi prostor zgrade reaktora RA podeljen je u cetiri ventilacione zone. Prva zona je zona najveceg rizika, u koju spadaju reaktorsko jezgro sa horizontalnim eksperimentalnim kanalima, tehnoloske

Influence of placement and height of high-rise buildings on wind pressure distribution and natural ventilation of low- and medium-rise buildings

Czech Academy of Sciences Publication Activity Database

Kuznetsov, Sergeii; Butova, A.; Pospíšil, Stanislav

2016-01-01

Roč. 15, 3/4 (2016), s. 253-266 ISSN 1473-3315 R&D Projects: GA ČR(CZ) GA14-12892S; GA MŠk(CZ) LO1219 Keywords : natural ventilation * high-rise building s * low- and medium-rise building s * wind pressure coefficient * wind tunnel tests Subject RIV: JM - Building Engineering Impact factor: 0.391, year: 2016 http://www.tandfonline.com/doi/full/10.1080/14733315.2016.1214396

Numerical analysis of passive strategies for energy retrofit of existing buildings in Mediterranean climate: thermal mass and natural ventilation combination

Directory of Open Access Journals (Sweden)

Calcerano Filippo

2017-01-01

Full Text Available The study investigates the potential of coupling natural ventilation and thermal storage systems to improve hygrothermal comfort and reduce energy consumption during summer season in an existing building in the Mediterranean. It aims at bridging the knowledge gap between designers, researchers and building scientists, fostering a multidisciplinary approach and promoting numerical simulation of the energy performance of buildings within architectural professional practice. The study analyses the interaction between six natural ventilation systems (single sided ventilation through facade openings; cross ventilation through facade openings, inlet wind tower, thermal chimney, evaporative cool tower, earth pipes and with two thermal storage typology (heavy and medium-light within four strategic Italian location (Rome, Naples, Messina and Catania. For each interaction we perform a numerical dynamic simulation of indoor comfort, indoor air quality and energy consumption during the summer period, on a reference building model corresponding to the most common Italian typology. Results show that the use of the chosen systems ensures significant reductions of discomfort hours and energy consumption in all configurations. The study also highlights the high efficiency of non invasive systems (single-sided and cross ventilation with automatic control present discomfort hours reduction and energy consumption reduction above 68% for all combinations and the significant influence of the daily thermal range value on the performance of systems without air pre-treatment.

Optimization of a solar chimney design to enhance natural ventilation in a multi-storey office building

NARCIS (Netherlands)

Gontikaki, M.; Trcka, M.; Hensen, J.L.M.; Hoes, P.

2010-01-01

Natural ventilation of buildings can be achieved with solar-driven, buoyancy-induced airflow through a solar chimney channel. Research on solar chimneys has covered a wide range of topics, yet study of the integration in multi-storey buildings has been performed in few numerical studies, where

Multifamily Ventilation Retrofit Strategies

Energy Technology Data Exchange (ETDEWEB)

Ueno, K. [Building Science Corporation (BSC), Somerville, MA (United States); Lstiburek, J. [Building Science Corporation (BSC), Somerville, MA (United States); Bergey, D. [Building Science Corporation (BSC), Somerville, MA (United States)

2012-12-01

In multifamily buildings, central ventilation systems often have poor performance, overventilating some portions of the building (causing excess energy use), while simultaneously underventilating other portions (causing diminished indoor air quality). BSC and Innova Services Corporation performed a series of field tests at a mid-rise test building undergoing a major energy audit and retrofit, which included ventilation system upgrades.

Summary of human responses to ventilation

Energy Technology Data Exchange (ETDEWEB)

Seppanen, Olli A.; Fisk, William J.

2004-06-01

The effects of ventilation on indoor air quality and health is a complex issue. It is known that ventilation is necessary to remove indoor generated pollutants from indoor air or dilute their concentration to acceptable levels. But, as the limit values of all pollutants are not known, the exact determination of required ventilation rates based on pollutant concentrations and associated risks is seldom possible. The selection of ventilation rates has to be based also on epidemiological research (e.g. Seppanen et al., 1999), laboratory and field experiments (e.g. CEN 1996, Wargocki et al., 2002a) and experience (e.g. ECA 2003). Ventilation may also have harmful effects on indoor air quality and climate if not properly designed, installed, maintained and operated as summarized by Seppdnen (2003). Ventilation may bring indoors harmful substances that deteriorate the indoor environment. Ventilation also affects air and moisture flow through the building envelope and may lead to moisture problems that deteriorate the structures of the building. Ventilation changes the pressure differences over the structures of building and may cause or prevent the infiltration of pollutants from structures or adjacent spaces. Ventilation is also in many cases used to control the thermal environment or humidity in buildings. Ventilation can be implemented with various methods which may also affect health (e.g. Seppdnen and Fisk, 2002, Wargocki et al., 2002a). In non residential buildings and hot climates, ventilation is often integrated with air-conditioning which makes the operation of ventilation system more complex. As ventilation is used for many purposes its health effects are also various and complex. This paper summarizes the current knowledge on positive and negative effects of ventilation on health and other human responses. The focus of the paper is on office-type working environment and residential buildings. In the industrial premises the problems of air quality are usually

Ventilation strategies and indoor environment in classrooms

DEFF Research Database (Denmark)

Zhang, Chen; Liu, Li

2017-01-01

Compared with the other building types, the school building has much higher occupancy density and ventilation demand. In Demark, most of the school buildings are ventilated by natural manner. There is a risk of poor indoor environment associated with the lack of ventilation system or insufficient...

Demand controlled ventilation; Behovsstyrt ventilasjon

Energy Technology Data Exchange (ETDEWEB)

Soerensen, Henning Holm

2006-07-01

The terms CAV and VAV have been known terms for many years in the ventilation business. The terms are also included in building regulations, but the time is now right to focus on demand controlled ventilation (DCV). The new building regulations and the accompanying energy framework underline the need for a more nuanced thinking when it comes to controlling ventilation systems. Descriptions and further details of the ventilation systems are provided (ml)

Indoor air quality and occupant satisfaction in five mechanically and four naturally ventilated open-plan office buildings

DEFF Research Database (Denmark)

Hummelgaard, J.; Juhl, P.; Saebjornsson, K.O.

2007-01-01

Occupant responses and indoor environment characteristics were recorded and compared in five mechanically and four naturally ventilated open-plan office buildings by using a simple approach that enabled us to survey many buildings simultaneously. All occupant responses were obtained during one...

Wind Extraction for Natural Ventilation

Science.gov (United States)

Fagundes, Tadeu; Yaghoobian, Neda; Kumar, Rajan; Ordonez, Juan

2017-11-01

Due to the depletion of energy resources and the environmental impact of pollution and unsustainable energy resources, energy consumption has become one of the main concerns in our rapidly growing world. Natural ventilation, a traditional method to remove anthropogenic and solar heat gains, proved to be a cost-effective, alternative method to mechanical ventilation. However, while natural ventilation is simple in theory, its detailed design can be a challenge, particularly for wind-driven ventilation, which its performance highly involves the buildings' form, surrounding topography, turbulent flow characteristics, and climate. One of the main challenges with wind-driven natural ventilation schemes is due to the turbulent and unpredictable nature of the wind around the building that impose complex pressure loads on the structure. In practice, these challenges have resulted in founding the natural ventilation mainly on buoyancy (rather than the wind), as the primary force. This study is the initial step for investigating the physical principals of wind extraction over building walls and investigating strategies to reduce the dependence of the wind extraction on the incoming flow characteristics and the target building form.

Design of Natural and Hybrid Ventilation

DEFF Research Database (Denmark)

Heiselberg, Per

The effectiveness of natural ventilation, i.e. its ability to ensure indoor air quality and passive cooling in a building, depends greatly on the design process. Mechanical ventilation systems can be designed separately from the design of the building in which they are installed. They can also...... be installed in existing buildings after a few modifications. In contrast, ventilation systems using only natural forces such as wind and thermal buoyancy need to be designed together with the building, since the building itself and its components are the elements that can reduce or increase air movement...... as well as influence the air content (dust, pollution etc.). Architects and engineers need to acquire qualitative and quantitative information about the interactions between building characteristics and natural ventilation in order to design buildings and systems consistent with a passive low...

Modelling of Natural and Hybrid Ventilation

DEFF Research Database (Denmark)

Heiselberg, Per

The effectiveness of natural ventilation, i.e. its ability to ensure indoor air quality and passive cooling in a building, depends greatly on the design process. Mechanical ventilation systems can be designed separately from the design of the building in which they are installed. They can also...... be installed in existing buildings after a few modifications. In contrast, ventilation systems using only natural forces such as wind and thermal buoyancy need to be designed together with the building, since the building itself and its components are the elements that can reduce or increase air movement...... as well as influence the air content (dust, pollution etc.). Architects and engineers need to acquire qualitative and quantitative information about the interactions between building characteristics and natural ventilation in order to design buildings and systems consistent with a passive low...

Design Procedure for Hybrid Ventilation

DEFF Research Database (Denmark)

Heiselberg, Per; Tjelflaat, Per Olaf

Mechanical and natural ventilation systems have developed separately during many years. The natural next step in this development is development of ventilation concepts that utilises and combines the best features from each system into a new type of ventilation system - Hybrid Ventilation....... Buildings with hybrid ventilation often include other sustainable technologies and an energy optimisation requires an integrated approach in the design of the building and its mechanical systems. Therefore, the hybrid ventilation design procedure differs from the design procedure for conventional HVAC....... The first ideas on a design procedure for hybrid ventilation is presented and the different types of design methods, that is needed in different phases of the design process, is discussed....

Modelling of Natural and Hybrid Ventilation

OpenAIRE

Heiselberg, Per

2006-01-01

The effectiveness of natural ventilation, i.e. its ability to ensure indoor air quality and passive cooling in a building, depends greatly on the design process. Mechanical ventilation systems can be designed separately from the design of the building in which they are installed. They can also be installed in existing buildings after a few modifications. In contrast, ventilation systems using only natural forces such as wind and thermal buoyancy need to be designed together with the building,...

Building America Top Innovations 2014 Profile: ASHRAE Standard 62.2. Ventilation and Acceptable Indoor Air Quality in Low-Rise Residential Buildings

Energy Technology Data Exchange (ETDEWEB)

none,

2014-11-01

This 2014 Top Innovations profile describes Building America research and support in developing and gaining adoption of ASHRAE 62.2, a residential ventilation standard that is critical to transforming the U.S. housing industry to high-performance homes.

Simulations of the impacts of building height layout on air quality in natural-ventilated rooms around street canyons.

Science.gov (United States)

Yang, Fang; Zhong, Ke; Chen, Yonghang; Kang, Yanming

2017-10-01

Numerical simulations were conducted to investigate the effects of building height ratio (i.e., HR, the height ratio of the upstream building to the downstream building) on the air quality in buildings beside street canyons, and both regular and staggered canyons were considered for the simulations. The results show that the building height ratio affects not only the ventilation fluxes of the rooms in the downstream building but also the pollutant concentrations around the building. The parameter, outdoor effective source intensity of a room, is then proposed to calculate the amount of vehicular pollutants that enters into building rooms. Smaller value of this parameter indicates less pollutant enters the room. The numerical results reveal that HRs from 2/7 to 7/2 are the favorable height ratios for the regular canyons, as they obtain smaller values than the other cases. While HR values of 5/7, 7/7, and 7/5 are appropriate for staggered canyons. In addition, in terms of improving indoor air quality by natural ventilation, the staggered canyons with favorable HR are better than those of the regular canyons.

Exploring Ventilation Efficiency in Poultry Buildings: The Validation of Computational Fluid Dynamics (CFD in a Cross-Mechanically Ventilated Broiler Farm

Directory of Open Access Journals (Sweden)

Antonio Hospitaler

2013-05-01

Full Text Available Broiler production in modern poultry farms commonly uses mechanical ventilation systems. This mechanical ventilation requires an amount of electric energy and a high level of investment in technology. Nevertheless, broiler production is affected by periodic problems of mortality because of thermal stress, thus being crucial to explore the ventilation efficiency. In this article, we analyze a cross-mechanical ventilation system focusing on air velocity distribution. In this way, two methodologies were used to explore indoor environment in livestock buildings: Computational Fluid Dynamics (CFD simulations and direct measurements for verification and validation (V&V of CFD. In this study, a validation model using a Generalized Linear Model (GLM was conducted to compare these methodologies. The results showed that both methodologies were similar in results: the average of air velocities values were 0.60 ± 0.56 m s−1 for CFD and 0.64 ± 0.54 m s−1 for direct measurements. In conclusion, the air velocity was not affected by the methodology (CFD or direct measurements, and the CFD simulations were therefore validated to analyze indoor environment of poultry farms and its operations. A better knowledge of the indoor environment may contribute to reduce the demand of electric energy, increasing benefits and improving the thermal comfort of broilers.

The fluid mechanics of natural ventilation

Science.gov (United States)

Linden, Paul

1999-11-01

Natural ventilation of buildings is the flow generated by temperature differences and by the wind. Modern buildings have extreme designs with large, tall open plan spaces and large cooling requirements. Natural ventilation offers a means of cooling these buildings and providing good indoor air quality. The essential feature of ventilation is an exchange between an interior space and the external ambient. Recent work shows that in many circumstances temperature variations play a controlling feature on the ventilation since the directional buoyancy force has a large influence on the flow patterns within the space and on the nature of the exchange with the outside. Two forms of buoyancy-driven ventilation are discussed: mixing ventilation in which the interior is at approximately uniform temperature and displacement ventilation where there is strong internal stratification. The dynamics of these flows are considered and the effects of wind on them are examined both experimentally and theoretically. The aim behind this work is to give designers rules and intuition on how air moves within a building and the research shows a fascinating branch of fluid mechanics.

Energy saving technologies of the decentralized ventilation of buildings

Science.gov (United States)

Mansurov, R. Sh; Rafalskaya, T. A.

2017-11-01

The growing aspiration to energy saving and efficiency of energy leads to necessity to build tight enough buildings. As a result of this the quantity of infiltration air appears insufficient for realization of necessary air exchange in. One of decisions of the given problem is development and application for ventilation of premises of the decentralized forced-air and exhaust systems (DFAES) with recuperative or regenerative heat-exchangers. For an estimation of efficiency of DFAES following basic parameters have been certain: factor of energy saving; factor of efficiency of energy; factor of a heat transfer; factor of an effective utilization of a surface of heat exchange. Were estimated temperature of forced air; actual speed of an air jet on an entrance in a served zone; actual noise level; the charge of external air. Tests of DFAES were spent in natural conditions at which DFAES influenced all set of factors both an external climate, and an internal microclimate of a premise, and also the arrangement on a wind side or behind wind side of a building, influence of surrounding building, fluctuation of temperature of external air is considered. Proceeding from results and the analysis of the lead researches recommendations have been developed for development and manufacture of new sample of DFAES.

The ICU trial: a new admission policy for cancer patients requiring mechanical ventilation.

Science.gov (United States)

Lecuyer, Lucien; Chevret, Sylvie; Thiery, Guillaume; Darmon, Michael; Schlemmer, Benoît; Azoulay, Elie

2007-03-01

Cancer patients requiring mechanical ventilation are widely viewed as poor candidates for intensive care unit (ICU) admission. We designed a prospective study evaluating a new admission policy titled The ICU Trial. Prospective study. Intensive care unit. One hundred eighty-eight patients requiring mechanical ventilation and having at least one other organ failure. Over a 3-yr period, all patients with hematologic malignancies or solid tumors proposed for ICU admission underwent a triage procedure. Bedridden patients and patients in whom palliative care was the only cancer treatment option were not admitted to the ICU. Patients at earliest phase of the malignancy (diagnosis ventilation, vasopressors, or dialysis after 3 days in the ICU died. Survival was 40% in mechanically ventilated cancer patients who survived to day 5 and 21.8% overall. If these results are confirmed in future interventional studies, we recommend ICU admission with full-code management followed by reappraisal on day 6 in all nonbedridden cancer patients for whom lifespan-extending cancer treatment is available.

Ventilation effectiveness

CERN Document Server

Mathisen, Hans Martin; Nielsen, Peter V; Moser, Alfred

2004-01-01

Improving the ventilation effectiveness allows the indoor air quality to be significantly enhanced without the need for higher air changes in the building, thereby avoiding the higher costs and energy consumption associated with increasing the ventilation rates. This Guidebook provides easy-to-understand descriptions of the indices used to mesure the performance of a ventilation system and which indices to use in different cases.

RedVent. Turned off ventilation at night in schools - risks and opportunities; RedVent. Avstaengd ventilation paa natten i skolor - risker och moejligheter

Energy Technology Data Exchange (ETDEWEB)

Haegerhed Engman, Linda; Fyhr, Kristina; Langer, Sarka; Ruud, Svein; Ylmen, Peter

2011-07-01

Reduced ventilation rates or shutdown ventilation during nights is often being used in school buildings in order to save energy and can decrease the energy cost for heating and ventilation with at least 30 %. Swedish Building Regulations (BBR) allows reduced ventilation flow in non-residential buildings when no one is using the building but it must not give rise to adverse health effects or damage the building or its installations. Potential risks are mould- and moisture damages and indoor air quality problems. Another question is whether the shut down itself might lead to indoor air quality problems due to chemical reactions between outdoor air and indoor emissions built-up during the night. The study was divided into three steps; an interview with property managers and care-taker, calculations of energy saving potentials and a field study. Measurements were per-formed in one classroom for two weeks in April 2010. Different set-ups for ventilation flow during night time and air tightness of the building envelope were studied; ventilation shut down, intermittent ventilation (15 min every second hour) and continuous full speed ventilation during night. In the studied classroom, shutdown ventilation during nights did not significantly affect the indoor air quality in the classroom during the school day even though there were effects seen during the night. We found a somewhat higher moisture accumulation those nights when the ventilation was shut down and some fractions of particles during intermittent ventilation compared to continues full ventilation during night time. This specific school and classroom were well ventilated and there was no moisture supply from new building material or other types of moisture producing activities. Schools with lower day-time ventilation rates, moisture in building construction, IAQ- or dampness problems as well as buildings close to heavy traffic should analyse the conditions for the specific building before reducing ventilation to

Ventilation Effectiveness

DEFF Research Database (Denmark)

Mundt, M.; Mathisen, H. M.; Moser, M.

Improving the ventilation effectiveness allows the indoor air quality to be significantly enhanced without the need for higher air changes in the building, thereby avoiding the higher costs and energy consumption associated with increasing the ventilation rates. This Guidebook provides easy-to-un...

The role of ventilation. 2 v. Proceedings

International Nuclear Information System (INIS)

1994-01-01

The 78 papers which constitute the proceedings of the conference are presented in two volumes. The papers in the first volume cover sessions dealing with the following broad topics: ventilation strategies; indoor air quality; energy impact of ventilation; building design for optimum ventilation; ventilation and energy. Volume 2 also covers ventilation strategies and ventilation and energy, and in addition: calculation, measurement and design tools; measurement and modelling. Separate abstract have been prepared for 4 papers in Volume 1 which deal with the role of ventilation in mitigating the hazard of radon in buildings. (UK)

Ventilation Positive Pressure Intervention Effect on Indoor Air Quality in a School Building with Moisture Problems

Directory of Open Access Journals (Sweden)

Camilla Vornanen-Winqvist

2018-01-01

Full Text Available This case study investigates the effects of ventilation intervention on measured and perceived indoor air quality (IAQ in a repaired school where occupants reported IAQ problems. Occupants’ symptoms were suspected to be related to the impurities leaked indoors through the building envelope. The study’s aim was to determine whether a positive pressure of 5–7 Pa prevents the infiltration of harmful chemical and microbiological agents from structures, thus decreasing symptoms and discomfort. Ventilation intervention was conducted in a building section comprising 12 classrooms and was completed with IAQ measurements and occupants’ questionnaires. After intervention, the concentration of total volatile organic compounds (TVOC and fine particulate matter (PM2.5 decreased, and occupants’ negative perceptions became more moderate compared to those for other parts of the building. The indoor mycobiota differed in species composition from the outdoor mycobiota, and changed remarkably with the intervention, indicating that some species may have emanated from an indoor source before the intervention.

Ventilation Positive Pressure Intervention Effect on Indoor Air Quality in a School Building with Moisture Problems

Science.gov (United States)

Vornanen-Winqvist, Camilla; Järvi, Kati; Toomla, Sander; Ahmed, Kaiser; Andersson, Maria A.; Mikkola, Raimo; Marik, Tamás; Salonen, Heidi

2018-01-01

This case study investigates the effects of ventilation intervention on measured and perceived indoor air quality (IAQ) in a repaired school where occupants reported IAQ problems. Occupants’ symptoms were suspected to be related to the impurities leaked indoors through the building envelope. The study’s aim was to determine whether a positive pressure of 5–7 Pa prevents the infiltration of harmful chemical and microbiological agents from structures, thus decreasing symptoms and discomfort. Ventilation intervention was conducted in a building section comprising 12 classrooms and was completed with IAQ measurements and occupants’ questionnaires. After intervention, the concentration of total volatile organic compounds (TVOC) and fine particulate matter (PM2.5) decreased, and occupants’ negative perceptions became more moderate compared to those for other parts of the building. The indoor mycobiota differed in species composition from the outdoor mycobiota, and changed remarkably with the intervention, indicating that some species may have emanated from an indoor source before the intervention. PMID:29385772

Ventilation Positive Pressure Intervention Effect on Indoor Air Quality in a School Building with Moisture Problems.

Science.gov (United States)

Vornanen-Winqvist, Camilla; Järvi, Kati; Toomla, Sander; Ahmed, Kaiser; Andersson, Maria A; Mikkola, Raimo; Marik, Tamás; Kredics, László; Salonen, Heidi; Kurnitski, Jarek

2018-01-30

This case study investigates the effects of ventilation intervention on measured and perceived indoor air quality (IAQ) in a repaired school where occupants reported IAQ problems. Occupants' symptoms were suspected to be related to the impurities leaked indoors through the building envelope. The study's aim was to determine whether a positive pressure of 5-7 Pa prevents the infiltration of harmful chemical and microbiological agents from structures, thus decreasing symptoms and discomfort. Ventilation intervention was conducted in a building section comprising 12 classrooms and was completed with IAQ measurements and occupants' questionnaires. After intervention, the concentration of total volatile organic compounds (TVOC) and fine particulate matter (PM 2.5 ) decreased, and occupants' negative perceptions became more moderate compared to those for other parts of the building. The indoor mycobiota differed in species composition from the outdoor mycobiota, and changed remarkably with the intervention, indicating that some species may have emanated from an indoor source before the intervention.

Modelica Library for Building Heating, Ventilation and Air-Conditioning Systems

Energy Technology Data Exchange (ETDEWEB)

Wetter, Michael

2009-06-17

This paper presents a freely available Modelica library for building heating, ventilation and air conditioning systems. The library is based on the Modelica.Fluid library. It has been developed to support research and development of integrated building energy and control systems. The primary applications are controls design, energy analysis and model-based operation. The library contains dynamic and steady-state component models that are applicable for analyzing fast transients when designing control algorithms and for conducting annual simulations when assessing energy performance. For most models, dimensional analysis is used to compute the performance for operating points that differ from nominal conditions. This allows parameterizing models in the absence of detailed geometrical information which is often impractical to obtain during the conceptual design phase of building systems. In the first part of this paper, the library architecture and the main classes are described. In the second part, an example is presented in which we implemented a model of a hydronic heating system with thermostatic radiator valves and thermal energy storage.

Influence of input data on airflow network accuracy in residential buildings with natural wind- and stack-driven ventilation

Institute of Scientific and Technical Information of China (English)

Krzysztof Arendt; Marek Krzaczek; Jacek Tejchman

2017-01-01

The airflow network (AFN) modeling approach provides an attractive balance between the accuracy and computational demand for naturally ventilated buildings. Its accuracy depends on input parameters such as wind pressure and opening discharge coefficients. In most cases, these parameters are obtained from secondary sources which are solely representative for very simplified buildings, i.e. for buildings without facade details. Although studies comparing wind pressure coefficients or discharge coefficients from different sources exist, the knowledge regarding the effect of input data on AFN is still poor. In this paper, the influence of wind pressure data on the accuracy of a coupled AFN-BES model for a real building with natural wind- and stack-driven ventilation was analyzed. The results of 8 computation cases with different wind pressure data from secondary sources were compared with the measured data. Both the indoor temperatures and the airflow were taken into account. The outcomes indicated that the source of wind pressure data had a significant influence on the model performance.

Improving building energy efficiency in India: State-level analysis of building energy efficiency policies

Energy Technology Data Exchange (ETDEWEB)

Yu, Sha; Tan, Qing; Evans, Meredydd; Kyle, Page; Vu, Linh; Patel, Pralit L.

2017-11-01

India is expected to add 40 billion m2 of new buildings till 2050. Buildings are responsible for one third of India’s total energy consumption today and building energy use is expected to continue growing driven by rapid income and population growth. The implementation of the Energy Conservation Building Code (ECBC) is one of the measures to improve building energy efficiency. Using the Global Change Assessment Model, this study assesses growth in the buildings sector and impacts of building energy policies in Gujarat, which would help the state adopt ECBC and expand building energy efficiency programs. Without building energy policies, building energy use in Gujarat would grow by 15 times in commercial buildings and 4 times in urban residential buildings between 2010 and 2050. ECBC improves energy efficiency in commercial buildings and could reduce building electricity use in Gujarat by 20% in 2050, compared to the no policy scenario. Having energy codes for both commercial and residential buildings could result in additional 10% savings in electricity use. To achieve these intended savings, it is critical to build capacity and institution for robust code implementation.

Numerical investigations of buoyancy-driven natural ventilation in a simple atrium building and its effect on the thermal comfort conditions

International Nuclear Information System (INIS)

Hussain, Shafqat; Oosthuizen, Patrick H.

2012-01-01

In the present study use of solar-assisted buoyancy-driven natural ventilation in a simple atrium building is explored numerically with particular emphasis on the thermal comfort conditions in the building. Initially various geometric configurations of the atrium space were considered in order to investigate airflows and temperature distributions in the building using a validated computational fluid dynamics (CFD) model. The Reynolds Averaged Navier–Stokes (RANS) modelling approach with the SST-k–ω turbulence model and the Discrete Transfer Radiation Model (DTRM) was used for the investigations. The steady-state governing equations were solved using a commercial CFD solver FLUENT © . From the numerical results obtained, it was noted that an atrium space integrated with a solar chimney would be a relatively better option to be used in an atrium building. In the geometry selected, the performance of the building in response to various changes in design parameters was investigated. The produced airflows and temperature distributions were then used to evaluate indoor thermal comfort conditions in terms of the thermal comfort indices, i.e. the well-known predicted mean vote (PMV) index, its modifications especially for natural ventilation, predicted percent dissatisfied (PPD) index and Percent dissatisfied (PD) factor due to draft. It was found that the thermal conditions in the occupied areas of the building developed as a result of the use of solar-assisted buoyancy-driven ventilation for the particular values of the design parameters selected are mostly in the comfortable zone. Finally, it is demonstrated that the proposed methodology leads to reliable thermal comfort predictions, while the effect of various design variables on the performance of the building is easily recognized. - Highlights: ► Numerical investigations were carried for the use of buoyancy-driven displacement ventilation in a simple atrium building. ► Effect of various atrium

Design Principles for Hybrid Ventilation

DEFF Research Database (Denmark)

Heiselberg, Per

For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system -Hybrid Ventilation. ....... The hybrid ventilation concepts, design challenges and - principles are discussed and illustrated by four building examples....

A MODEL BUILDING CODE ARTICLE ON FALLOUT SHELTERS WITH RECOMMENDATIONS FOR INCLUSION OF REQUIREMENTS FOR FALLOUT SHELTER CONSTRUCTION IN FOUR NATIONAL MODEL BUILDING CODES.

Science.gov (United States)

American Inst. of Architects, Washington, DC.

A MODEL BUILDING CODE FOR FALLOUT SHELTERS WAS DRAWN UP FOR INCLUSION IN FOUR NATIONAL MODEL BUILDING CODES. DISCUSSION IS GIVEN OF FALLOUT SHELTERS WITH RESPECT TO--(1) NUCLEAR RADIATION, (2) NATIONAL POLICIES, AND (3) COMMUNITY PLANNING. FALLOUT SHELTER REQUIREMENTS FOR SHIELDING, SPACE, VENTILATION, CONSTRUCTION, AND SERVICES SUCH AS ELECTRICAL…

Validating computational predictions of night-time ventilation in Stanford's Y2E2 building

Science.gov (United States)

Chen, Chen; Lamberti, Giacomo; Gorle, Catherine

2017-11-01

Natural ventilation can significantly reduce building energy consumption, but robust design is a challenging task. We previously presented predictions of natural ventilation performance in Stanford's Y2E2 building using two models with different levels of fidelity, embedded in an uncertainty quantification framework to identify the dominant uncertain parameters and predict quantified confidence intervals. The results showed a slightly high cooling rate for the volume-averaged temperature, and the initial thermal mass temperature and window discharge coefficients were found to have an important influence on the results. To further investigate the potential role of these parameters on the observed discrepancies, the current study is performing additional measurements in the Y2E2 building. Wall temperatures are recorded throughout the nightflush using thermocouples; flow rates through windows are measured using hotwires; and spatial variability in the air temperature is explored. The measured wall temperatures are found the be within the range of our model assumptions, and the measured velocities agree reasonably well with our CFD predications. Considerable local variations in the indoor air temperature have been recorded, largely explaining the discrepancies in our earlier validation study. Future work will therefore focus on a local validation of the CFD results with the measurements. Center for Integrated Facility Engineering (CIFE).

Optimization of air-curtain sealing efficiency with respect to heat transfer in naturally ventilated buildings

NARCIS (Netherlands)

Khayrullina, A.; Hooff, van T.A.J.; Blocken, B.J.E.; van Heijst, G.J.F.; Sun, Y.; Pei, J.; Zhao, X

This study presents results of coupled 3D steady Reynolds-averaged Navier-Stokes (RANS) Computational Fluid Dynamics (CFD) simulations of an isolated naturally-ventilated building with the application of an air curtain to prevent heat transfer across a doorway. The considered parameters include air

Preventing chronic lung disease in an aging society by improved building ventilation : An economic assessment

NARCIS (Netherlands)

Franchimon, F.; Ament, A.H.J.A.; Pernot, C.E.E.; Knies, J.; Bronswijk, van J.E.M.H.

2008-01-01

Leading edge ventilation systems in buildings might slow down the degradation of quality of life in a population. We therefore performed an economic assessment to determine the Incremental Cost-Effectiveness Ratio (the amount of money needed to produce one healthy life year) for a full-scale

Survey execution to build a ventilation model, Australian style

Energy Technology Data Exchange (ETDEWEB)

Rowland, J.A. [Dallas Mining Services Pty Ltd., Wollongong, NSW (Australia)

2010-07-01

Ventilation surveys and the development of a properly tuned ventilation model are important components of a modern underground mine safety management system to ensure the safety of miners. Such systems in Australia revolve around the routine application of risk based logic. However, assessing the risk in ventilation systems always changes. Designers of ventilation circuits therefore use ventilation modeling software as a key tool to facilitate the structured process. This paper emphasized the importance of measuring the underground circuit and replicating the measurements in a working model. The most commonly used modeling program in Australia is the Ventsim software which is available as a fully graphical 3D configuration as well as a 2D version. The value of the mine ventilation survey lies in the ability of the data to be accurately replicated on a mine ventilation model. As such, much thought must be given to the ventilation survey scope of work and overall process. The surveys must satisfy operational needs and must delineate the circuit to a level that will allow a model be to accurately assembled in order to determine when minor or major ventilation circuit adjustments are needed. 1 ref., 10 figs.

Contribution to the study of hybrid ventilation system effectiveness in office and educational buildings; Contribution a l'etude de l'efficacite des systemes de ventilation hybride dans les batiments du secteur tertiaire

Energy Technology Data Exchange (ETDEWEB)

Cron, F.

2004-06-15

This study is part of the International Energy Agency Annex 35, 'Hybrid Ventilation in New and Retro-fitted Office Buildings', also called the HybVent Project. It presents the numerical analyses of a number of hybrid ventilation systems and their potential for several buildings in relation to local climate characteristics. The first part of this work reviews the state-of-the-art of existing ventilation systems and details the principles, expectations and features of hybrid ventilation systems. This first section also examines some examples of hybrid systems extracted from the collection of Annex 35 case studies. A comprehensive bibliography of numerical tools available for this type of analysis is given in the second section. The numerical models for building simulation and the object-oriented environment used to develop our simulation tool are presented in this section as well. Two single-zone studies undertaken in this project are reported in the third section. The first study concerns an experimental cell simulation. Numerical results are compared to experimental data to validate the use of the simulation tool developed. The second single-zone study predicts the potential of a specific hybrid ventilation system in a typical classroom, given climatic conditions. Finally, the last section presents a more complete study - a multi-zone study of the Tonga school, an Annex 35 case study located in Sweden. Three rooms were modelled initially to compare numerical results to experimental data and then to analyse the performance of the existing hybrid ventilation system and two other systems. This final study was completed for three European cities with very different climates. The overall analysis of the potential of the hybrid ventilation systems considered and the perspective for future work are outlined in the conclusion. (author)

Lifecycle performance. Special issue on management and maintenance, hybrid ventilation concepts, installation-low buildings; Lifecycle performance. Themanummer over beheer en onderhoud, hybride ventilatieconcepten, installatie-arme gebouwen

Energy Technology Data Exchange (ETDEWEB)

Thierauf, I. [Universiteit Utrecht, Utrecht (Netherlands); Kurvers, S.R.; Van den Ham, E.R.; Leijten, J.L. [Sectie Climate Design and Sustainability, Afdeling Architectural Engineering and Technology, Faculteit Bouwkunde, Technische Universiteit Delft TUD, Delft (Netherlands); Juricic, S. [Ecole National des Travaux Publics de l' Etat, Lyon (France); Jacobs, P. [Afdeling Energy and Comfort Systems, TNO, Delft (Netherlands); Versteeg, H. [LBP Sight, Nieuwegein (Netherlands); Van Loon, P.P.M. [Stichting Scholen van Morgen, Rotterdam (Netherlands); Hoek, H.C.; Van Eeden, H.; Nibbelink, J. [Collectief C-on, Haarlem (Netherlands); Veerman, J.; Maassen, W.H. [Royal Haskoning DHV, Nijmegen (Netherlands); Derksen, A.H.P. [ISSO, Rotterdam (Netherlands); Morren, K. [Universiteit Twente, Enschede (Netherlands)

2012-12-15

In 9 articles various aspects regarding the title topic are discussed: energy efficiency and user comfort, ventilation in new houses with balanced ventilation, the revised assessment for ventilation performance, air quality in school buildings, buildings with only a few installations, hybrid ventilation, the management and maintenance process, and future performance requirements [Dutch] In 9 artikelen wordt aandacht besteed aan diverse aspecten m.b.t. het titelonderwerp: energie-efficientie en gebruikerscomfort, ventilatie in nieuwbouwwoningen met balansventilatie, de herziene beoordelingsrichtlijn ventilatie prestatie, luchtkwaliteit in schoolgebouwen, installatie-arme gebouwen, hybride ventilatie, het beheer- en onderhoudsproces, en de toekomstige prestatie-eisen.

Building envelope design for renewal of air by natural ventilation in moderate climates. Proposition of a designing methodology; Conception des enveloppes de batiments pour le renouvellement d'air par ventilation naturelle en climats temperes. Proposition d'une methodologie de conception

Energy Technology Data Exchange (ETDEWEB)

Mansouri, Y.

2003-12-01

The subject of this research is to produce methods and methodological tools for the architects to support the integration of natural ventilation systems in the building envelope design. Our research is situated to the interface between the architectural practice and the physical research on natural ventilation. We are interested in phenomena that can influence or force the strategy of ventilation. A morphological analysis of naturally ventilated buildings concerning the integration modes of natural ventilation systems is done permitting US to propose a typology and a topology of ventilation systems. We define criteria in relation to the thermal comfort, to the quality of air and the economy of energy to assess air renewal techniques. In complement of the sizing tool, we elaborate a methodology of conception for the integration of passives ventilation systems. Design guidelines permit US to conclude on an effective natural ventilation system which is well adapted to collective habitat. (author)

The correlation of Acanthamoeba from the ventilation system with other environmental parameters in commercial buildings as possible indicator for indoor air quality.

Science.gov (United States)

Ooi, Soo Shen; Mak, Joon Wah; Chen, Donald K F; Ambu, Stephen

2017-02-07

The free-living protozoan Acanthamoeba is an opportunistic pathogen that is ubiquitous in our environment. However, its role in affecting indoor air quality and ill-health of indoor occupants is relatively unknown. The present study investigated the presence of Acanthamoeba from the ventilation system and its correlation with other indoor air quality parameters, used in the industry code of practice and its potential as an indicator for indoor air quality. Indoor air quality assessments were carried out in nine commercial buildings with approval from the building management, and the parameters assessed were as recommended by the Department of Occupational Safety and Health. The presence of Acanthamoeba was determined through dust swabs from the ventilation system and indoor furniture. Logistic regression was performed to study the correlation between assessed parameters and occupants' complaints. A total of 107 sampling points were assessed and 40.2% of the supplying air diffuser and blowing fan and 15% of the furniture were positive for cysts. There was a significant correlation between Acanthamoeba detected from the ventilation system with ambient total fungus count (r=0.327; p=0.01) and respirable particulates (r=0.276; p=0.01). Occupants' sick building syndrome experience also correlated with the presence of Acanthamoeba in the ventilation system (r=0.361; p=0.01) and those detected on the furniture (r=0.290; p=0.01). Logistic regression showed that there was a five-fold probability of sick building syndrome among occupants when Acanthamoeba was detected in the ventilation system.

A simplified model for estimating population-scale energy impacts of building envelope air-tightening and mechanical ventilation retrofits

Energy Technology Data Exchange (ETDEWEB)

Logue, Jennifer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Turner, William J. N. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Trinity College Dublin, Dublin (Ireland); Walker, Iain S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, Brett C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2015-01-19

Changing the air exchange rate of a home (the sum of the infiltration and mechanical ventilation airflow rates) affects the annual thermal conditioning energy. Large-scale changes to air exchange rates of the housing stock can significantly alter the residential sector's energy consumption. However, the complexity of existing residential energy models is a barrier to the accurate quantification of the impact of policy changes on a state or national level. The Incremental Ventilation Energy (IVE) model developed in this study combines the output of simple air exchange models with a limited set of housing characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modellers to use existing databases of housing characteristics to determine the impact of ventilation policy change on a population scale. The IVE model estimates of energy change when applied to US homes with limited parameterisation are shown to be comparable to the estimates of a well-validated, complex residential energy model.

Hybrid Ventilation Air Flow Process

DEFF Research Database (Denmark)

Heiselberg, Per Kvols

The scope of this annex is therefore to obtain better knowledge of the use of hybrid ventilation technologies. The annex focus on development of control strategies for hybrid ventilation, on development of methods to predict hybrid ventilation performance in office buildings and on implementation...

CLASSIFICATION OF THE MGR WASTE HANDLING BUILDING VENTILATION SYSTEM

International Nuclear Information System (INIS)

J.A. Ziegler

2000-01-01

The purpose of this analysis is to document the Quality Assurance (QA) classification of the Monitored Geologic Repository (MGR) waste handling building ventilation system structures, systems and components (SSCs) performed by the MGR Preclosure Safety and Systems Engineering Section. This analysis also provides the basis for revision of YMP/90-55Q, Q-List (YMP 2000). The Q-List identifies those MGR SSCs subject to the requirements of DOE/RW-0333P, ''Quality Assurance Requirements and Description'' (QARD) (DOE 2000). This QA classification incorporates the current MGR design and the results of the ''Design Basis Event Frequency and Dose Calculation for Site Recommendation'' (CRWMS M andO 2000a) and ''Bounding Individual Category 1 Design Basis Event Dose Calculation to Support Quality Assurance Classification'' (Gwyn 2000)

Barriers' and policies' analysis of China's building energy efficiency

International Nuclear Information System (INIS)

Zhang, Yurong; Wang, Yuanfeng

2013-01-01

With the rapid economic growth and the improvement of people's living standards, China's building energy consumption has kept rising during the past 15 years. Under the effort of the Chinese government and the society, China's building energy efficiency has made certain achievements. However, the implementation of building energy efficiency in China is still far from its potential. Based on the analysis of the existing policies implemented in China, the article concluded that the most essential and the most effective ways to promote building energy efficiency is the government's involvement as well as economic and financial incentives. In addition, the main barriers in the process of promoting building energy efficiency in China are identified in six aspects. It has been found that the legal system and administrative issues constitute major barriers, and the lack of financial incentives and the mismatching of market mechanism also hamper the promotion of building energy efficiency. Finally, in view of the existing policies and barriers analysis, three corresponding policy proposals are presented. -- Highlights: •The existing policies implemented in China from three aspects are presented and analysed. •The Government's involvement is the most essential effective way to promote building-energy efficiency. •Six aspects of barriers in promoting building energy efficiency in China are identified. •The legal system and administrative issues constitute the major barriers. •Three policy proposals to further promote building energy efficiency in China are proposed

Design and operation of ventilation in low energy residences – A survey on code requirements and building reality from six European countries and China

DEFF Research Database (Denmark)

del Carmen Bocanegra-Yanez, Maria; Rojas, Gabriel; Zukowska-Tejsen, Daria

involved in the Annex. There were two main objectives, firstly, to describe and analyse a transition between actual requirements (national building codes and standards) and current practice. Secondly, to investigate current barriers and challenges regarding installation of mechanical ventilation......One of the key objectives of the IEA Annex 68 research programme entitled “Indoor Air Quality Design and Control in Low Energy Residential Buildings” is to provide a generic guideline for the design and operation of ventilation in residential buildings. Modern and refurnished domestic buildings...

Short-term airing by natural ventilation

DEFF Research Database (Denmark)

Perino, Marco; Heiselberg, Per

2009-01-01

The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. This kind of system frequently integrates traditio......The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. This kind of system frequently integrates...... traditional mechanical ventilation components with natural ventilation devices, such as motorized windows and louvers. Among the various ventilation strategies that are currently available, buoyancy driven single-sided natural ventilation has proved to be very effective and can provide high air change rates...... that was aimed at developing and validating numerical models for the analysis of buoyancy driven single-sided natural ventilation systems. Once validated, these models can be used to optimize control strategies in order to achieve satisfactory indoor comfort conditions and IAQ....

Decommissioning of Active Ventilation Systems in a Nuclear R and D Facility to Prepare for Building Demolition (Whiteshell Laboratories Decommissioning Project, Canada) - 13073

International Nuclear Information System (INIS)

Wilcox, Brian; May, Doug; Howlett, Don; Bilinsky, Dennis

2013-01-01

Whiteshell Laboratories (WL) is a nuclear research establishment owned by the Canadian government and operated by Atomic Energy of Canada Limited (AECL) since the early 1960's. WL is currently under a decommissioning license and the mandate is to remediate the nuclear legacy liabilities in a safe and cost effective manner. The WL Project is the first major nuclear decommissioning project in Canada. A major initiative underway is to decommission and demolish the main R and D Laboratory complex. The Building 300 R and D complex was constructed to accommodate laboratories and offices which were mainly used for research and development associated with organic-cooled reactors, nuclear fuel waste management, reactor safety, advanced fuel cycles and other applications of nuclear energy. Building 300 is a three storey structure of approximately 16,000 m 2 . In order to proceed with building demolition, the contaminated systems inside the building have to be characterized, removed, and the waste managed. There is a significant focus on volume reduction of radioactive waste for the WL project. The active ventilation system is one of the significant contaminated systems in Building 300 that requires decommissioning and removal. The active ventilation system was designed to manage hazardous fumes and radioactivity from ventilation devices (e.g., fume hoods, snorkels and glove boxes) and to prevent the escape of airborne hazardous material outside of the laboratory boundary in the event of an upset condition. The system includes over 200 ventilation devices and 32 active exhaust fan units and high efficiency particulate air (HEPA) filters. The strategy to remove the ventilation system was to work from the laboratory end back to the fan/filter system. Each ventilation duct was radiologically characterized. Fogging was used to minimize loose contamination. Sections of the duct were removed by various cutting methods and bagged for temporary storage prior to disposition

How to Plan Ventilation Systems.

Science.gov (United States)

Clarke, John H.

1963-01-01

Ventilation systems for factory safety demand careful planning. The increased heat loads and new processes of industry have introduced complex ventilation problems in--(1) ventilation supply, (2) duct work design, (3) space requirements, (4) hood face velocities, (5) discharge stacks, and (6) building eddies. This article describes and diagrams…

The influence of opening windows and doors on the natural ventilation rate of a residential building

Science.gov (United States)

An analysis of air exchange rates due to intentional window and door openings in a research test house located in a residential environment is presented. These data inform the development of ventilation rate control strategies as building envelopes are tightened to improve the e...

Occupant Time Period of Thermal Adaption to Change of Outdoor Air Temperature in Naturally Ventilated Buildings

DEFF Research Database (Denmark)

liu, weiwei; Wargocki, Pawel; Xiong, Jing

2014-01-01

The present work proposed a method to determine time period of thermal adaption of occupants in naturally ventilated building, based on the relationship between their neutral temperatures and running mean outdoor air temperature. Based on the data of the field investigation, the subjects’ time...

Application of fuzzy control in naturally ventilated buildings for summer conditions

Energy Technology Data Exchange (ETDEWEB)

Eftekhari, M.M. [Loughborough University (United Kingdom). Department of Civil and Building Engineering; Marjanovic, L.D. [University of Belgrade (Yugoslavia). Faculty of Mechanical Engineering

2003-08-01

The objective of this work is to develop a fuzzy controller for naturally ventilated buildings. Approximate reasoning has proven to be in many cases more successful control strategy than classically designed controlled scheme. In this paper the process of designing a supervisory control to provide thermal comfort and adequate air distribution inside a single-sided naturally ventilated test room is described. The controller is based on fuzzy logic reasoning and sets of linguistic rules in forms of IF-THEN rules are used. The inputs to the controller are the outside wind velocity, direction, outside and inside temperatures. The output is the position of the opening. A selection of membership functions for input and output variables are described and analysed. The control strategy consisting of the expert rules is then validated using experimental data from a naturally ventilated test room. The test room is located in a sheltered area and air flow inside the room, the air pressures and velocities across the openings together with indoor air temperature and velocity at four locations and six different levels were measured. Validation of the controller is performed in the test room by measuring the air distribution and thermal comfort inside the room with no control action. These data are then compared to the air temperature and velocity with the controller in action. The initial results are presented here, which shows that the controller is capable of providing better thermal comfort inside the room. (author)

Why this crisis in residential ventilation

NARCIS (Netherlands)

Hasselaar, E.

2008-01-01

Ventilation is the cornerstone of good indoor air quality. Ventilation requirements have major attention in building regulations, but ventilation in practice is often poor, resulting in increased concentration of pollutants and hence exposure to health risk. Inspection of 500 houses with interviews

Simultaneousness of room heating and ventilation air heating

International Nuclear Information System (INIS)

Mathisen, Hans Martin

2006-01-01

The report is part of NTNU-SINTEF's Smart Buildings program, Smart Energy Efficient Buildings (2002-2006), subprogram 3.1 Heating, ventilation and cooling systems. An important part of this subprogram is the development and implementation of heating distribution systems with low return temperature. A comparison has been made of the simultaneousness of room heating and ventilation air heating in six buildings. Existing measuring data with hourly measurements of effect requirements for the different purposes have been employed. Based on the measuring data the relation between the requirements for room heating and ventilation is estimated. A 'fictitious' return temperature has also been estimated. The result shows a significant variation between the buildings. For all there are short periods where the efficiency need for room heating and ventilation is equal (ml)

Adaptive neuro-fuzzy inference systems (ANFIS) application to investigate potential use of natural ventilation in new building designs in Turkey

Energy Technology Data Exchange (ETDEWEB)

Ayata, Tahir; Cam, Ertugrul; Yildiz, Osman [Kirikkale University, Faculty of Engineering, 71451, Campus, Kirikkale (Turkey)

2007-05-15

Natural ventilation in living and working places provides both circulation of clear air and a decrease of indoor temperature, especially during hot summer days. In addition to openings, the dimension ratio and position of buildings play a significant role to obtain a uniform indoor air velocity distribution. In this study, the potential use of natural ventilation as a passive cooling system in new building designs in Kayseri, a midsize city in Turkey, was investigated. First, indoor air velocity distributions with respect to changing wind direction and magnitude were simulated by the FLUENT package program, which employs finite element methods. Then, an adaptive neuro-fuzzy inference systems (ANFIS) model was employed to predict indoor average and maximum air velocities using the simulated data by FLUENT. The simulation results suggest that natural ventilation can be used to provide a thermally comfortable indoor environment during the summer season in the study area. Also, the ANFIS model can be proposed for estimation of indoor air velocity values in such studies. (author)

Sensor-based demand controlled ventilation

Energy Technology Data Exchange (ETDEWEB)

De Almeida, A.T. [Universidade de Coimbra (Portugal). Dep. Eng. Electrotecnica; Fisk, W.J. [Lawrence Berkeley National Lab., CA (United States)

1997-07-01

In most buildings, occupancy and indoor pollutant emission rates vary with time. With sensor-based demand-controlled ventilation (SBDCV), the rate of ventilation (i.e., rate of outside air supply) also varies with time to compensate for the changes in pollutant generation. In other words, SBDCV involves the application of sensing, feedback and control to modulate ventilation. Compared to ventilation without feedback, SBDCV offers two potential advantages: (1) better control of indoor pollutant concentrations; and (2) lower energy use and peak energy demand. SBDCV has the potential to improve indoor air quality by increasing the rate of ventilation when indoor pollutant generation rates are high and occupants are present. SBDCV can also save energy by decreasing the rate of ventilation when indoor pollutant generation rates are low or occupants are absent. After providing background information on indoor air quality and ventilation, this report provides a relatively comprehensive discussion of SBDCV. Topics covered in the report include basic principles of SBDCV, sensor technologies, technologies for controlling air flow rates, case studies of SBDCV, application of SBDCV to laboratory buildings, and research needs. SBDCV appears to be an increasingly attractive technology option. Based on the review of literature and theoretical considerations, the application of SBDCV has the potential to be cost-effective in applications with the following characteristics: (a) a single or small number of dominant pollutants, so that ventilation sufficient to control the concentration of the dominant pollutants provides effective control of all other pollutants; (b) large buildings or rooms with unpredictable temporally variable occupancy or pollutant emission; and (c) climates with high heating or cooling loads or locations with expensive energy.

Functionality of Ventilated Facades: Protection of Insulation

Directory of Open Access Journals (Sweden)

Petrichenko Mikhail

2016-01-01

Full Text Available This article discusses about methods of construction of the ventilated facades. The ventilated facade is not only the element of facing, it is the supporting structure. Their main objective - creation of air ventilating space between a facade and an external wall of the building. Moving of air in this gap protects a heater from destruction, interfering with a moisture congestion. In addition, the ventilated facade protect the building from aggressive influence of external environment, have a sound and thermal insulation properties. There are several problems of systems of the ventilated facades connected with an application of a heater. For more effective using it is necessary to minimize contact of a heater with environment.

Energy Efficiency Requirements in Building Codes, Energy Efficiency Policies for New Buildings. IEA Information Paper

Energy Technology Data Exchange (ETDEWEB)

Laustsen, Jens

2008-03-15

The aim of this paper is to describe and analyse current approaches to encourage energy efficiency in building codes for new buildings. Based on this analysis the paper enumerates policy recommendations for enhancing how energy efficiency is addressed in building codes and other policies for new buildings. This paper forms part of the IEA work for the G8 Gleneagles Plan of Action. These recommendations reflect the study of different policy options for increasing energy efficiency in new buildings and examination of other energy efficiency requirements in standards or building codes, such as energy efficiency requirements by major renovation or refurbishment. In many countries, energy efficiency of buildings falls under the jurisdiction of the federal states. Different standards cover different regions or climatic conditions and different types of buildings, such as residential or simple buildings, commercial buildings and more complicated high-rise buildings. There are many different building codes in the world and the intention of this paper is not to cover all codes on each level in all countries. Instead, the paper details different regions of the world and different ways of standards. In this paper we also evaluate good practices based on local traditions. This project does not seek to identify one best practice amongst the building codes and standards. Instead, different types of codes and different parts of the regulation have been illustrated together with examples on how they have been successfully addressed. To complement this discussion of efficiency standards, this study illustrates how energy efficiency can be improved through such initiatives as efficiency labelling or certification, very best practice buildings with extremely low- or no-energy consumption and other policies to raise buildings' energy efficiency beyond minimum requirements. When referring to the energy saving potentials for buildings, this study uses the analysis of recent IEA

Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

Energy Technology Data Exchange (ETDEWEB)

Martin, Eric [Building Science Corporation, Westford, MA (United States)

2014-01-01

Optimizing whole house mechanical ventilation as part of the Building Ameerica program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this report is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

Building occupancy diversity and HVAC (heating, ventilation, and air conditioning) system energy efficiency

International Nuclear Information System (INIS)

Yang, Zheng; Ghahramani, Ali; Becerik-Gerber, Burcin

2016-01-01

Approximately forty percent of total building energy consumption is attributed to HVAC (heating, ventilation, and air conditioning) systems that aim to maintain healthy and comfortable indoor environments. An HVAC system is a network with several subsystems, and there exist heat transfer and balance among the zones of a building, as well as heat gains and losses through a building's envelope. Diverse occupancy (diversity in terms of when and how occupants occupy a building) in spaces could result in increase of loads that are not actual demands for an HVAC system, leading into inefficiencies. This paper introduces a framework to quantitatively evaluate the energy implications of occupancy diversity at the building level, where building information modeling is integrated to provide building geometries, HVAC system layouts, and spatial information as inputs for computing potential energy implications if occupancy diversity were to be eliminated. An agglomerate hierarchical clustering-based iterative evaluation algorithm is designed for iteratively eliminating occupancy diversity. Whole building energy simulations for a real-world building, as well as virtual reference buildings demonstrate that the proposed framework could effectively quantify the HVAC system energy efficiency affected by occupancy diversity and the framework is generalizable to different building geometries, layouts, and occupancy diversities. - Highlights: • Analyze relationships between occupancy diversity and HVAC energy efficiency. • Integrate BIM for quantifying energy implications of occupancy diversity. • Demonstrate the effectiveness and generalizability of iterative evaluation algorithm. • Improve agglomerative hierarchical clustering process using heap data structure.

Assessment of radon build up pattern in a closed room with minimal ventilation disturbance

International Nuclear Information System (INIS)

Singh, M.K.; Patnaik, R.L.; Jha, V.N.; Ravi, P.M.; Tripathi, R.M.

2016-01-01

Radon is ubiquitous in nature. The immediate source of Radon is 226 Ra is present in building materials underneath earth due to presence of natural uranium in terrestrial region. 222 Ra gas continuously diffused out into room atmosphere through the pores, cracks and fissures if any. The buildup of this 222 Rn is anticipated in a closed room lack of proper ventilation. A study was done to see the build up pattern of radon concentration by two different measurement techniques in a closed room of ESL, Jaduguda. Present paper summarizes the result of buildup study of 222 Rn in a closed room of lab for a period of 3 months

Natural Ventilation: A Mitigation Strategy to Reduce Overheating In Buildings under Urban Heat Island Effect in South American Cities

Science.gov (United States)

Palme, Massimo; Carrasco, Claudio; Ángel Gálvez, Miguel; Inostroza, Luis

2017-10-01

Urban heat island effect often produces an increase of overheating sensation inside of buildings. To evacuate this heat, the current use of air conditioning increases the energy consumption of buildings. As a good alternative, natural ventilation is one of the best strategies to obtain indoor comfort conditions, even in summer season, if buildings and urban designs are appropriated. In this work, the overheating risk of a small house is evaluated in four South American cities: Guayaquil, Lima, Antofagasta and Valparaíso, with and without considering the UHI effect. Then, natural ventilation is assessed in order to understand the capability of this passive strategy to assure comfort inside the house. Results show that an important portion of the indoor heat can be evacuated, however the temperature rising (especially during the night) due to UHI can generate a saturation effect if appropriate technical solutions, like the increase in the air speed that can be obtained with good urban design, are not considered.

Numerical analysis of the performance of a venturi-shaped roof for natural ventilation : influence of building width

NARCIS (Netherlands)

Hooff, van T.A.J.; Blocken, B.J.E.; Aanen, L.; Bronsema, B.

2012-01-01

A numerical analysis with Computational Fluid Dynamics (CFD) is performed to investigate the influence of building width on the performance of a venturi-shaped roof (called Ventec roof) for natural ventilation. The specific roof configuration is intended to create an underpressure in the narrowest

Ventilation-air conditioning system

International Nuclear Information System (INIS)

Kubokoya, Takashi.

1991-01-01

Heretofore, in ventilation-air conditioning systems in a nuclear power plant, exhaust gases from each of the ventilation-air conditioning systems of a reactor building, a turbine building, a waste processing building are joined and they are released into atmosphere from the top of a high main exhaustion stack. In order to build such a high main exhaustion stack, a considerable construction cost is required and, in addition, there is a worry of lacking balance with surrounding scenery. Then, in the present invention, exhaust gases are heated by waste heat in a turbine during their introduction from the ventilation-air conditioning facility in the building of a power plant to the main exhaust stack. With such a constitution, since the exhaust gases are heated and their temperature is elevated, they uprise by natural convection when they are released from the top of the main exhaustion stack to the atmosphere. Accordingly, they are released to a level higher than the conventional case in view of the volume of the blower which sends the exhaust gases under pressure, to diffuse them to the atmosphere more sufficiently compared with a conventional case. Further, the height of the main exhaustion stack can be reduced, enabling to minimize the cost for moving the blower. (T.M.)

Natural Ventilation of Buildings through Light Shafts. Design-Based Solution Proposals

Science.gov (United States)

Ángel Padilla-Marcos, Miguel; Meiss, Alberto; Feijó-Muñoz, Jesús

2017-10-01

This work analyses how the built environment affects the quality of the air to be introduced into buildings from light shafts. Several factors such as urban environment and building design intervene in the ability of the light shaft to produce its air change process. Urban areas continuously pollute the air in cities which affects the human health and the environment sustainability. Poor air quality outside buildings supposes a big energy waste to promote an acceptable air quality inside buildings. That requires a large flow rate to maintain the indoor air quality which is translated to an energy efficiency term. The main objective focuses on the impact of standardized architecture design in the quality of the indoor air dependent on the air change in the light shaft. The air change capacity of the outdoor space is numbered analysed using the concept of air change efficiency (ACE). ACE is determined by the built environment, the wind conditions and the design of the building containing light shafts. This concept is comparatively evaluated inside a control domain virtually defined to obtain the mean age of the air for a known air volume. The longer the light shaft in the wind direction is, the better the ACE is compared with other options. Light shafts up to 12 metres high are the most suitable in order to obtain acceptable efficiency results. Other studied cases verify that assumption. Different simplified tools for the technicians to evaluate the design of buildings containing light shafts are proposed. Some strategies of architectural design of buildings with light shafts to be used for ventilation are presented.

Design Principles for Natural and Hybrid Ventilation

OpenAIRE

Heiselberg, Per

2000-01-01

For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system- Hybrid Ventilation. The hybrid ventilation concepts, design challenges and principles are discussed and illustrated by four building examples.

Analysis of the systems of ventilation of residential houses of Ukraine and Estonia

Science.gov (United States)

Savchenko, Olena; Zhelykh, Vasyl; Voll, Hendrik

2017-12-01

The most common ventilation system in residential buildings in Ukraine is natural ventilation. In recent years, due to increased tightness of structures, an increase in the content of synthetic finishing materials in them, the quality of microclimate parameters deteriorated. One of the measures to improve the parameters of indoor air in residential buildings is the use of mechanical inflow and exhaust ventilation system. In this article the regulatory documents concerning the design of ventilation systems in Ukraine and Estonia and the requirements for air exchange in residential buildings are considered. It is established that the existing normative documents in Ukraine are analogous to European norms, which allow design the system of ventilation of residential buildings according to European standards. However, the basis for the design of ventilation systems in Ukraine is the national standards, in which mechanical ventilation, unfortunately, is provided only for the design of high-rise buildings. To maintain acceptable microclimate parameters in residential buildings, it is advisable for designers to apply the requirements for designing ventilation systems in accordance with European standards.

Analysis of the systems of ventilation of residential houses of Ukraine and Estonia

Directory of Open Access Journals (Sweden)

Savchenko Olena

2017-12-01

Full Text Available The most common ventilation system in residential buildings in Ukraine is natural ventilation. In recent years, due to increased tightness of structures, an increase in the content of synthetic finishing materials in them, the quality of microclimate parameters deteriorated. One of the measures to improve the parameters of indoor air in residential buildings is the use of mechanical inflow and exhaust ventilation system. In this article the regulatory documents concerning the design of ventilation systems in Ukraine and Estonia and the requirements for air exchange in residential buildings are considered. It is established that the existing normative documents in Ukraine are analogous to European norms, which allow design the system of ventilation of residential buildings according to European standards. However, the basis for the design of ventilation systems in Ukraine is the national standards, in which mechanical ventilation, unfortunately, is provided only for the design of high-rise buildings. To maintain acceptable microclimate parameters in residential buildings, it is advisable for designers to apply the requirements for designing ventilation systems in accordance with European standards.

Energy policy for integrating the building environmental performance model of an air conditioned building in a subtropical climate

International Nuclear Information System (INIS)

Mui, K.W.

2006-01-01

For an air conditioned building, the major electricity consumption is by the heating, and air conditioning (HVAC) system. As energy saving strategies may be in conflict with the criteria of indoor air quality and thermal comfort, a concept of the building environmental performance model (BEPM) has been developed to optimize energy consumption in HVAC systems without any deterioration of the indoor air quality and thermal comfort. The BEPM is divided into two main modules: the adaptive comfort temperature (ACT) module and the new demand control ventilation (nDCV) module. This study aims to enhance and prompt the conventional operation of the air side systems by incorporating temperature reset with the adaptive comfort temperature control and the new demand control ventilation system in high rise buildings in Hong Kong. A new example weather year (1991) was established as a reference to compute the energy use of HVAC systems in buildings in order to obtain more representative data for predicting annual energy consumption. A survey of 165 Hong Kong office buildings was conducted and it provided valuable information on the existing HVAC design values in different grades of private commercial buildings in Hong Kong. It was found that the actual measured values of indoor temperature were lower than the design ones. Furthermore, with the new example weather year and the integration of the BEPM into Grade A private office buildings in Hong Kong, the total energy saving of the air conditioning systems was calculated (i.e. a saving of HK$122 million in electrical consumption per year) while the thermal comfort for the occupants was also maintained

A First Approach to Natural Thermoventilation of Residential Buildings through Ventilation Chimneys Supplied by Solar Ponds

Directory of Open Access Journals (Sweden)

Ferdinando Salata

2015-07-01

Full Text Available The exploitation of natural ventilation is a good solution to improve buildings from an energetic point of view and to fulfill the requirements demanded by the thermohygrometric comfort and the air quality in enclosed spaces. Some past researches demonstrated how some devices, useful to this purpose, follow the principles of solar chimneys and are able to move air masses while exploiting the Archimedes thrust. The natural ventilation must be supplied by a flow moving upward, generated by a heat source performing at temperatures slightly higher than the one present in the environment. To have a minimum energetic effect, the heat can be extracted from solar ponds; solar ponds are able to collect and store solar energy in the geographical regions characterized by sufficient values of solar radiation. Thus it is possible, in summer, to provoke a nocturnal natural ventilation useful for the air change in indoor spaces (in those climatic areas where, during the night, there is a temperature gradient.

Computational fluid dynamics modelling of displacement natural ventilation.

OpenAIRE

Ji, Yingchun

2005-01-01

Natural ventilation is widely recognised as contributing towards low-energy building design. The requirement to reduce energy usage in new buildings has rejuvenated interest in natural ventilation. This thesis deals with computer modelling of natural displacement ventilation driven either by buoyancy or buoyancy combined with wind forces. Two benchmarks have been developed using computational fluid dynamics (CFD) in order to evaluate the accuracy with which CFD is able to mo...

Quantifying the impact of traffic-related air pollution on the indoor air quality of a naturally ventilated building.

Science.gov (United States)

Tong, Zheming; Chen, Yujiao; Malkawi, Ali; Adamkiewicz, Gary; Spengler, John D

2016-01-01

Improper natural ventilation practices may deteriorate indoor air quality when in close proximity to roadways, although the intention is often to reduce energy consumption. In this study, we employed a CFD-based air quality model to quantify the impact of traffic-related air pollution on the indoor air quality of a naturally ventilated building. Our study found that the building envelope restricts dispersion and dilution of particulate matter. The indoor concentration in the baseline condition located 10m away from the roadway is roughly 16-21% greater than that at the edge of the roadway. The indoor flow recirculation creates a well-mixed zone with little variation in fine particle concentration (i.e., 253nm). For ultrafine particles (building, particle size, wind condition, and window size and location. A break-even point is observed at D'~2.1 (normalized distance from the roadway by the width of the road). The indoor particle concentration is greater than that at the highway where D'building planning, the distance from the roadway and the ambient wind condition need to be considered at the early design stage whereas the size and location of the window openings, the interior layout, and the placement of fresh air intakes are important to the indoor air quality of existing buildings adjacent to roadways. Copyright © 2016 Elsevier Ltd. All rights reserved.

Experimental Analysis and Model Validation of an Opaque Ventilated Facade

DEFF Research Database (Denmark)

López, F. Peci; Jensen, Rasmus Lund; Heiselberg, Per

2012-01-01

Natural ventilation is a convenient way of reducing energy consumption in buildings. In this study an experimental module of an opaque ventilated façade (OVF) was built and tested for assessing its potential of supplying free ventilation and air preheating for the building. A numerical model was ...

Impact of Residential Mechanical Ventilation on Energy Cost and Humidity Control

Energy Technology Data Exchange (ETDEWEB)

Martin, Eric [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2014-01-01

The DOE Building America program has been conducting research leading to cost effective high performance homes since the early 1990's. Optimizing whole house mechanical ventilation as part of the program's systems engineered approach to constructing housing has been an important subject of the program's research. Ventilation in residential buildings is one component of an effective, comprehensive strategy for creation and maintenance of a comfortable and healthy indoor air environment. The study described in this white paper is based on building energy modeling with an important focus on the indoor humidity impacts of ventilation. The modeling tools used were EnergyPlus version 7.1 (E+) and EnergyGauge USA (EGUSA). Twelve U.S. cities and five climate zones were represented. A total of 864 simulations (2*2*3*3*12= 864) were run using two building archetypes, two building leakage rates, two building orientations, three ventilation systems, three ventilation rates, and twelve climates.

Design guidelines for natural ventilation systems in tertiary sector buildings

OpenAIRE

Van Moeseke, Geoffrey; Bruyère, Isabelle; De Herde, André; CISBAT 2005: Renewables in a changing climate

2005-01-01

Parameters determining efficiency of natural ventilation systems are numerous. The most important are architecture and system design. This article get onto both but focuses on system design. Through dynamic simulations it shows that natural ventilation management has a large impact on energy saving but most of all on thermal comfort. Natural ventilation techniques are also weighted against hybrid solutions and high efficiency mechanical cooling solutions. Natural ventilation techniques show t...

Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

Energy Technology Data Exchange (ETDEWEB)

Rudd, Armin [Building Science Corporation, Somerville, MA (United States); Bergey, Daniel [Building Science Corporation, Somerville, MA (United States)

2014-02-01

In this project, Building America research team Building Science Corporation tested the effectiveness of ventilation systems at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy. This was because the source of outside air was not direct from outside, the ventilation air was not distributed, and no provision existed for air filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four system factor categories: balance, distribution, outside air source, and recirculation filtration. Recommended system factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year.

Influence of radiation on predictive accuracy in numerical simulations of the thermal environment in industrial buildings with buoyancy-driven natural ventilation

International Nuclear Information System (INIS)

Meng, Xiaojing; Wang, Yi; Liu, Tiening; Xing, Xiao; Cao, Yingxue; Zhao, Jiangping

2016-01-01

Highlights: • The effects of radiation on predictive accuracy in numerical simulations were studied. • A scaled experimental model with a high-temperature heat source was set up. • Simulation results were discussed considering with and without radiation model. • The buoyancy force and the ventilation rate were investigated. - Abstract: This paper investigates the effects of radiation on predictive accuracy in the numerical simulations of industrial buildings. A scaled experimental model with a high-temperature heat source is set up and the buoyancy-driven natural ventilation performance is presented. Besides predicting ventilation performance in an industrial building, the scaled model in this paper is also used to generate data to validate the numerical simulations. The simulation results show good agreement with the experiment data. The effects of radiation on predictive accuracy in the numerical simulations are studied for both pure convection model and combined convection and radiation model. Detailed results are discussed regarding the temperature and velocity distribution, the buoyancy force and the ventilation rate. The temperature and velocity distributions through the middle plane are presented for the pure convection model and the combined convection and radiation model. It is observed that the overall temperature and velocity magnitude predicted by the simulations for pure convection were significantly greater than those for the combined convection and radiation model. In addition, the Grashof number and the ventilation rate are investigated. The results show that the Grashof number and the ventilation rate are greater for the pure convection model than for the combined convection and radiation model.

Why we ventilate our houses - An historical look

Energy Technology Data Exchange (ETDEWEB)

Matson, Nance E.; Sherman, Max H.

2004-05-14

The knowledge of how to ventilate buildings, and how much ventilation is necessary for human health and comfort, has evolved over centuries of trial and error. Humans and animals have developed successful solutions to the problems of regulating temperature and removing air pollutants through the use of ventilation. These solutions include ingenious construction methods, such as engineered passive ventilation (termite mounds and passive stacks), mechanical means (wing-powered, fans), and an evolving effort to identify problems and develop solutions. Ventilation can do more than help prevent building occupants from getting sick; it can provide an improved indoor environment. Codes and standards provide minimum legal requirements for ventilation, but the need for ventilation goes beyond code minima. In this paper we will look at indoor air pollutant sources over time, the evolution of ventilation strategies, current residential ventilation codes and standards (e.g., recently approved ASHRAE Standard 62.2), and briefly discuss ways in which we can go beyond the standards to optimize residential ventilation, reduce indoor air quality problems, and provide corresponding social and economic benefit.

Low home ventilation rate in combination with moldy odor from the building structure increase the risk for allergic symptoms in children

DEFF Research Database (Denmark)

Hägerhed-Engman, L.; Sigsgaard, T.; Samuelson, I.

2009-01-01

There are consistent findings on associations between asthma and allergy symptoms and residential mold and moisture. However, definitions of 'dampness' in studies are diverse because of differences in climate and building construction. Few studies have estimated mold problems inside the building...... ventilation rate in combination with moldy odor along the skirting board further increased the risk for three out of four studied outcomes, indicating that the ventilation rate is an effect modifier for indoor pollutants.This study showed that mold odor at the skirting board level is strongly associated...... with allergic symptoms among children. Such odor at that specific place can be seen as a proxy for some kind of hidden moisture or mold problem in the building structure, such as the foundation or wooden ground beam. In houses with odor along the skirting board, dismantling of the structure is required...

STTR Phase I: Low-Cost, High-Accuracy, Whole-Building Carbon Dioxide Monitoring for Demand Control Ventilation

Energy Technology Data Exchange (ETDEWEB)

Hallstrom, Jason; Ni, Zheng Richard

2018-05-15

This STTR Phase I project assessed the feasibility of a new CO2 sensing system optimized for low-cost, high-accuracy, whole-building monitoring for use in demand control ventilation. The focus was on the development of a wireless networking platform and associated firmware to provide signal conditioning and conversion, fault- and disruptiontolerant networking, and multi-hop routing at building scales to avoid wiring costs. Early exploration of a bridge (or “gateway”) to direct digital control services was also explored. Results of the project contributed to an improved understanding of a new electrochemical sensor for monitoring indoor CO2 concentrations, as well as the electronics and networking infrastructure required to deploy those sensors at building scales. New knowledge was acquired concerning the sensor’s accuracy, environmental response, and failure modes, and the acquisition electronics required to achieve accuracy over a wide range of CO2 concentrations. The project demonstrated that the new sensor offers repeatable correspondence with commercial optical sensors, with supporting electronics that offer gain accuracy within 0.5%, and acquisition accuracy within 1.5% across three orders of magnitude variation in generated current. Considering production, installation, and maintenance costs, the technology presents a foundation for achieving whole-building CO2 sensing at a price point below $0.066 / sq-ft – meeting economic feasibility criteria established by the Department of Energy. The technology developed under this award addresses obstacles on the critical path to enabling whole-building CO2 sensing and demand control ventilation in commercial retrofits, small commercial buildings, residential complexes, and other highpotential structures that have been slow to adopt these technologies. It presents an opportunity to significantly reduce energy use throughout the United States a

Humidification policies for mechanically ventilated intensive care patients and prevention of ventilator-associated pneumonia: a systematic review of randomized controlled trials.

Science.gov (United States)

Niël-Weise, B S; Wille, J C; van den Broek, P J

2007-04-01

The Dutch Working Party on Infection Prevention (WIP) aimed to determine whether certain humidification policies are better than others in terms of prevention of ventilator-associated pneumonia (VAP) in mechanically ventilated intensive care unit (ICU) patients. Publications were retrieved by a systematic search of Medline and the Cochrane Library up to February 2006. All (quasi-) randomized trials and systematic reviews/meta-analyses comparing humidification methods in ventilated ICU patients were selected. Two reviewers independently assessed trial quality and extracted data. If the data was incomplete, clarification was sought from original authors and used to calculate the relative risk of VAP. Data for VAP were combined in the analysis, where appropriate, using a random-effects model. Ten trials were included in the review. In general, the quality of the trials and the way they were reported were unsatisfactory. The results did not show any benefit from specific humidification techniques in terms of reducing VAP. WIP do not recommend either passive or active humidifiers to prevent VAP, nor the type of passive humidifiers to be used. Regarding active humidification, WIP recommends using heated wire circuits. This is due to the theoretical consideration that less condensate reduces colonization and subsequent risk of spread throughout an ICU when condensate is removed.

Measure Guideline: Ventilation Guidance for Residential High-Performance New Construction - Multifamily

Energy Technology Data Exchange (ETDEWEB)

Lstiburek, Joseph [Building Science Corporation, Westford, MA (United States)

2017-01-01

The measure guideline provides ventilation guidance for residential high performance multifamily construction that incorporates the requirements of the ASHRAE 62.2 ventilation and indoor air quality standard. The measure guideline focus is on the decision criteria for weighing cost and performance of various ventilation systems. The measure guideline is intended for contractors, builders, developers, designers and building code officials. The guide may also be helpful to building owners wishing to learn more about ventilation strategies available for their buildings. The measure guideline includes specific design and installation instructions for the most cost effective and performance effective solutions for ventilation in multifamily units that satisfies the requirements of ASHRAE 62.2-2016.

Implementing nationally determined contributions: building energy policies in India’s mitigation strategy

Science.gov (United States)

Yu, Sha; Evans, Meredydd; Kyle, Page; Vu, Linh; Tan, Qing; Gupta, Ashu; Patel, Pralit

2018-03-01

The Nationally Determined Contributions are allowing countries to examine options for reducing emissions through a range of domestic policies. India, like many developing countries, has committed to reducing emissions through specific policies, including building energy codes. Here we assess the potential of these sectoral policies to help in achieving mitigation targets. Collectively, it is critically important to see the potential impact of such policies across developing countries in meeting national and global emission goals. Buildings accounted for around one third of global final energy use in 2010, and building energy consumption is expected to increase as income grows in developing countries. Using the Global Change Assessment Model, this study finds that implementing a range of energy efficiency policies robustly can reduce total Indian building energy use by 22% and lower total Indian carbon dioxide emissions by 9% in 2050 compared to the business-as-usual scenario. Among various policies, energy codes for new buildings can result in the most significant savings. For all building energy policies, well-coordinated, consistent implementation is critical, which requires coordination across different departments and agencies, improving capacity of stakeholders, and developing appropriate institutions to facilitate policy implementation.

Ventilation rates and health

DEFF Research Database (Denmark)

Sundell, Jan; Levin, H; Nazaroff, W W

2011-01-01

and health effects to inform the relationship. Consistency was found across multiple investigations and different epidemiologic designs for different populations. Multiple health endpoints show similar relationships with ventilation rate. There is biological plausibility for an association of health outcomes...... studies of the relationship between ventilation rates and health, especially in diverse climates, in locations with polluted outdoor air and in buildings other than offices. PRACTICAL IMPLICATIONS: Ventilation with outdoor air plays an important role influencing human exposures to indoor pollutants...

Low resource ventilation unit; Ressourcebesparende ventilationsenhed

Energy Technology Data Exchange (ETDEWEB)

Drivsholm, C.

2012-03-15

In the project a resource-saving ventilation device was developed which is based on the use of a regenerator and a reversible air flow. The regenerator is placed in the building envelope, and the concept works in the way that the heat in the air during ventilation is stored in the regenerator and brought back into the building by a reversible air change. The heated air is blown from inside the building out through the regenerator. In this way the regenerator accumulates the heat in the air. Over a period of 30-120 seconds, the regenerator capacity is utilized. When the regenerator cannot be further heated, the air flow is reversed and there is now blown cold air through the regenerator. Thereby the heat from the regenerator is released to the cold fresh air. Thus, the fresh air brings heat back into the building, whereby the air is replaced with a limited heat loss. Ventilation with a regenerator is described as micro-ventilation. The developed micro-ventilation unit was tested by the Danish Technological Institute. The test results shows that the unit performs according to expectations: 1) The heat recovery is 85%; 2) The flow through the unit is 80m3 per hour in a 5 section unit; 3) The noise level is 30 db(A) in a representative room; 4) The energy consumption is <300 J/m3. The unit is introduced into the market, and the first plants have been sold. (LN)

CFD and Ventilation Research

DEFF Research Database (Denmark)

Li, Y.; Nielsen, Peter V.

2011-01-01

There has been a rapid growth of scientific literature on the application of computational fluid dynamics (CFD) in the research of ventilation and indoor air science. With a 1000–10,000 times increase in computer hardware capability in the past 20 years, CFD has become an integral part...... of scientific research and engineering development of complex air distribution and ventilation systems in buildings. This review discusses the major and specific challenges of CFD in terms of turbulence modelling, numerical approximation, and boundary conditions relevant to building ventilation. We emphasize...... the growing need for CFD verification and validation, suggest on-going needs for analytical and experimental methods to support the numerical solutions, and discuss the growing capacity of CFD in opening up new research areas. We suggest that CFD has not become a replacement for experiment and theoretical...

Feedback effect of human physical and psychological adaption on time period of thermal adaption in naturally ventilated building

DEFF Research Database (Denmark)

liu, weiwei; Huangfu, Hao; Xiong, Jing

2014-01-01

This study proposed a method to determine time period of thermal adaption for occupants in naturally ventilated building, and analyzed the synergistic and separate feedback effect of the physical and psychological adaption modes on the time period of thermal adaption. Using the method, the values...... of the time period of thermal adaption were obtained on the basis of the data from a long-term field survey conducted in two typical naturally ventilated offices located in Changsha, China. The results showed that the occupants need to take 4.25 days to fully adapt to a step-change in outdoor air temperature...

Effect of ventilation type on radon concentration at places of work

International Nuclear Information System (INIS)

Oksanen, E.

1994-01-01

Indoor radon ( 222 Rn) concentrations were measured at 76 child care facilities and 36 schools in southern Finland. The buildings had three different types of ventilation systems: mechanical air supply and exhaust, mechanical exhaust, and natural ventilation, the first being most common. The effect of the ventilation type on the long-term radon concentration was studied in child care facilities. The radon concentrations were highest in the naturally ventilated buildings. The mechanical air supply and exhaust system maintained the lowest values in cold wintertime. In school buildings both the long-term radon concentration and short-term radon and daughter concentrations were measured. The correlation of the ventilation type and the radon concentration was not obvious in this group of measurements, but the radon concentrations and the equilibrium factors were highest in buildings with natural ventilation. Radon concentrations were generally lower during the working hours than during the one-month period, as expected. (author)

Design Principles for Natural and Hybrid Ventilation

DEFF Research Database (Denmark)

Heiselberg, Per

For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system- Hybrid Ventilation. ....... The hybrid ventilation concepts, design challenges and principles are discussed and illustrated by four building examples.......For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system- Hybrid Ventilation...

To Investigate the Influence of Building Envelope and Natural Ventilation on Thermal Heat Balance in Office Buildings in Warm and Humid Climate

Science.gov (United States)

Kini, Pradeep G.; Garg, Naresh Kumar; Kamath, Kiran

2017-07-01

India’s commercial building sector is witnessing robust growth. India continues to be a key growth market among global corporates and this is reflective in the steady growth in demand for prime office space. A recent trend that has been noted is the increase in demand for office spaces not just in major cities but also in smaller tier II and Tier III cities. Growth in the commercial building sector projects a rising trend of energy intensive mechanical systems in office buildings in India. The air conditioning market in India is growing at 25% annually. This is due to the ever increasing demand to maintain thermal comfort in tropical regions. Air conditioning is one of the most energy intensive technologies which are used in buildings. As a result India is witnessing significant spike in energy demand and further widening the demand supply gap. Challenge in India is to identify passive measures in building envelope design in office buildings to reduce the cooling loads and conserve energy. This paper investigates the overall heat gain through building envelope components and natural ventilation in warm and humid climate region through experimental and simulation methods towards improved thermal environmental performance.

Assessment of the seismic resistance of a ventilation stack on a reactor building

International Nuclear Information System (INIS)

Makovicka, Daniel; Makovicka, Daniel

2005-01-01

The paper analyzes the seismic resistance of a ventilation stack on a reactor building, including the possible reserves of increasing the resistance. Structures of this type are highly sensitive to seismic loads, as the tuning of the stack (the spectrum of its lowest natural frequencies) corresponds with the frequency spectrum of excitation due to seismic effects. The purpose of the paper is to present an example of an actual structure to show the character of the response of the structure, and the participation of the individual frequency components of the response in the overall stress and strain state of a structure of this type. The methodology for a numerical analysis of the structure is also given. The load of the stack proper is modified by the transfer characteristics of the building. In engineering practice, the system is usually divided into two subsystems: the building with the sub-base, and the stack proper. The level of justification for the application of this simplification depends on the distance of the natural frequencies of the stack from the natural frequencies of the building. Finally, the paper deals with possible errors in determining the actual seismic resistance of the stack structure

Effect of a ventilator-focused intervention on the rate of Acinetobacter baumannii infection among ventilated patients.

Science.gov (United States)

Cohen, Regev; Shimoni, Zvi; Ghara, Riad; Ram, Ron; Ben-Ami, Ronen

2014-09-01

Acinetobacter baumannii is a leading cause of ventilator-associated pneumonia, often as a result of ventilator equipment contamination. Evidence-based guidance on optimal care of ventilator equipment to prevent infection is lacking. Here, we report on a significant and persistent reduction in A baumannii infection rates achieved by introducing a strict policy on ventilator care. We implemented an institution-wide ventilator care policy that included routine exchange of breathing circuits and external bacterial filters (every 7-14 days) and replacement followed by routine sterilization of internal bacterial filters (every 4-8 weeks). We analyzed sputum cultures and patient outcomes among ventilated patients before and after the intervention. Between January 2012 and March 2013, 321 patients ventilated for more than 3 days comprised the study cohort. Health care-associated A baumannii acquisition was significantly reduced during the postintervention period (33% vs 16%; odds ratio, 0.39; 95% confidence interval, 0.23-0.67; P = .0008). Additionally, the median time to A baumannii acquisition was significantly longer postintervention (59 vs 21 days; P < .0001). A baumannii ventilator-associated pneumonia risk was also reduced postintervention (odds ratio, 0.39; P = .005). Implementing a stricter standard of ventilator care than that currently defined in published guidelines can significantly decrease health care-associated A baumannii acquisition and related adverse outcomes among ventilated patients. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

International Ventilation Cooling Application Database

DEFF Research Database (Denmark)

Holzer, Peter; Psomas, Theofanis Ch.; OSullivan, Paul

2016-01-01

The currently running International Energy Agency, Energy and Conservation in Buildings, Annex 62 Ventilative Cooling (VC) project, is coordinating research towards extended use of VC. Within this Annex 62 the joint research activity of International VC Application Database has been carried out...... and locations, using VC as a mean of indoor comfort improvement. The building-spreadsheet highlights distributions of technologies and strategies, such as the following. (Numbers in % refer to the sample of the database’s 91 buildings.) It may be concluded that Ventilative Cooling is applied in temporary......, systematically investigating the distribution of technologies and strategies within VC. The database is structured as both a ticking-list-like building-spreadsheet and a collection of building-datasheets. The content of both closely follows Annex 62 State-Of-The- Art-Report. The database has been filled, based...

Apartment building built to passive-house standard with solar balanced ventilation system; Mehrfamilien-Passivhaus mit solarem Luftsystem. Lueftung/Luftheizung/WRG/Solarfassade an der Rychenbergstrasse, Winterthur - Schlussbericht

Energy Technology Data Exchange (ETDEWEB)

Guetermann, A.

2002-04-15

This final report for the Swiss Federal Office of Energy (SFOE) deals with an apartment building in Winterthur, Switzerland, built to passive-house standards and equipped with a solar balanced ventilation system. The building and its convective solar facade are described, as are the fan-assisted, balanced ventilation systems used. The operation of the systems in winter, during transitional periods and in summer is discussed. Domestic hot water preparation is looked at. The energy balance of the building is examined, as is the economic viability of the energy systems. The building, its energy installations and the measurement concept used are considered in detail. Finally, the findings of the study are summarised and commented on.

Modelling inspection policies for building maintenance.

Science.gov (United States)

Christer, A H

1982-08-01

A method of assessing the potential of an inspection maintenance policy as opposed to an existing breakdown maintenance policy for a building complex is developed. The method is based upon information likely to be available and specific subjective assessments which could be made available. Estimates of the expected number of defects identified at an inspection and the consequential cost saving are presented as functions of the inspection frequency.

Building Energy Codes: Policy Overview and Good Practices

Energy Technology Data Exchange (ETDEWEB)

Cox, Sadie [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-02-19

Globally, 32% of total final energy consumption is attributed to the building sector. To reduce energy consumption, energy codes set minimum energy efficiency standards for the building sector. With effective implementation, building energy codes can support energy cost savings and complementary benefits associated with electricity reliability, air quality improvement, greenhouse gas emission reduction, increased comfort, and economic and social development. This policy brief seeks to support building code policymakers and implementers in designing effective building code programs.

Ventilating Air-Conditioner

Science.gov (United States)

Dinh, Khanh

1994-01-01

Air-conditioner provides ventilation designed to be used alone or incorporated into cooling or heating system operates efficiently only by recirculating stale air within building. Energy needed to operate overall ventilating cooling or heating system slightly greater than operating nonventilating cooling or heating system. Helps to preserve energy efficiency while satisfying need for increased forced ventilation to prevent accumulation of undesired gases like radon and formaldehyde. Provides fresh treated air to variety of confined spaces: hospital surgeries, laboratories, clean rooms, and printing shops and other places where solvents used. In mobile homes and portable classrooms, eliminates irritant chemicals exuded by carpets, panels, and other materials, ensuring healthy indoor environment for occupants.

Analysis of intelligent green building policy and developing status in Taiwan

International Nuclear Information System (INIS)

Kuo, Chung-Feng Jeffrey; Lin, Chieh-Hung; Hsu, Ming-Wen

2016-01-01

In 2010, Taiwan launched a program dubbed “four emerging intellectual industries” that lists intelligent green buildings. The aim of promoting of intelligent green building is to stimulate the architecture technology industry. This has been combined with Information and Communication Technology (ICT) and the concept of green building to provide a safe and healthy living environment. While doing this it will also aim to reduce carbon emissions and save energy. This study investigates intelligent green building policies and the promotion of progress in Taiwan. It probes into cases from 1988 to 2014. Key success factors are derived from analyzing and summarizing intelligent green building experiences in Taiwan. This is done through Secondary Data Analyses by: 1. Establishing clear norms and standards for intelligent green building design and improvement; 2. First carrying out policies in public sector, in order to provide field trial and safeguarded market opportunities for industries; 3. Implementing rating-based assessments, in order to raise the quality of design; 4. Mandatory or incentive policies are introduced, depending on local specialties and conditions; 5. Respectively planning incentives for relevant interested parties in industrial chain; 6. Strengthening marketing efforts and proactively promoting policies. - Highlights: •Aggregate and analyze the results of Intelligent Green Building policy in Taiwan. •Chi-square Test of Independence is used for inspecting successful factors. •Organize experiences and propose recommended feasible scheme for future.

Ventilation and air-conditioning system for PWR nuclear power plant

International Nuclear Information System (INIS)

Ohmoto, Kenji

1987-01-01

This report outlines the ventilation and air conditioning facilities for PWR nuclear power plant as well as design re-evaluation and optimization of ventilation and air-conditioning. The primary PWR installations are generally housed in the nuclear reactor building, auxiliary buildings and control building, which are equipped with their own ventilation and air-conditioning systems to serve for their specific purposes. A ventilation/air-conditioning system should be able to work effectively not only for maintaining the ordinary reactor operation but also for controlling the environmental temperature in the event of an accident. Designing of a ventilation/air-conditioning system relied on empirical data in the past, but currently it is performed based on information obtained from various analyses to optimize the system configuration and ventilation capacity. Design re-evaluation of ventilation/air-conditioning systems are conducted widely in various areas, aiming at the integration of safety systems, optimum combination of air-cooling and water-cooling systems, and optimization of the ventilation rate for controlling the concentrations of radioactive substances in the atmosphere in the facilities. It is pointed out that performance evaluation of ventilation/air-conditioning systems, which has been conducted rather macroscopically, should be carried out more in detal in the future to determine optimum air streams and temperature distribution. (Nogami, K.)

Natural Ventilation Driven by Wind and Temperature Difference

DEFF Research Database (Denmark)

Larsen, Tine Steen

Natural ventilation is a commonly used principle when buildings are being ventilated. It can be controlled by openings in the building envelope, which open or close depending on the need of air inside the building. It can also be the simple action of just opening a door or a window to let the fresh...... driving forces are still wind pressure and temperature differences as with cross-ventilation, but here the turbulence in the wind and the pulsating flow near the opening also affect the flow through the opening. From earlier work, some design expressions already exist, but none of these include...... the incidence angle of the wind, which is an important parameter in this type of ventilation. Several wind tunnel experiments are made and from the results of these, a new design expression is made which includes the wind pressure, temperature difference, incidence angle of the wind and the fluctuations...

Passive ventilation systems with heat recovery and night cooling

DEFF Research Database (Denmark)

Hviid, Christian Anker; Svendsen, Svend

2008-01-01

with little energy consumption and with satisfying indoor climate. The concept is based on using passive measures like stack and wind driven ventilation, effective night cooling and low pressure loss heat recovery using two fluid coupled water-to-air heat exchangers developed at the Technical University......In building design the requirements for energy consumption for ventilation, heating and cooling and the requirements for increasingly better indoor climate are two opposing factors. This paper presents the schematic layout and simulation results of an innovative multifunc-tional ventilation concept...... of Denmark. Through building integration in high performance offices the system is optimized to incorporate multiple functions like heating, cooling and ventilation, thus saving the expenses of separate cooling and heating systems. The simulation results are derived using the state-of-the-art building...

Air Distribution and Ventilation Effectiveness in a room with Floor/Ceiling Heating and Mixing/Displacement Ventilation

DEFF Research Database (Denmark)

Wu, Xiaozhou; Fang, Lei; Olesen, Bjarne W.

2014-01-01

vertical air temperature differences and air velocities for different hybrid systems are less than 3 C and 0.2 m/s when supply air temperature is 19 C, air change rate is 4.2 h-1, and heated surface temperature of floor/ceiling heating system is 25 C. Ventilation effectiveness of mixing ventilation system...... combined with floor/ceiling heating systems is approximately equal to 1.0, and ventilation effectiveness of displacement ventilation system combined with floor/ceiling heating systems ranges from 1.0 to 1.2. The floor/ceiling heating systems combined with mixing ventilation system have more uniform indoor...... air distribution but smaller ventilation effectiveness compared with the floor/ceiling heating systems combined with displacement ventilation system. With regard to the building heat loss increased by non-uniform indoor air distribution and small ventilation effectiveness, there should be an optimal...

Outcome-based ventilation: A framework for assessing performance, health, and energy impacts to inform office building ventilation decisions.

Science.gov (United States)

Rackes, A; Ben-David, T; Waring, M S

2018-04-23

This article presents an outcome-based ventilation (OBV) framework, which combines competing ventilation impacts into a monetized loss function ($/occ/h) used to inform ventilation rate decisions. The OBV framework, developed for U.S. offices, considers six outcomes of increasing ventilation: profitable outcomes realized from improvements in occupant work performance and sick leave absenteeism; health outcomes from occupant exposure to outdoor fine particles and ozone; and energy outcomes from electricity and natural gas usage. We used the literature to set low, medium, and high reference values for OBV loss function parameters, and evaluated the framework and outcome-based ventilation rates using a simulated U.S. office stock dataset and a case study in New York City. With parameters for all outcomes set at medium values derived from literature-based central estimates, higher ventilation rates' profitable benefits dominated negative health and energy impacts, and the OBV framework suggested ventilation should be ≥45 L/s/occ, much higher than the baseline ~8.5 L/s/occ rate prescribed by ASHRAE 62.1. Only when combining very low parameter estimates for profitable impacts with very high ones for health and energy impacts were all outcomes on the same order. Even then, however, outcome-based ventilation rates were often twice the baseline rate or more. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Measure Guideline: Selecting Ventilation Systems for Existing Homes

Energy Technology Data Exchange (ETDEWEB)

Aldrich, R. [Consortium for Advanced Residential Buildings (CARB), Norwalk, CT (United States)

2014-02-01

This report, developed by Building America research team CARB, addresses adding or improving mechanical ventilation systems to existing homes. The goal of this report is to assist decision makers and contractors in making informed decisions when selecting ventilation systems for homes. With more air-sealed envelopes, a mechanical means of removing contaminants is critical for indoor environmental quality and building durability. The purpose of ventilation is to remove contaminants from homes, and this report discusses where, when, and how much ventilation is appropriate in a home, including examination of relevant codes and standards. Choosing the "best" system is not always straightforward; selecting a system involves balancing performance, efficiency, cost, required maintenance, and several other factors.

Thermoregulation and ventilation of termite mounds

Science.gov (United States)

Korb, Judith

2003-05-01

Some of the most sophisticated of all animal-built structures are the mounds of African termites of the subfamily Macrotermitinae, the fungus-growing termites. They have long been studied as fascinating textbook examples of thermoregulation or ventilation of animal buildings. However, little research has been designed to provide critical tests of these paradigms, derived from a very small number of original papers. Here I review results from recent studies on Macrotermes bellicosus that considered the interdependence of ambient temperature, thermoregulation, ventilation and mound architecture, and that question some of the fundamental paradigms of termite mounds. M. bellicosus achieves thermal homeostasis within the mound, but ambient temperature has an influence too. In colonies in comparably cool habitats, mound architecture is adapted to reduce the loss of metabolically produced heat to the environment. While this has no negative consequences in small colonies, it produces a trade-off with gas exchange in large colonies, resulting in suboptimally low nest temperatures and increased CO2 concentrations. Along with the alteration in mound architecture, the gas exchange/ventilation mechanism also changes. While mounds in the thermally appropriate savannah have a very efficient circular ventilation during the day, the ventilation in the cooler forest is a less efficient upward movement of air, with gas exchange restricted by reduced surface exchange area. These results, together with other recent findings, question entrenched ideas such as the thermosiphon-ventilation mechanism or the assumption that mounds function to dissipate internally produced heat. Models trying to explain the proximate mechanisms of mound building, or building elements, are discussed.

Hybrid ventilation in residential buildings – the proposal of research for the Polish climatic conditions

Directory of Open Access Journals (Sweden)

Kostka Maria

2017-01-01

Full Text Available Due to the geographic location and the influence of the polar maritime and polar continental air masses we observe a large variety and variability of external air parameters in Poland. Both during the whole year and also in shorter, even several-day periods. The parameters of outside air indicate that combination of mechanical and natural ventilation in detached buildings can be cost-effective and allows keeping the thermal comfort and good indoor air quality.

Modeling and Control of Livestock Ventilation Systems and Indoor Environments

DEFF Research Database (Denmark)

Wu, Zhuang; Heiselberg, Per; Stoustrup, Jakob

2005-01-01

The hybrid ventilation systems have been widely used for livestock barns to provide optimum indoor climate by controlling the ventilation rate and air flow distribution within the ventilated building structure. The purpose of this paper is to develop models for livestock ventilation systems and i...

Energy Savings Potential and Research, Development, & Demonstration Opportunities for Residential Building Heating, Ventilation, and Air Conditioning Systems

Energy Technology Data Exchange (ETDEWEB)

Goetzler, William [Navigant Consulting, Inc., Burlington, MA (United States); Zogg, Robert [Navigant Consulting, Inc., Burlington, MA (United States); Young, Jim [Navigant Consulting, Inc., Burlington, MA (United States); Schmidt, Justin [Navigant Consulting, Inc., Burlington, MA (United States)

2012-10-01

This report is an assessment of 135 different heating, ventilation, and air-conditioning (HVAC) technologies for U.S. residential buildings to identify and provide analysis on 19 priority technology options in various stages of development. The analyses include an estimation of technical energy-savings potential, descriptions of technical maturity, descriptions of non-energy benefits, descriptions of current barriers for market adoption, and descriptions of the technology's applicability to different building or HVAC equipment types. From these technology descriptions, are suggestions for potential research, development and demonstration (RD&D) initiatives that would support further development of the priority technology options.

Energy Savings Potential and Research, Development, & Demonstration Opportunities for Commercial Building Heating, Ventilation, and Air Conditioning Systems

Energy Technology Data Exchange (ETDEWEB)

none,

2011-09-01

This report covers an assessment of 182 different heating, ventilation, and air-conditioning (HVAC) technologies for U.S. commercial buildings to identify and provide analysis on 17 priority technology options in various stages of development. The analyses include an estimation of technical energy-savings potential, description of technical maturity, description of non-energy benefits, description of current barriers for market adoption, and description of the technology’s applicability to different building or HVAC equipment types. From these technology descriptions, are suggestions for potential research, development and demonstration (RD&D) initiatives that would support further development of the priority technology options.

Costs and Benefits of Implementing Green Building Policy

NARCIS (Netherlands)

Fan, Ke; Wei, G; Qian, K.; Chan, E

2017-01-01

Green building (GB) policies have been implemented to promote GB and address climate change. Most of the existing literatures have studied the costs and benefits of developing GB, without considerations of GB policies’ impacts. This paper aims to study costs and benefits of implementing GB policy

Developing evidence-based prescriptive ventilation rate standards for commercial buildings in California: a proposed framework

Energy Technology Data Exchange (ETDEWEB)

Mendell, Mark J.; Fisk, William J.

2014-02-01

Background - The goal of this project, with a focus on commercial buildings in California, was to develop a new framework for evidence-based minimum ventilation rate (MVR) standards that protect occupants in buildings while also considering energy use and cost. This was motivated by research findings suggesting that current prescriptive MVRs in commercial buildings do not provide occupants with fully safe and satisfactory indoor environments. Methods - The project began with a broad review in several areas ? the diverse strategies now used for standards or guidelines for MVRs or for environmental contaminant exposures, current knowledge about adverse human effects associated with VRs, and current knowledge about contaminants in commercial buildings, including their their presence, their adverse human effects, and their relationships with VRs. Based on a synthesis of the reviewed information, new principles and approaches are proposed for setting evidence-based VRs standards for commercial buildings, considering a range of human effects including health, performance, and acceptability of air. Results ? A review and evaluation is first presented of current approaches to setting prescriptive building ventilation standards and setting acceptable limits for human contaminant exposures in outdoor air and occupational settings. Recent research on approaches to setting acceptable levels of environmental exposures in evidence-based MVR standards is also described. From a synthesis and critique of these materials, a set of principles for setting MVRs is presented, along with an example approach based on these principles. The approach combines two sequential strategies. In a first step, an acceptable threshold is set for each adverse outcome that has a demonstrated relationship to VRs, as an increase from a (low) outcome level at a high reference ventilation rate (RVR, the VR needed to attain the best achievable levels of the adverse outcome); MVRs required to meet each

Methods for measuring gas emissions from naturally ventilated livestock buildings: Developments over the last decade and perspectives for improvement

NARCIS (Netherlands)

Ogink, N.W.M.; Mosquera Losada, J.; Calvet, S.; Zhang, G.

2013-01-01

The objectives of this paper are: 1) to give an overview of the development of methods for measuring emission rates from naturally ventilated livestock buildings over the last decade, 2) to identify and evaluate strengths and weaknesses, 3) to summarise and conclude the current state-of-art of

Healthy Zero Energy Buildings (HZEB) Program - Cross-Sectional Study of Contaminant Levels, Source, Strengths, and Ventilation Rates in Retail Stores

Energy Technology Data Exchange (ETDEWEB)

Chan, Wanyu R.; Sidheswaran, Meera; Cohn, Sebastian; Sullivan, Douglas P.; Fisk, William

2014-02-01

This field study measured ventilation rates and indoor air quality parameters in 21 visits to retail stores in California. The data was collected to guide the development of new, science-based commercial building ventilation rate standards that balance the dual objectives of increasing energy efficiency and maintaining acceptable indoor air quality. Data collection occurred between September 2011 and March 2013. Three types of stores participated in this study: grocery stores, furniture/hardware stores, and apparel stores. Ventilation rates and indoor air contaminant concentrations were measured on a weekday, typically between 9 am and 6 pm. Ventilation rates measured using a tracer gas decay method exceeded the minimum requirement of California’s Title 24 Standard in all but one store. Even though there was adequate ventilation according to Title 24, concentrations of formaldehyde, acetaldehyde, and acrolein exceeded the most stringent chronic health guidelines. Other indoor air contaminants measured included carbon dioxide (CO{sub 2}), carbon monoxide (CO), ozone (O{sub 3}), and particulate matter (PM). Concentrations of CO{sub 2} were kept low by adequate ventilation, and were assumed low also because the sampling occurred on a weekday when retail stores were less busy. CO concentrations were also low. The indoor-outdoor ratios of O{sub 3} showed that the first-order loss rate may vary by store trade types and also by ventilation mode (mechanical versus natural). Analysis of fine and ultrafine PM measurements showed that a substantial portion of the particle mass in grocery stores with cooking-related emissions was in particles less than 0.3 μm. Stores without cooking as an indoor source had PM size distributions that were more similar indoors and outdoors. The whole-building emission rates of volatile organic compounds (VOCs) and PM were estimated from the measured ventilation rates and indoor and outdoor contaminant concentrations. Mass balance models were

Indoor-outdoor concentrations of RSPM in classroom of a naturally ventilated school building near an urban traffic roadway

Science.gov (United States)

Goyal, Radha; Khare, Mukesh

2009-12-01

A study on indoor-outdoor RSPM (PM 10, PM 2.5 and PM 1.0) mass concentration monitoring has been carried out at a classroom of a naturally ventilated school building located near an urban roadway in Delhi City. The monitoring has been planned for a year starting from August 2006 till August 2007, including weekdays (Monday, Wednesday and Friday) and weekends (Saturday and Sunday) from 8:0 a.m. to 2:0 p.m., in order to take into account hourly, daily, weekly, monthly and seasonal variations in pollutant concentrations. Meteorological parameters, including temperature, rH, pressure, wind speed and direction, and traffic parameters, including its type and volume has been monitored simultaneously to relate the concentrations of indoor-outdoor RSPM with them. Ventilation rate has also been estimated to find out its relation with indoor particulate concentrations. The results of the study indicates that RSPM concentrations in classroom exceeds the permissible limits during all monitoring hours of weekdays and weekends in all seasons that may cause potential health hazards to occupants, when exposed. I/O for all sizes of particulates are greater than 1, which implies that building envelop does not provide protection from outdoor pollutants. Further, a significant influence of meteorological parameters, ventilation rate and of traffic has been observed on I/O. Higher I/O for PM 10 is indicating the presence of its indoor sources in classroom and their indoor concentrations are strongly influenced by activities of occupants during weekdays.

The State-of-the-Art for Ventilative Cooling

DEFF Research Database (Denmark)

Heiselberg, Per Kvols

2016-01-01

Ventilative cooling for buildings may lead to cooling energy savings and improvements in thermal comfort, especially in seasonally temperate and warm climates. But, codes and regulations need to better quantify its benefits.......Ventilative cooling for buildings may lead to cooling energy savings and improvements in thermal comfort, especially in seasonally temperate and warm climates. But, codes and regulations need to better quantify its benefits....

Potential of Ventilation Radiators: Performance evaluation by numerical, analytical and experimental means

Energy Technology Data Exchange (ETDEWEB)

Myhren, Jonn Are

2011-07-01

Energy consumption for heating and ventilation of buildings is still in 2011 considered far too high, but there are many ways to save energy and construct low energy buildings that have not been fully utilised. This doctoral thesis has focused on one of these - low temperature heating systems. Particular attention has been given to the ventilation radiator adapted for exhaust-ventilated buildings because of its potential as a low energy consuming, easily-operated, environmentally-friendly system that might also ensure occupant health and well-being. Investigations were based on Computational Fluid Dynamics (CFD) simulations and analytical calculations, with laboratory experiments used for validation. Main conclusions: - Low and very low temperature heating systems, such as floor heating, in general create an indoor climate with low air speeds and low temperature differences in the room, which is beneficial for thermal comfort. A typical disadvantage, however, was found to be weakness in counteracting cold down-flow from ventilation air supply units in exhaust ventilated buildings. - with ventilation radiators, unlike most other low temperature systems, it was found that the risk of cold draught could be reduced while still maintaining a high ventilation rate even in cold northern European winters. - ventilation radiators were found to be more thermally efficient than traditional radiators. - design of ventilation radiators could be further modified for improved thermal efficiency. - at an outdoor temperature of -15 deg. C the most efficient models were able to give double the heat output of traditional radiators. Also, by substituting the most efficient ventilation radiators for traditional radiators operating at 55 deg. C supply water temperature, it was found that supply water temperature could be reduced to 35 deg. C while heat output remained the same and comfort criteria were met. - lowering the supply water temperature by 20 deg. C (as described above) could

Environmental performance of a naturally ventilated city centre library

Energy Technology Data Exchange (ETDEWEB)

Krausse, Birgit; Cook, Malcolm; Lomas, Kevin [Institute of Energy and Sustainable Development, De Montfort University, Queens Building, The Gateway, Leicester LE1 9BH, (United Kingdom)

2007-07-15

To tackle climate change it is essential to reduce carbon dioxide emissions. To this end, it is important to reduce the energy demands of non-domestic buildings. Naturally ventilated buildings can have low energy demands but the strategy is difficult to implement in deep plan, urban locations. The Frederick Lanchester Library at Coventry University, UK, incorporates natural ventilation, daylighting and passive cooling strategies. By using lightwells and perimeter stacks to supply and exhaust air, it can be ventilated by natural means despite its deep plan form and sealed facade. This paper describes the building and presents the energy consumption and the internal temperatures and CO{sub 2} levels recorded in 2004/2005. The building's performance is compared to the original design criteria and good practice guidelines. Recommendations for the design of such buildings are made and the likely performance in other UK cities is assessed. It is concluded that the building uses under half the energy of a standard air-conditioned building and yet, in summer, can keep the interior comfortable and up to 5 deg C below ambient. The design would perform equally well in the typical weather conditions experienced at 13 other UK cities, but not in London. It is concluded that deep-plan, naturally ventilated buildings with sealed facades, if well designed, could maintain thermal comfort in all but a very few UK locations, whilst consuming much less energy than even good practice standards. (Author)

Building-integrated renewable energy policy analysis in China

Institute of Scientific and Technical Information of China (English)

姚春妮; 郝斌

2009-01-01

With the dramatic development of renewable energy all over the world,and for purpose of adjusting energy structure,the Ministry of Construction of China plans to promote the large scale application of renewable energy in buildings. In order to ensure the validity of policy-making,this work firstly exerts a method to do cost-benefit analysis for three kinds of technologies such as building-integrated solar hot water (BISHW) system,building-integrated photovoltaic (BIPV) technology and ground water heat pump (GWHP). Through selecting a representative city of every climate region,the analysis comes into different results for different climate regions in China and respectively different suggestion for policy-making. On the analysis basis,the Ministry of Construction (MOC) and the Ministry of Finance of China (MOF) united to start-up Building-integrated Renewable Energy Demonstration Projects (BIREDP) in 2006. In the demonstration projects,renewable energy takes place of traditional energy to supply the domestic hot water,electricity,air-conditioning and heating. Through carrying out the demonstration projects,renewable energy related market has been expanded. More and more relative companies and local governments take the opportunity to promote the large scale application of renewable energy in buildings.

Radon mitigation in schools utilising heating, ventilating and air conditioning systems

International Nuclear Information System (INIS)

Fisher, G.; Ligman, B.; Brennan, T.; Shaughnessy, R.; Turk, B.H.; Snead, B.

1994-01-01

As part of a continuing radon in schools technology development effort, EPA's School Evaluation Team has performed radon mitigation in schools by the method of ventilation/pressurisation control technology. Ventilation rates were increased, at a minimum, to meet the American Society of Heating, Refrigeration and Air Conditioning Engineers (ASHRAE) standard, Ventilation for Acceptable Indoor Air Quality (ASHRAE 62-1989). This paper presents the results and the preliminary evaluations which led to the team's decision to implement this technology. Factors considered include energy penalties, comfort, indoor air quality (IAQ), building shell tightness, and equipment costs. Cost benefit of heat recovery ventilation was also considered. Earlier results of the SEP team's efforts have indicated a severe ventilation problem within the schools of the United States. Two case studies are presented where HVAC technology was implemented for controlling radon concentrations. One involved the installation of a heat recovery ventilator to depressurise a crawl space and provide ventilation to the classrooms which previously had no mechanical ventilation. The other involved the restoration of a variable air volume system in a two-storey building. The HVAC system's controls were restored and modified to provide a constant building pressure differential to control the entry of radon. Pre-mitigation and post-mitigation indoor air pollutant measurements were taken, including radon, carbon dioxide (CO 2 ), particulates, and bio-aerosols. Long-term monitoring of radon, CO 2 , building pressure differentials, and indoor/outdoor temperature and relative humidity is presented. (author)

Investigating the adaptive model of thermal comfort for naturally ventilated school buildings in Taiwan

Science.gov (United States)

Hwang, Ruey-Lung; Lin, Tzu-Ping; Chen, Chen-Peng; Kuo, Nai-Jung

2009-03-01

Divergence in the acceptability to people in different regions of naturally ventilated thermal environments raises a concern over the extent to which the ASHRAE Standard 55 may be applied as a universal criterion of thermal comfort. In this study, the ASHRAE 55 adaptive model of thermal comfort was investigated for its applicability to a hot and humid climate through a long-term field survey performed in central Taiwan among local students attending 14 elementary and high schools during September to January. Adaptive behaviors, thermal neutrality, and thermal comfort zones are explored. A probit analysis of thermal acceptability responses from students was performed in place of the conventional linear regression of thermal sensation votes against operative temperature to investigate the limits of comfort zones for 90% and 80% acceptability; the corresponding comfort zones were found to occur at 20.1-28.4°C and 17.6-30.0°C, respectively. In comparison with the yearly comfort zones recommended by the adaptive model for naturally ventilated spaces in the ASHRAE Standard 55, those observed in this study differ in the lower limit for 80% acceptability, with the observed level being 1.7°C lower than the ASHRAE-recommended value. These findings can be generalized to the population of school children, thus providing information that can supplement ASHRAE Standard 55 in evaluating the thermal performance of naturally ventilated school buildings, particularly in hot-humid areas such as Taiwan.

Equivalence in Ventilation and Indoor Air Quality

Energy Technology Data Exchange (ETDEWEB)

Sherman, Max; Walker, Iain; Logue, Jennifer

2011-08-01

We ventilate buildings to provide acceptable indoor air quality (IAQ). Ventilation standards (such as American Society of Heating, Refrigerating, and Air-Conditioning Enginners [ASHRAE] Standard 62) specify minimum ventilation rates without taking into account the impact of those rates on IAQ. Innovative ventilation management is often a desirable element of reducing energy consumption or improving IAQ or comfort. Variable ventilation is one innovative strategy. To use variable ventilation in a way that meets standards, it is necessary to have a method for determining equivalence in terms of either ventilation or indoor air quality. This study develops methods to calculate either equivalent ventilation or equivalent IAQ. We demonstrate that equivalent ventilation can be used as the basis for dynamic ventilation control, reducing peak load and infiltration of outdoor contaminants. We also show that equivalent IAQ could allow some contaminants to exceed current standards if other contaminants are more stringently controlled.

(LIRNEasia) : Building Capacity in ICT Policy

International Development Research Centre (IDRC) Digital Library (Canada)

Learning Initiatives for Network Economies in Asia (LIRNEasia) : Building Capacity in ICT Policy. It is now generally accepted that affordable, effective telecommunication services play an integral role in development. Although there has been strong growth in connectivity in Asia, those who have benefited most are the urban ...

Enhancement of natural ventilation in buildings using a thermal chimney

Energy Technology Data Exchange (ETDEWEB)

Lee, Kwang Ho [University of California at Berkeley, Berkeley, CA (United States); Strand, Richard K. [University of Illinois at Urbana-Champaign, Champaign, IL (United States)

2009-06-15

A new module was developed for and implemented in the EnergyPlus program for the simulation and determination of the energy impact of thermal chimneys. This paper describes the basic concepts, assumptions, and algorithms implemented into the EnergyPlus program to predict the performance of a thermal chimney. Using the new module, the effects of the chimney height, solar absorptance of the absorber wall, solar transmittance of the glass cover and the air gap width are investigated under various conditions. Chimney height, solar absorptance and solar transmittance turned out to have more influence on the ventilation enhancement than the air gap width. The potential energy impacts of a thermal chimney under three different climate conditions are also investigated. It turned out that significant building cooling energy saving can be achieved by properly employing thermal chimneys and that they have more potential for cooling than for heating. In addition, the performance of a thermal chimney was heavily dependent on the climate of the location. (author)

Computer-simulation study on fire behaviour in the ventilated cavity of ventilated façade systems

Directory of Open Access Journals (Sweden)

Giraldo María P.

2013-11-01

Full Text Available Fire spread through the façades is widely recognized as one of the fastest pathways of fire spreading in the buildings. Fire may spread through the façade in different ways depending on the type of façade system and on the elements and materials from which it is constructed. Ventilated façades are multilayer systems whose main feature is the creation of an air chamber of circulating air between the original building wall and the external cladding. The “chimney effect” in the air cavity is a mechanism that improves the façade's thermal behaviour and avoids the appearance of moisture from rain or condensation. However, in a event of fire, it may contribute to the quickest spreading of fire, representing a significant risk to the upper floors of a building. This study deals with some aspects of fire propagation through the ventilated cavity in ventilated façade systems. Also we review the provisions stipulated by the Spanish building code (Código Técnico de la Edificación, CTE [1] to avoid fire spread outside the building. The results highlight the importance of the use of proper fire barriers to ensure the compartmentalization of the ventilated cavity, as well as the use of non-combustible thermal insulation materials, among others. In addition, based on the results, it might be considered that the measures stipulated by the CTE are insufficient to limit the risks associated with this kind of façades systems. The study has been performed using field models of computational fluid-dynamics. In particular, the Fire Dynamics Simulator (FDS software has been used to numerically solve the mathematical integration models.

Technology Solutions Case Study: Selecting Ventilation Systems for Existing Homes

Energy Technology Data Exchange (ETDEWEB)

None

2014-12-01

In multifamily buildings, particularly in the Northeast, exhaust ventilation strategies are the norm as a means of meeting both local exhaust and whole-unit mechanical ventilation rates. The issue of where the "fresh" air is coming from is gaining significance as air-tightness standards for enclosures become more stringent, and the normal leakage paths through the building envelope disappear. Researchers from the Consortium for Advanced Residential Buildings (CARB) found that the majority of high performance, new construction, multifamily housing in the Northeast use one of four general strategies for ventilation: continuous exhaust only with no designated supply or make-up air source, continuous exhaust with ducted make-up air to apartments, continuous exhaust with supply through a make-up air device integral to the unit HVAC, and continuous exhaust with supply through a passive inlet device, such as a trickle vent. Insufficient information is available to designers on how these various systems are best applied. In this project, the CARB team evaluated the four different strategies for providing make-up air to multifamily residential buildings and developed guidelines to help contractors and building owners choose the best ventilation systems.

Evaluation of Discharge Coefficients for Window Openings in Wind Driven Natural Ventilation

DEFF Research Database (Denmark)

Heiselberg, Per; Sandberg, Mats

2006-01-01

This paper describes the classical approach for calculation of wind driven airflow through large openings in buildings and discusses the fulfilment of the limiting assumptions. It is demonstrated that the limiting assumptions are not fulfilled for large openings in buildings for cross ventilation...... cannot be regarded as a constant and it is very difficult to estimate correct values resulting in less accuracy of prediction of natural ventilation.......This paper describes the classical approach for calculation of wind driven airflow through large openings in buildings and discusses the fulfilment of the limiting assumptions. It is demonstrated that the limiting assumptions are not fulfilled for large openings in buildings for cross ventilation......, and therefore, the classical approach is not appropriate for prediction of airflow through large openings in buildings in the cross ventilation case. Using the approach for real openings and estimating the discharge coefficient for window openings has also not been very successful. The discharge coefficient...

Single-sided Natural Ventilation Driven by a Combination of Wind Pressure and Temperature Difference

DEFF Research Database (Denmark)

Larsen, Tine Steen; Heiselberg, Per

2007-01-01

Natural ventilation is a commonly used principle when ventilation systems for buildings are designed. The ventilation can either be obtained by automatically controlled openings in the building envelope, or it can just be the simple action of opening a door or a window to let the fresh air in...

Comparative Policy Study for Green Buildings in U.S. and China

Energy Technology Data Exchange (ETDEWEB)

Khanna, Nina; Romankiewicz, John; Feng, Wei; Zhou, Nan; Ye, Qing

2014-04-01

Prominent barriers facing the U.S. green building industry include the fact that government bodies that supervise health, fire safety, land, and other public operations are slow to revise codes to accommodate green building (regulatory barrier). In China, the lack of a green building professional accreditation process similar to the Leadership in Energy and Environmental Design (LEED) AP process limits the green building workforce capacity development (informational barrier). The main policies highlighted in this report to tackle these barriers are 1) comprehensive codes and labeling plan (informational, institutional), 2) government-led targets and demonstrations (risk), 3) education and awareness programs (informational), 4) fiscal policy that supports green building investment (financial), and 5) integrated design promotion (institutional, financial).

Influence of staircase ventilation state on the airflow and heat transfer of the heated room on the middle floor of high rise building

International Nuclear Information System (INIS)

Shi, W.X.; Ji, J.; Sun, J.H.; Lo, S.M.; Li, L.J.; Yuan, X.Y.

2014-01-01

Highlights: • Experiments are conducted in a scaled building model. • The flow and heat transfer in the heated room are investigated. • The staircase ventilation state influence on the heated room. • The results are useful to understand the safety and energy efficiency of building. - Abstract: Safety and energy efficiency of high rise buildings have attracted public attention in recent decades. In this paper, a set of experiments was conducted in a scaled building model with 12 floors to study the influence of the staircase ventilation state on the flow and heat transfer of the heated room on the middle floor. The airflow, room temperature and fuel burning rate were investigated. It is found that when the window above the heated room is opened, the vents state below the heated room has a significant effect on the airflow and heat transfer in the heated room. When the vents below the heated room are closed, the single-directional air flows into the heated room owing to the stronger stack effect. And the flame tilt angle is larger and the upper hot smoke temperature in the heated room is low. However, when the windows above the heated room are closed, the vents state below the heated room has little influence on the airflow and heat transfer in the heated room. And, there is two-directional air flowing through the door of the heated room The burning rate of heat source is also affected by the staircase ventilation state, and the variation trend varies with the opened window position and pool size

[Biological contamination in office buildings related to ventilation/air conditioning system].

Science.gov (United States)

Bródka, Karolina; Sowiak, Małgorzata; Kozajda, Anna; Cyprowski, Marcin; Irena, Szadkowska-Stańczyk

2012-01-01

Indoor air is contaminated with microorganisms coming from both the atmospheric air and sources present in premises. The aim of this study was to analyze the concentrations of biological agents in office buildings, dependending on ventilation/air conditioning system and season. The study covered office buildings (different in the system of ventila-tion/air conditioning). Air samples for assessing the levels of inhalable dust, endotoxins and (1-->3)-beta-D-glucans, were taken at the selected stationary points of each building during summer and winter. The air was sampled for 6 h, using portable sets consisting of the GilAir 5 pump and the head filled with a filter of fiber glass. The samples for the presence of airborne bacteria and fungi were collected twice during the day using the impaction method. Average concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans in office premises were 0.09 mg/m3, 6.00 x 10(2) cfu/m3, 4.59 x 10(1) cfu/m3, 0.42 ng/m3 and 3.91 ng/m3, respectively. Higher concentrations of the investigated agents were found in summer. In premises with air conditioning concentrations of airborne fungi, (1-->3)-beta-D-glucans and inhalable dust were significantly lower in winter. In summer the trend was reverse except for (1-->3)-beta-D-glucans. Concentrations of biological agents were affected by the season and the presence of air conditioning. Concentrations of inhalable dust, bacteria, fungi, endotoxins and (1-->3)-beta-D-glucans, observed inside the office buildings, were significantly higher in summer than in winter. The presence of the air conditioning system modified in various ways the levels of biological agents. Its influence was greater on the concentration of fungi and (1-->3)-beta-D-glucans than on that of bacteria and endotoxins.

Norwegian building's energy policy: multiple and inconsistent; Norsk byggenergipolitikk: mangfoldig og inkonsistent

Energy Technology Data Exchange (ETDEWEB)

Boasson, Elin Lerum

2009-09-15

Historically, Norwegian building-construction policies have been part of the state's welfare policy. After 2000, a new conceptualisation of buildings emerged in Europe. Buildings were now regarded as a part of the energy system. The term 'energy performance of buildings' covers both the thermal quality of the building envelope and on-site energy production. In 2002 the EU developed an Energy Performance of Buildings Directive, while EU state aid regulations constrained national support schemes directed at fostering buildings with high energy performance. The building construction industry is a loosely coupled industry, and by year 2000 building construction was rather de-politicized. Although governmental regulations tend to be developed by governmental organisations and research communities in collaboration, political executives have, from time to time after year 2000, engaged directly in the development policy regarding energy performance of buildings. This report explores: 1) Why have Norwegian governments, in the period between 2000 and 2008, developed four strains of policies directed toward promoting buildings with high energy performance? 2) How did the European environment, the building construction sector (industry and governmental regulators) and the Norwegian governmental hierarchical steering intervene and shape the outcomes? (Author)

Stimulation of good building and ductwork airtightness through EPBD

DEFF Research Database (Denmark)

Guyot, Gaelle; Carrié, Remi; Schild, Peter

Building and ductwork leakage are detrimental to energy conservation, comfort, and hygiene. They can cause building damage and it can prevent proper control of the ventilation airflow rates. Through the ASIEPI project, we have identified that while some key elements for a market transformation on...... on envelope airtightness are under development in many countries, status quo seems to prevail for the duct market. With the objective of all new constructions being “nearly zero energy buildings” in 2020, policy makers need to know how better airtightness can be stimulated....

Practical guidebook on the modulation of ventilation flow rates; Guide pratique sur la modulation des debits de ventilation

Energy Technology Data Exchange (ETDEWEB)

NONE

2000-07-01

The modulation of ventilation flow rates aims at adapting the flow rate of ventilation systems to the real occupancy of rooms, at maintaining a good indoor air quality and at mastering the energy expenses due to air renewing in rooms. This technical guidebook presents the design of modulated ventilation systems (definition of occupancy areas in buildings, choice of presence sensors (CO{sub 2}, hygrometry, temperature, CO, VOC and other specific probes)), their principle and implementation. (J.S.)

High-Performance Buildings – Value, Messaging, Financial and Policy Mechanisms

Energy Technology Data Exchange (ETDEWEB)

McCabe, Molly

2011-02-22

At the request of the Pacific Northwest National Laboratory, an in-depth analysis of the rapidly evolving state of real estate investments, high-performance building technology, and interest in efficiency was conducted by HaydenTanner, LLC, for the U.S. Department of Energy (DOE) Building Technologies Program. The analysis objectives were • to evaluate the link between high-performance buildings and their market value • to identify core messaging to motivate owners, investors, financiers, and others in the real estate sector to appropriately value and deploy high-performance strategies and technologies across new and existing buildings • to summarize financial mechanisms that facilitate increased investment in these buildings. To meet these objectives, work consisted of a literature review of relevant writings, examination of existing and emergent financial and policy mechanisms, interviews with industry stakeholders, and an evaluation of the value implications through financial modeling. This report documents the analysis methodology and findings, conclusion and recommendations. Its intent is to support and inform the DOE Building Technologies Program on policy and program planning for the financing of high-performance new buildings and building retrofit projects.

Wind tunnel study of natural ventilation of building integrated photovoltaics double skin façade

Science.gov (United States)

Hudişteanu, Sebastian Valeriu; Popovici, Cătălin George; Cherecheş, Nelu-Cristian

2018-02-01

The paper presents a wind tunnel experimental analysis of a small-scale building model (1:30). The objective of the study is to determine the wind influence on the ventilation of a double skin façade channel (DSF) and the cooling effect over integrated photovoltaic panels. The tests were achieved by conceiving and implementation of an experimental program using a wind tunnel with atmospheric boundary layer. The effect of the wind over the ventilation of the horizontal channels of double skin façades is evaluated for different incident velocities. The results are generalized for the average steady state values of the velocities analysed. The experimental results put in evidence the correlation between the reference wind velocity and the dynamics of the air movement inside the double skin façade. These values are used to determine the convective heat transfer and the cooling effect of the air streams inside the channel upon the integrated photovoltaic panels. The decrease of the photovoltaic panels temperature determines a raise of 11% in efficiency and power generated.

Wind tunnel study of natural ventilation of building integrated photovoltaics double skin façade

Directory of Open Access Journals (Sweden)

Hudişteanu Sebastian Valeriu

2018-01-01

Full Text Available The paper presents a wind tunnel experimental analysis of a small-scale building model (1:30. The objective of the study is to determine the wind influence on the ventilation of a double skin façade channel (DSF and the cooling effect over integrated photovoltaic panels. The tests were achieved by conceiving and implementation of an experimental program using a wind tunnel with atmospheric boundary layer. The effect of the wind over the ventilation of the horizontal channels of double skin façades is evaluated for different incident velocities. The results are generalized for the average steady state values of the velocities analysed. The experimental results put in evidence the correlation between the reference wind velocity and the dynamics of the air movement inside the double skin façade. These values are used to determine the convective heat transfer and the cooling effect of the air streams inside the channel upon the integrated photovoltaic panels. The decrease of the photovoltaic panels temperature determines a raise of 11% in efficiency and power generated.

Improving comfort and health with personalized ventilation

DEFF Research Database (Denmark)

Melikov, Arsen Krikor

2004-01-01

The thermal environment and air quality in buildings affects occupants¿ health, comfort and performance. The heating, ventilating and air-conditioning (HVAC) of buildings today is designed to provide a uniform room environment. However, large individual differences exist between occupants in regard...... existing knowledge on performance of personalized ventilation (PV) and on human response to it. The airflow interaction in the vicinity of the human body is analysed and its impact on thermal comfort and inhaled air quality is discussed together with control strategies and the application of PV in practice...

Performance evaluation of ventilation radiators

International Nuclear Information System (INIS)

Myhren, Jonn Are; Holmberg, Sture

2013-01-01

A ventilation radiator is a combined ventilation and heat emission unit currently of interest due to its potential for increasing energy efficiency in exhaust-ventilated buildings with warm water heating. This paper presents results of performance tests of several ventilation radiator models conducted under controlled laboratory conditions. The purpose of the study was to validate results achieved by Computational Fluid Dynamics (CFD) in an earlier study and identify possible improvements in the performance of such systems. The main focus was on heat transfer from internal convection fins, but comfort and health aspects related to ventilation rates and air temperatures were also considered. The general results from the CFD simulations were confirmed; the heat output of ventilation radiators may be improved by at least 20% without sacrificing ventilation efficiency or thermal comfort. Improved thermal efficiency of ventilation radiators allows a lower supply water temperature and energy savings both for heating up and distribution of warm water in heat pumps or district heating systems. A secondary benefit is that a high ventilation rate can be maintained all year around without risk for cold draught. -- Highlights: ► Low temperature heat emitters are currently of interest due to their potential for increasing energy efficiency. ► A ventilation radiator is a combined ventilation and heat emission unit which can be adapted to low temperature heating systems. ► We examine how ventilation radiators can be made to be more efficient in terms of energy consumption and thermal comfort. ► Current work focuses on heat transfer mechanisms and convection fin configuration of ventilation radiators

Manchester Civil Justice Centre: Procuring and Managing an Institutional Building with a Mixed Mode Ventilation System—A Case for Post-Occupancy Evaluation

Directory of Open Access Journals (Sweden)

John Napier

2013-04-01

Full Text Available Manchester Civil Justice Centre is a striking contemporary 14 storey court building which has won awards for many different aspects of its design, construction and sustainability. From November 2002 to July 2005, the author was a key member of Denton Corker Marshall’s London project team having responsibility for key areas of design development, integration of technology and sustainable design including the East elevation’s “environmental veil”. This paper tracks the procurement of the building, describing its low energy features and their performance in practice. The paper reviews the low carbon elements of the design (daylight and natural ventilation systems in the context of similar buildings and the buildings operational performance. The building has a mixed mode ventilation system which is managed centrally; the paper describes the ongoing relationship between the Facilities Management and the building’s users and their expectations of comfort and offers an explanation as to why the building’s energy performance is not as good as predicted at design stage. A case is made that this building is a significant example of low energy design and would form a good example for a detailed Post Occupancy Evaluation. The energy performance of the building could be studied in more detail to encourage the users (judges, staff and the public to improve the building’s energy performance and to share knowledge within the construction industry. Institutional and commercial barriers to the more mainstream adoption of Post Occupancy Evaluation are discussed with respect to the Manchester Civil Justice Centre.

Short Term Airing by Natural Ventilation

DEFF Research Database (Denmark)

Heiselberg, Per; Perino, M.

2010-01-01

The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. Among the available ventilation strategies...... that are currently available, buoyancy driven, single-sided natural ventilation has proved to be very effective and can provide high air change rates for temperature and Indoor Air Quality (IAQ) control. However, to promote a wider distribution of these systems an improvement in the knowledge of their working...... airflow rate, ventilation efficiency, thermal comfort and dynamic temperature conditions. A suitable laboratory test rig was developed to perform extensive experimental analyses of the phenomenon under controlled and repeatable conditions. The results showed that short-term window airing is very effective...

Performance potential of mechanical ventilation systems with minimized pressure loss

DEFF Research Database (Denmark)

Terkildsen, Søren; Svendsen, Svend

2013-01-01

simulations that quantify fan power consumption, heating demand and indoor environmental conditions. The system was designed with minimal pressure loss in the duct system and heat exchanger. Also, it uses state-of-the-art components such as electrostatic precipitators, diffuse ceiling inlets and demand......In many locations mechanical ventilation has been the most widely used principle of ventilation over the last 50 years but the conventional system design must be revised to comply with future energy requirements. This paper examines the options and describes a concept for the design of mechanical...... ventilation systems with minimal pressure loss and minimal energy use. This can provide comfort ventilation and avoid overheating through increased ventilation and night cooling. Based on this concept, a test system was designed for a fictive office building and its performance was documented using building...

Dampness in buildings and health. Building characteristics as predictors for dampness in 8681 Swedish dwellings

DEFF Research Database (Denmark)

Hagerhed, L.; Bornehag, Carl-Gustaf; Sundell, Jan

2002-01-01

Questionnaire data on 8681 dwellings included in the Swedish study "Dampness in Buildings and Health" have been analysed for associations between dampness indicators, perceptions of indoor air quality and building characteristics such as time of construction, type of ventilation and type of found......Questionnaire data on 8681 dwellings included in the Swedish study "Dampness in Buildings and Health" have been analysed for associations between dampness indicators, perceptions of indoor air quality and building characteristics such as time of construction, type of ventilation and type...... of "Dry air" in 17.3 and 33.7% respectively. Older buildings and the use of natural ventilation were associated with increased frequency of dampness indicators as well as to increased frequencies of complaints on bad indoor air quality....

A CFD study for evaluating the effects of natural ventilation on indoor comfort conditions

Directory of Open Access Journals (Sweden)

Miguel Mora-Pérez

2017-03-01

Full Text Available There is an increasing interest in improving energy efficiency in buildings due to the increased awareness about environmental impact and energy cost. Natural ventilation is an environmentally friendly technique which has become more attractive way for reducing energy use while it also provides acceptable comfort conditions. The research shows a case study building in which the natural ventilation effect due to wind-driven forces on indoor comfort conditions is evaluated. Moreover, the architectural solutions selected during the building design phase to improve the natural ventilation behaviour are successfully validated in a full-scale building. The indoor comfort conditions are evaluated through contrasted performance indicators: draught risk (DR, predicted percentage of dissatisfied people (PPD and predicted mean vote (PMV indexes. The results show that air movement due to natural ventilation allows increasing indoor air temperature maintaining the initial comfort conditions. Therefore, the mechanical air conditioning use can be postponed until the indoor air temperature is high and would, consequently, reduce the total building energy consumption. Thereby, a proper natural ventilation focus during the initial design stage could improve the building energy efficiency without compromising the indoor comfort conditions.

Green buildings for Egypt: a call for an integrated policy

Science.gov (United States)

Bampou, P.

2017-11-01

As global warming is on the threshold of each country worldwide, Middle East and North African (MENA) region has already adopted energy efficiency (EE) policies on several consuming sectors. The present paper valuates the impact of temperature increase in the residential building sector of Egypt that is the most integrated example of the 7 out of the 20 MENA countries that have started their green efforts upon building environment. Furthermore, as it is based on a literature research upon socio-economic characteristics, existing building stock, existing legal and institutional framework, it elaborates a quantitative evaluation of Egypt's energy-saving potential, outlining basic constraints upon energy conservation, in order for Egypt to be able to handle the high energy needs due to its warm climate. Last but not least, the paper proposes a policy pathway for the implementation of green building codes and concludes with the best available technologies to promote EE in the Egyptian building sector.

[Optimizing antibiotics policy in the Netherlands. VI. SWAB advice: no selective decontamination of intensive care patients on mechanical ventilation

NARCIS (Netherlands)

Bonten, M.J.; Kullberg, B.J.; Filius, P.M.

2001-01-01

The Working Party on Antibiotic Policy (Dutch acronym is SWAB) has issued a guideline in which the pro and cons of the routine use of selective decontamination (SD) in patients in intensive care (IC) on mechanical ventilation are compared in order to decide whether SD is indicated. The effectiveness

Buoyancy-Driven Ventilation Generated by the Double-Skin Façade of a High-Rise Building in Tropical Climate: Case Study Bandung, Indonesia

Directory of Open Access Journals (Sweden)

Aziiz Akhlish Diinal

2017-01-01

Full Text Available High-rise buildings in tropical region is identical to the use of mechanical Air Conditioning in massive scale. Nevertheless, there is an encouragement to high-rise buildings to reduce its energy consumptions, since they consume quite large amount of energy. This challenge can be overcome with various of strategies, one of them, by means of reducing the cooling load of mechanical Air Conditioning in high-rise building. Prospects come from the modern tall building design strategies, for example the use of double-skin façade to give addition of building skin which could provide indoor temperature protection from outside. Double-skin façade system has continued to increase in buildings in a tropical region such as in Indonesia. However, there is another potential of double skin façade, which is the possibility to increase the buoyancy effect in the air gap between the skin and building envelope. The possibility needs to be studied in order to give a proper way in designing double-skin façade of a high-rise building, especially on Bandung-Indonesia tropical climate. This paper explores the potential of double-skin façade in driving the air inside the façade to generate natural ventilation for a high-rise building in Bandung climate condition. Two parameters are used in exploring the buoyancy force, the width of double-skin façade and the temperature of the skin façade. In general, double-skin façade of a high-rise building in tropical climate can generate buoyancy driven ventilation for the building, it relates strongly to the distance between of the double-skin façade and the building envelope.

Installation of ventilated facades without scaffolding in high-rise buildings

Science.gov (United States)

Gnedina, Lyubov; Muchkina, Arina; Labutin, Alexander

2018-03-01

This article consider the use of polystyrene concrete blocks during assembling enclosing structure of ventilated facades in high-rise monolithic housing construction. Comparing with traditional technology devices hinged ventilated facade the main advantage of the proposed design is an exception of using scaffold, that leads to a cheapening of the enclosing structure. Proposed solutions are confirmed by patents of the Russian Federation.

Displacement Ventilation in Hospital Environments

DEFF Research Database (Denmark)

Li, Yuguo; Nielsen, Peter V.; Sandberg, Mats

2011-01-01

Hospital differ from conventional buildings in terms of ventilation needs. Exhaled infectious droplets or droplet nuclei of an infected patient need to be removed in general wards, waiting areas and isolation rooms to minimize transmission to health-care workers, other patients and visitors. In m....... In most health-care environments, harmful microorganisms and infectious aerosols may exist in relatively high concentration. They are particularly harmful to patients due to reduced immunity, and to those with open wounds.......Hospital differ from conventional buildings in terms of ventilation needs. Exhaled infectious droplets or droplet nuclei of an infected patient need to be removed in general wards, waiting areas and isolation rooms to minimize transmission to health-care workers, other patients and visitors...

Ventilation with heat recovery

DEFF Research Database (Denmark)

Tommerup, Henrik M.; Svendsen, Svend

2005-01-01

This paper presents the experiences from the use of ventilation with heat recovery in several experimental single-family houses developed and built within the last four years to meet the new Danish energy requirements of 2005. Included are descriptions of the ventilation system components...... and the main functional demands as well as measurements of the thermal efficiency, electricity consumptions and building air tightness. The paper addresses the aspects of minimizing the heat loss from the duct system and the heat recovery unit (when placed in an unheated attic space) in order to obtain...

Environmental Noise Exposure On Occupants In Naturally Ventilated Open-Plan Offices Case Of Selected Offices In Kumasi Ghana

Directory of Open Access Journals (Sweden)

Koranteng

2015-08-01

Full Text Available The design of buildings in public educational institutions in Ghana predominantly adopts open-plan offices that are naturally ventilated with the aid of operable windows for reasons such as achieving adaptable spaces improved social climate and effective ventilation. However adoption of open-plan naturally ventilated offices in these educational institutions expose occupants to noise that emanates indoors and from outdoor sources which can interfere with and impede work performance. The study aimed at assessing noise exposure levels and occupants satisfaction with noise level in selected naturally ventilated open-plan offices in Ghana. The study employed an empirical assessment of the noise levels in and around three of the office buildings using a PCE222 Digital Sound Level Meter and a survey involving interviews to assess workers satisfaction of noise levels of the open-plan offices at the Kwame Nkrumah University of Science and Technology in Kumasi. The results show that mean outdoor noise levels for offices ranged from 11 per cent below to 5 per cent above the WHO permissible limits while mean indoor noise levels exceeded the limit by between 20-40 per cent during the course of the day. In spite of the high levels of noise occupants generally considered the overall noise level in their offices as acceptable. Likewise the results indicate that there are no significant differences in occupants exposure to noise from their various sitting positions in an office space and floor levels in an office building. The paper recommends strategies to manage and improve ambient noise quality within naturally ventilated open-plan office spaces in Ghana. The study will be of relevance as a useful guide to organizations and policy makers concerned with built environmental issues.

On analysis of operating efficiency of autonomous ventilation systems

Directory of Open Access Journals (Sweden)

Kostuganov Arman

2017-01-01

Full Text Available The paper deals with the causes and consequences of malfunctioning of natural and mechanical ventilation systems in civil buildings of Russia. Furthermore it gives their classification and analysis based on the literature review. On the basis of the analysis technical solutions for improving the efficiency of ventilation systems in civil buildings are summarized and the field of their application is specified. Among the offered technical solutions the use of autonomous ventilation systems with heat recovery is highlighted as one of the most promising and understudied. Besides it has a wide range of applications. The paper reviews and analyzes the main Russian and foreign designs of ventilation systems with heat recovery that are mostly used in practice. Three types of such systems: UVRK-50, Prana-150, ТеFо are chosen for consideration. The sequence of field tests of selected autonomous ventilation systems have been carried out in order to determine the actual air exchange and efficiency of heat recovery. The paper presents the processed results of the research on the basis of which advantages and disadvantages of the tested ventilation systems are identified and recommendations for engineering and manufacturing of new design models of autonomous ventilation systems with heat recovery are formulated.

Quantification of ventilated facade efficiency by using computational fluid mechanics techniques

International Nuclear Information System (INIS)

Mora Perez, M.; Lopez Patino, G.; Bengochea Escribano, M. A.; Lopez Jimenez, P. A.

2011-01-01

In some countries, summer over-heating is a big problem in a buildings energy balance. Ventilated facades are a useful tool when applied to building design, especially in bio climatic building design. A ventilated facade is a complex, multi-layer structural solution that enables dry installation of the covering elements. The objective of this paper is to quantify the efficiency improvement in the building thermal when this sort of facade is installed. These improvements are due to convection produced in the air gap of the facade. This convection depends on the air movement inside the gap and the heat transmission in this motion. These quantities are mathematically modelled by Computational Fluid Dynamics (CFD) techniques using a commercial code: STAR CCM+. The proposed method allows an assessment of the energy potential of the ventilated facade and its capacity for cooling. (Author) 23 refs.

Experimental and Numerical Investigation of the Tracer Gas Methodology in the Case of a Naturally Cross-Ventilated Building

DEFF Research Database (Denmark)

Nikolopoulos, Nikos; Nikolopoulos, Aristeidis; Larsen, Tine Steen

2012-01-01

The paper presents the investigation of a naturally cross – ventilated building using both experimental and numerical methods with the parameters being the free-stream and the incidence angle of the wind to the openings of the building. The experimental methodology calculates the air change rate......, focusing on the time dependent character of the induced flow field. The numerical results are compared with corresponding experimental data for the three aforementioned experimental methodologies in the case of a full scale building inside a wind-tunnel. The numerical investigation reveals that for large...... based either on measurements of the inlet velocity profile, the outlet velocity profile or the descending rate of the tracer gas concentration using the decay method. The numerical investigation is based on the solution of the governing Navier-Stokes equations in their full three dimensional expression...

Light and Ventilation Analysis for Infrastructure in an Urban Region - A Case Study

Directory of Open Access Journals (Sweden)

Awkash Kumar

2017-07-01

Full Text Available Pressure on infrastructure due to over population has deteriorated the indoor environment causing various health issues. It has also contributed to the sick building syndrome making huge monetary burden to economy. Public health department of the country has taken many actions to mitigate these issues however; design of the building was not taken into consideration. Optimum quantities of light and proper ventilation express the quality of indoor environment. Also, the use of natural light and ventilation is definitely an advantage with the raising concerns regarding the cost and environmental impact of energy use. Natural light and ventilation can reduce building construction and operation costs and reduce the energy consumption. Moreover it would also ensure safe, healthy and comfortable living conditions. Therefore, it is very important to assess indoor environment before implementing new construction or building. This provides theoretical guidelines and basic calculations for understanding a green infrastructures and the factors related to it. In this paper, a building has been studied in an urban city of India where the percentage area of light and ventilation were analyzed Analysis showed the percentage of light is thrice and ventilation is twice the prescribed limits by Indian Green Building Council (IGBC. It has been found that building under study fulfills the given criteria by IGBC. This analysis can be useful while constructing a new infrastructure to improve the standard of living as 90% time is spent indoors.

Ventilation System Effectiveness and Tested Indoor Air Quality Impacts

Energy Technology Data Exchange (ETDEWEB)

Rudd, Armin [National Renewable Energy Lab. (NREL), Golden, CO (United States); Bergey, Daniel [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2014-02-01

Ventilation system effectiveness testing was conducted at two unoccupied, single-family, detached lab homes at the University of Texas - Tyler. Five ventilation system tests were conducted with various whole-building ventilation systems. Multizone fan pressurization testing characterized building and zone enclosure leakage. PFT testing showed multizone air change rates and interzonal airflow. Cumulative particle counts for six particle sizes, and formaldehyde and other Top 20 VOC concentrations were measured in multiple zones. The testing showed that single-point exhaust ventilation was inferior as a whole-house ventilation strategy. It was inferior because the source of outside air was not direct from outside, the ventilation air was not distributed, and no provision existed for air filtration. Indoor air recirculation by a central air distribution system can help improve the exhaust ventilation system by way of air mixing and filtration. In contrast, the supply and balanced ventilation systems showed that there is a significant benefit to drawing outside air from a known outside location, and filtering and distributing that air. Compared to the Exhaust systems, the CFIS and ERV systems showed better ventilation air distribution and lower concentrations of particulates, formaldehyde and other VOCs. System improvement percentages were estimated based on four System Factor Categories: Balance, Distribution, Outside Air Source, and Recirculation Filtration. Recommended System Factors could be applied to reduce ventilation fan airflow rates relative to ASHRAE Standard 62.2 to save energy and reduce moisture control risk in humid climates. HVAC energy savings were predicted to be 8-10%, or $50-$75/year.

Energy Analysis of the Ductless Personalized Ventilation

DEFF Research Database (Denmark)

Lelong, Cyril; Dalewski, Mariusz; Melikov, Arsen Krikor

2013-01-01

energy efficient strategies for implantation of DPV in practice. The impact of using DPV on annual energy use has been studied for different occupancy profiles in cold climates. The results suggest that using DPV combined with displacement ventilation may significantly reduce building energy use while......This study explores the impact of different occupancy profiles on the potential energy savings due to using ductless personalized ventilation (DPV) combined with displacement ventilation. Energy simulations were performed with the dynamic simulation software IDA-ICE in order to investigate optimal...

Natural ventilation: it's as easy as opening the windows, or is it

Energy Technology Data Exchange (ETDEWEB)

Siebein, G.W.

1984-10-01

The research consisted of an evaluation of the existing technologies available for passive cooling with an emphasis on strategies related to the use of natural ventilation. A preliminary data base for the study was established by three major efforts: 1. An extensive literature search of the architectural press was undertaken to ascertain the degree to which passive cooling strategies in general and natural ventilation in particular are designed into buildings at the present time. 2. An investigation of existing building stock profiles was undertaken to identify the existing and potential obstacles or advantages to the implementation of natural ventilation as a passive cooling strategy. The EIA Nonresidential Buildings Energy Consumption Survey and two previous PNL studies were reviewed. 3. Components 1 and 2 were followed up with telephone interviews and site visits with the architects, building owners and operators of selected buildings from 1 and 2 above to gain more specific insights into the problems and pleasures typically associated with natural ventilation.

Wind-induced single-sided natural ventilation in buildings near a long street canyon: CFD evaluation of street configuration and envelope design

DEFF Research Database (Denmark)

Ai, Z.T.; Mak, C.M.

2018-01-01

an urban context, this study investigates the wind-induced single-sided natural ventilation in buildings near a long street canyon under a perpendicular wind direction using CFD method. Four aspect ratios (AR) of the street canyon, from 1.0, 2.0, 4.0 to 6.0, are investigated to examine the influence...

Controlled ventilation in gas-heated low-energy houses. Primary energy savings in regard to the users behaviour

International Nuclear Information System (INIS)

Luedemann, B.; Schmitz, G.

1999-01-01

With the introduction of the energy savings regulation in Germany (ESVO) low-energy buildings will be the standard for new buildings at the turn of the millennium. The heating energy demand will sink around 30 % facing the actual standard. Systems for controlled Ventilation with heat-recovery are often regarded as an essential component to achieve the low-energy standard for buildings. The quota of the ventilation losses in high insulated buildings is up to far over 50 % of the heating energy demand. However, in practice ventilation systems often do not achieve the calculated energy-savings on the heat requirement. Until now, both technical defects of ventilation systems and the tightness of buildings are at the centre of discussion dealing with this problem. Therefore, in a common research project of three gas supply companies, an electricity distribution company and the Department of Technical Thermodynamics at the TUHH, the bandwidth of the possible energy-savings by ventilation systems with heat recovery was investigated by dynamic simulation of the thermal behaviour of buildings and ventilation systems. Above all, the question of the influence of the user behaviour was at the centre of attention. (author)

Energy efficient ventilation based on demand humidity control. Demonstration project with 49 apartments in Soenderborg

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-09-01

The aim of the project is to demonstrate how the overall energy consumption in apartment buildings can be reduced through a combination of: 1) Energy efficient ventilation based on demand humidity control; 2) Energy efficient design of the building shell including passive solar and seasonally flexible sunspaces; 3) Use of low temperature heating system. The 3 blocks in the project, each with 16 apartments, are furnished with 3 different ventilation systems: 1) Standard exhaust system according to building codes; 2) Ventilation system with humidity control. Each room is furnished with an air inlet valve controlled by a processor, which monitors the humidity; 3) Standard ventilation system with heat recovery. (au)

Energy Savings Modeling and Inspection Guidelines for Commercial Building Federal Tax Deductions for Buildings in 2016 and Later

Energy Technology Data Exchange (ETDEWEB)

Deru, Michael [National Renewable Energy Lab. (NREL), Golden, CO (United States); Field-Macumber, Kristin [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-09-01

This document provides guidance for modeling and inspecting energy-efficient property in commercial buildings for certification of the energy and power cost savings related to Section 179D of the Internal Revenue Code (IRC) enacted in Section 1331 of the 2005 Energy Policy Act (EPAct) of 2005, noted in Internal Revenue Service (IRS) Notices 2006-52 (IRS 2006), 2008-40 (IRS 2008) and 2012-26 (IRS 2012), and updated by the Protecting Americans from Tax Hikes (PATH) Act of 2015. Specifically, Section 179D provides federal tax deductions for energy-efficient property related to a commercial building's envelope; interior lighting; heating, ventilating, and air conditioning (HVAC); and service hot water (SHW) systems. This document applies to buildings placed in service on or after January 1, 2016.

Probabilistic Analysis Methods for Hybrid Ventilation

DEFF Research Database (Denmark)

Brohus, Henrik; Frier, Christian; Heiselberg, Per

This paper discusses a general approach for the application of probabilistic analysis methods in the design of ventilation systems. The aims and scope of probabilistic versus deterministic methods are addressed with special emphasis on hybrid ventilation systems. A preliminary application...... of stochastic differential equations is presented comprising a general heat balance for an arbitrary number of loads and zones in a building to determine the thermal behaviour under random conditions....

The effect of combining a relative-humidity-sensitive ventilation system with the moisture-buffering capacity of materials on indoor climate and energy efficiency of buildings

Energy Technology Data Exchange (ETDEWEB)

Woloszyn, Monika [Universite de Lyon, Lyon F-69003 (France); Universite Lyon1, Villeurbanne F-69622 (France); INSA-Lyon, CETHIL UMR CNRS 5008, bat. Sadi Carnot, F-69621 Villeurbanne cedex (France); Kalamees, Targo [Chair of Building Physics and Architecture, Tallinn University of Technology, Ehiteja tee 5 19086 (Estonia); Olivier Abadie, Marc [Pontifical Catholic University of Parana - PUCPR/CCET-Thermal Systems Laboratory, Rua Imaculada Conceicao, 1155 Curitiba, PR 80215-901 (Brazil); LEPTIAB-University of La Rochelle, Avenue M. Crepeau, 17000 La Rochelle (France); Steeman, Marijke [Department of Architecture and Urban Planning, UGENT-Ghent University, J. Plateaustraat 22, 9000 Ghent (Belgium); Sasic Kalagasidis, Angela [Department of Building Technology, Chalmers University of Technology, Sven Hultins gata 8, 412 96 Gothenburg (Sweden)

2009-03-15

Indoor moisture management, which means keeping the indoor relative humidity (RH) at correct levels, is very important for whole building performance in terms of indoor air quality (IAQ), energy performance and durability of the building. In this study, the effect of combining a relative-humidity-sensitive (RHS) ventilation system with indoor moisture buffering materials was investigated. Four comprehensive heat-air-moisture (HAM) simulation tools were used to analyse the performance of different moisture management strategies in terms of IAQ and of energy efficiency. Despite some differences in results, a good agreement was found and similar trends were detected from the results, using the four different simulation tools. The results from simulations demonstrate that RHS ventilation reduces the spread between the minimum and maximum values of the RH in the indoor air and generates energy savings. Energy savings are achieved while keeping the RH at target level, not allowing for possible risk of condensations. The disadvantage of this type of demand controlled-ventilation is that other pollutants (such as CO{sub 2}) may exceed target values. This study also confirmed that the use of moisture-buffering materials is a very efficient way to reduce the amplitude of daily moisture variations. It was possible, by the combined effect of ventilation and wood as buffering material, to keep the indoor RH at a very stable level. (author)

Green buildings in Malaysia towards greener environment: challenges for policy makers

Science.gov (United States)

Suhaida, M. S.; Tan, K. L.; Leong, Y. P.

2013-06-01

The launch of the National Green Technology Policy (NGTP) in 2009 is a manifesto of the government's seriousness in implementing "green" initiatives for the country. Specifically for buildings, the government promotes the application of renewable energy (RE) and energy efficiency (EE) and the application of green building index. With the introduction of Low Carbon Cities Framework, Green Pass, Green Neighbourhood, Green Building Index by various agencies and organisations in Malaysia, it is time to look back and see how all these tools could come together. This paper attempts to identify the challenges in harmonising the green initiatives for policy makers toward greener environment for sustainability.

Particle deposition in ventilation ducts

Energy Technology Data Exchange (ETDEWEB)

Sippola, Mark Raymond [Univ. of California, Berkeley, CA (United States)

2002-09-01

Exposure to airborne particles is detrimental to human health and indoor exposures dominate total exposures for most people. The accidental or intentional release of aerosolized chemical and biological agents within or near a building can lead to exposures of building occupants to hazardous agents and costly building remediation. Particle deposition in heating, ventilation and air-conditioning (HVAC) systems may significantly influence exposures to particles indoors, diminish HVAC performance and lead to secondary pollutant release within buildings. This dissertation advances the understanding of particle behavior in HVAC systems and the fates of indoor particles by means of experiments and modeling. Laboratory experiments were conducted to quantify particle deposition rates in horizontal ventilation ducts using real HVAC materials. Particle deposition experiments were conducted in steel and internally insulated ducts at air speeds typically found in ventilation ducts, 2-9 m/s. Behaviors of monodisperse particles with diameters in the size range 1-16 μm were investigated. Deposition rates were measured in straight ducts with a fully developed turbulent flow profile, straight ducts with a developing turbulent flow profile, in duct bends and at S-connector pieces located at duct junctions. In straight ducts with fully developed turbulence, experiments showed deposition rates to be highest at duct floors, intermediate at duct walls, and lowest at duct ceilings. Deposition rates to a given surface increased with an increase in particle size or air speed. Deposition was much higher in internally insulated ducts than in uninsulated steel ducts. In most cases, deposition in straight ducts with developing turbulence, in duct bends and at S-connectors at duct junctions was higher than in straight ducts with fully developed turbulence. Measured deposition rates were generally higher than predicted by published models. A model incorporating empirical equations based on the

EVALUATION TOOL OF CLIMATE POTENTIAL FOR VENTILATIVE COOLING

DEFF Research Database (Denmark)

Belleri, Annamaria; Psomas, Theofanis Ch.; Heiselberg, Per Kvols

2015-01-01

. Within IEA Annex 62 project, national experts are working on the development of a climate evaluation tool, which aims at assessing the potential of ventilative cooling by taking into account also building envelope thermal properties, internal gains and ventilation needs. The analysis is based on a single......-zone thermal model applied to user-input climatic data on hourly basis. The tool identifies the percentage of hours when natural ventilation can be exploited to assure minimum air change rates required by state of the art research, standards and regulations and the percentage of hours when direct ventilative...

Energy and IAQ Implications of Residential Ventilation Cooling

Energy Technology Data Exchange (ETDEWEB)

Turner, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2014-08-01

This study evaluates the energy, humidity and indoor air quality (IAQ) implications of residential ventilation cooling in all U.S. IECC climate zones. A computer modeling approach was adopted, using an advanced residential building simulation tool with airflow, energy and humidity models. An economizer (large supply fan) was simulated to provide ventilation cooling while outdoor air temperatures were lower than indoor air temperatures (typically at night). The simulations were performed for a full year using one-minute time steps to allow for scheduling of ventilation systems and to account for interactions between ventilation and heating/cooling systems.

Potential of Natural Ventilation in Shopping Centres

DEFF Research Database (Denmark)

Diederichsen, Alice; Friis, Kristina; Brohus, Henrik

2008-01-01

The indoor environmental quality (IEQ) is a fundamental requirement for a well performing shopping centre. This paper contains a pilot study of the potential of using hybrid ventilation (a combination of automatically controlled natural and mechanical ventilation - respectively NV and MV) in shop......The indoor environmental quality (IEQ) is a fundamental requirement for a well performing shopping centre. This paper contains a pilot study of the potential of using hybrid ventilation (a combination of automatically controlled natural and mechanical ventilation - respectively NV and MV......) in shopping centres with focus on both the achieved IEQ and energy consumptions for air movement. By thermal building simulations it is found that there exists an interesting potential for hybrid ventilation of shopping centres, which can lead to great savings in the electrical energy consumptions...

Demand controlled ventilation for multi-family dwellings

DEFF Research Database (Denmark)

Mortensen, Dorthe Kragsig

for centrally balanced DCV systems with heat recovery. A design expected to fulfill this requirement was investigated in detail with regard to its electricity consumption by evaluating a control strategy that resets the static pressure set point at part load. The results showed that this control strategy can......The present thesis “Demand controlled ventilation for multi-family dwellings” constitutes the summary of a three year project period during which demand specification and system design of demand controlled ventilation for residential buildings were studied. Most standards and buildings codes...... can be reduced compared to a system with constant air flow. A literature study on indoor pollutants in homes, their sources and their impact on humans formed the basis for the demand specification. Emission of pollutants in residential buildings roughly fall into constantly emitted background sources...

Achieving Natural and Hybrid Ventilation in Practice

DEFF Research Database (Denmark)

Liddament, Martin; Axley, James; Heiselberg, Per

2006-01-01

Case studies provide essential evidence about the performance of buildings. They also illustrate the methods by which a technology can be implemented as well as highlighting problems. Various case study buildings (both new and retrofit) that incorporate mixed mode, natural ventilation and low ene...

Building policy capacities: an interactive approach for linking knowledge to action in health promotion.

Science.gov (United States)

Rütten, Alfred; Gelius, Peter

2014-09-01

This article outlines a theoretical framework for an interactive, research-driven approach to building policy capacities in health promotion. First, it illustrates how two important issues in the recent public health debate, capacity building and linking scientific knowledge to policy action, are connected to each other theoretically. It then introduces an international study on an interactive approach to capacity building in health promotion policy. The approach combines the ADEPT model of policy capacities with a co-operative planning process to foster the exchange of knowledge between policy-makers and researchers, thus improving intra- and inter-organizational capacities. A regional-level physical activity promotion project involving governmental and public-law institutions, NGOs and university researchers serves as a case study to illustrate the potential of the approach for capacity building. Analysis and comparison with a similar local-level project indicate that the approach provides an effective means of linking scientific knowledge to policy action and to planning concrete measures for capacity building in health promotion, but that it requires sufficiently long timelines and adequate resources to achieve adequate implementation and sustainability. © The Author (2013). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

76 FR 65511 - Office of Governmentwide Policy; Office of Federal High-Performance Green Buildings; the Green...

Science.gov (United States)

2011-10-21

... Governmentwide Policy; Office of Federal High- Performance Green Buildings; the Green Building Advisory Committee... meeting of the Green Building Advisory Committee Meeting (the Committee). The meeting is open to the..., Office of Federal High-Performance Green Buildings, Office of Governmentwide Policy, General Services...

Short-term airing by natural ventilation - implication on IAQ and thermal comfort.

Science.gov (United States)

Heiselberg, P; Perino, M

2010-04-01

The need to improve the energy efficiency of buildings requires new and more efficient ventilation systems. It has been demonstrated that innovative operating concepts that make use of natural ventilation seem to be more appreciated by occupants. Among the available ventilation strategies that are currently available, buoyancy driven, single-sided natural ventilation has proved to be very effective and can provide high air change rates for temperature and Indoor Air Quality (IAQ) control. However, to promote a wider distribution of these systems an improvement in the knowledge of their working principles is necessary. The present study analyses and presents the results of an experimental evaluation of airing performance in terms of ventilation characteristics, IAQ and thermal comfort. It includes investigations of the consequences of opening time, opening frequency, opening area and expected airflow rate, ventilation efficiency, thermal comfort and dynamic temperature conditions. A suitable laboratory test rig was developed to perform extensive experimental analyses of the phenomenon under controlled and repeatable conditions. The results showed that short-term window airing is very effective and can provide both acceptable IAQ and thermal comfort conditions in buildings. Practical Implications This study gives the necessary background and in-depth knowledge of the performance of window airing by single-sided natural ventilation necessary for the development of control strategies for window airing (length of opening period and opening frequency) for optimum IAQ and thermal comfort in naturally ventilated buildings.

ASHRAE and residential ventilation

Energy Technology Data Exchange (ETDEWEB)

Sherman, Max H.

2003-10-01

In the last quarter of a century, the western world has become increasingly aware of environmental threats to health and safety. During this period, people psychologically retreated away from outdoors hazards such as pesticides, smog, lead, oil spills, and dioxin to the seeming security of their homes. However, the indoor environment may not be healthier than the outdoor environment, as has become more apparent over the past few years with issues such as mold, formaldehyde, and sick-building syndrome. While the built human environment has changed substantially over the past 10,000 years, human biology has not; poor indoor air quality creates health risks and can be uncomfortable. The human race has found, over time, that it is essential to manage the indoor environments of their homes. ASHRAE has long been in the business of ventilation, but most of the focus of that effort has been in the area of commercial and institutional buildings. Residential ventilation was traditionally not a major concern because it was felt that, between operable windows and envelope leakage, people were getting enough outside air in their homes. In the quarter of a century since the first oil shock, houses have gotten much more energy efficient. At the same time, the kinds of materials and functions in houses changed in character in response to people's needs. People became more environmentally conscious and aware not only about the resources they were consuming but about the environment in which they lived. All of these factors contributed to an increasing level of public concern about residential indoor air quality and ventilation. Where once there was an easy feeling about the residential indoor environment, there is now a desire to define levels of acceptability and performance. Many institutions--both public and private--have interests in Indoor Air Quality (IAQ), but ASHRAE, as the professional society that has had ventilation as part of its mission for over 100 years, is the

The influence of ventilation on moisture conditions in facades with wooden cladding

DEFF Research Database (Denmark)

Hansen, Ernst Jan de Place; Brandt, Erik

2009-01-01

A ventilated cavity behind the cladding of timber frame walls is often considered good building practice that facilitates the removal of moisture from the construction. However, moisture will only be removed from the construction by ventilating it with dry air, whereas ventilating with humid air...... might add moisture to the construction. Full-size wall elements with wooden cladding placed in a test building were exposed to natural climate on the outside and to a humid indoor climate on the inside. Temperature and moisture conditions inside the wall elements and climate parameters were monitored...

Reducing the ingress of urban noise through natural ventilation openings.

Science.gov (United States)

Oldham, D J; de Salis, M H; Sharples, S

2004-01-01

For buildings in busy urban areas affected by high levels of road traffic noise the potential to use natural ventilation can be limited by excessive noise entering through ventilation openings. This paper is concerned with techniques to reduce noise ingress into naturally ventilated buildings while minimizing airflow path resistance. A combined experimental and theoretical approach to the interaction of airflow and sound transmission through ventilators for natural ventilation applications is described. A key element of the investigation has been the development of testing facilities capable of measuring the airflow and sound transmission losses for a range of ventilation noise control strategies. It is demonstrated that a combination of sound reduction mechanisms -- one covering low frequency sound and another covering high frequency sound -- is required to attenuate effectively noise from typical urban sources. A method is proposed for quantifying the acoustic performance of different strategies to enable comparisons and informed decisions to be made leading to the possibility of a design methodology for optimizing the ventilation and acoustic performance of different strategies. The need for employing techniques for combating low frequency sound in tandem with techniques for reducing high frequency sound in reducing the ingress of noise from urban sources such as road traffic to acceptable levels is demonstrated. A technique is proposed for enabling the acoustic and airflow performance of apertures for natural ventilation systems to be designed simultaneously.

Estimation of Airflow in livestock Buildings

DEFF Research Database (Denmark)

Larsen, Rasmus

1995-01-01

The well-being of the animals (e.g. pigs) in livestock buildings is contingent on adequate ventilation. Depending on the construction of the ventilation system draught may be introduced into the buildings. Obviously this is an unwanted effect, that might lead to decreasing growth of and increasing...

Low resource ventilation unit. Preface to the final report; Ressourcebesparende ventilationsenhed. Forord til afslutningsrapport

Energy Technology Data Exchange (ETDEWEB)

Lundehoej, M.; Boersting, J.

2012-07-01

In the project a resource-saving ventilation device was developed which is based on the use of a regenerator and a reversible air flow. The regenerator is placed in the building envelope, and the concept works in the way that the heat in the air during ventilation is stored in the regenerator and brought back into the building by a reversible air change. The heated air is blown from inside the building out through the regenerator. In this way the regenerator accumulates the heat in the air. Over a period of 30-120 seconds, the regenerator capacity is utilized. When the regenerator cannot be further heated, the air flow is reversed and there is now blown cold air through the regenerator. Thereby the heat from the regenerator is released to the cold fresh air. Thus, the fresh air brings heat back into the building, whereby the air is replaced with a limited heat loss. Ventilation with a regenerator is described as micro-ventilation. (LN)

City ventilation of Hong Kong at no-wind conditions

Science.gov (United States)

Yang, Lina; Li, Yuguo

We hypothesize that city ventilation due to both thermally-driven mountain slope flows and building surface flows is important in removing ambient airborne pollutants in the high-rise dense city Hong Kong at no-wind conditions. Both spatial and temporal urban surface temperature profiles are an important boundary condition for studying city ventilation by thermal buoyancy. Field measurements were carried out to investigate the diurnal thermal behavior of urban surfaces (mountain slopes, and building exterior walls and roofs) in Hong Kong by using the infrared thermography. The maximum urban surface temperature was measured in the early noon hours (14:00-15:00 h) and the minimum temperature was observed just before sunrise (5:00 h). The vertical surface temperature of the building exterior wall was found to increase with height at daytime and the opposite occurred at nighttime. The solar radiation and the physical properties of the various urban surfaces were found to be important factors affecting the surface thermal behaviors. The temperature difference between the measured maximum and minimum surface temperatures of the four selected exterior walls can be at the highest of 16.7 °C in the early afternoon hours (15:00 h). Based on the measured surface temperatures, the ventilation rate due to thermal buoyancy-induced wall surface flows of buildings and mountain slope winds were estimated through an integral analysis of the natural convection flow over a flat surface. At no-wind conditions, the total air change rate by the building wall flows (2-4 ACH) was found to be 2-4 times greater than that by the slope flows due to mountain surface (1 ACH) due to larger building exterior surface areas and temperature differences with surrounding air. The results provide useful insights into the ventilation of a high-rise dense city at no-wind conditions.

Building Land Information Policies

DEFF Research Database (Denmark)

Enemark, Stig

2004-01-01

The paper presents a conceptual understanding in the areas of Cadastre, Land Administration, and Land Management as a basis for building adequate land information policies. To develop this understanding the paper looks at each area as a system or an infrastructure designed for handling specific...... of measurement science, spatial information, management, and land management. (2) To establish national professional associations which accommodate a modern interdisciplinary profile. (3) To assess the capacity needs in land administration and to develop the capacity needed at societal, institutional...... and personal level.    (4) To establish appropriate institutional and organisational infrastructures to manage the integration of topographic mapping and cadastral information into a coherent land administration system for sustainable development. The paper aims to establish the basic understanding for dealing...

Particle deposition from turbulent flow: Review of published research and its applicability to ventilation ducts in commercial buildings

Energy Technology Data Exchange (ETDEWEB)

Sippola, Mark R.; Nazaroff, William W.

2002-06-01

This report reviews published experimental and theoretical investigations of particle deposition from turbulent flows and considers the applicability of this body of work to the specific case of particle deposition from flows in the ducts of heating, ventilating and air conditioning (HVAC) systems. Particle deposition can detrimentally affect the performance of HVAC systems and it influences the exposure of building occupants to a variety of air pollutants. The first section of this report describes the types of HVAC systems under consideration and discusses the components, materials and operating parameters commonly found in these systems. The second section reviews published experimental investigations of particle deposition rates from turbulent flows and considers the ramifications of the experimental evidence with respect to HVAC ducts. The third section considers the structure of turbulent airflows in ventilation ducts with a particular emphasis on turbulence investigations that have been used as a basis for particle deposition models. The final section reviews published literature on predicting particle deposition rates from turbulent flows.

African Health Economics and Policy Research Capacity Building ...

International Development Research Centre (IDRC) Digital Library (Canada)

African Health Economics and Policy Research Capacity Building and Dissemination. As African countries move toward universal health coverage, it is clear there is a shortage of African experts with applied research skills in health financing such as fiscal space analysis, needs-based resource allocation methods, and ...

Experimental Study of Wind-Opposed Buoyancy-Driven Natural Ventilation

OpenAIRE

Andersen, A.; Bjerre, M.; Chen, Z. D.; Heiselberg, Per; Li, Y.

2000-01-01

Natural ventilation driven by natural forces, i.e. wind and thermal buoyancy, is an environmentally friendly system for buildings and has been increasingly used around the world in recent years to mitigate the impact on the global environment due to the significant energy consumption by heating, ventilation and air-conditioning (HV AC). There is a need for the understanding and development of theories and tools related to the design, operation and control of natural ventilation systems.

Experimental Study of Wind-Opposed Buoyancy-Driven Natural Ventilation

DEFF Research Database (Denmark)

Andersen, A.; Bjerre, M.; Chen, Z. D.

Natural ventilation driven by natural forces, i.e. wind and thermal buoyancy, is an environmentally friendly system for buildings and has been increasingly used around the world in recent years to mitigate the impact on the global environment due to the significant energy consumption by heating......, ventilation and air-conditioning (HV AC). There is a need for the understanding and development of theories and tools related to the design, operation and control of natural ventilation systems....

Performance of personalized ventilation combined with chilled ceiling in an office room: inhaled air quality and contaminant distribution

DEFF Research Database (Denmark)

Lipczynska, Aleksandra; Kaczmarczyk, Jan; Melikov, Arsen Krikor

2014-01-01

people (exhaled air, bioeffluents) and building materials (wall painting). Personalized ventilation combined with chilled ceiling ensured highest air quality at the workstation under all conditions. Pollutant concentration in the occupied zone away from the workstations did not differ substantially...... between the tested systems. Chilled ceiling combined with personalized ventilation working as the only air supplying system may be optimal solution in many buildings.......In a simulated two persons’ office room inhaled air quality and contaminant distribution provided with personalized ventilation combined with chilled ceiling, mixing ventilation only, chilled ceiling with mixing ventilation and chilled ceiling with mixing and personalized ventilation was studied...

An Attempt to Design a Naturally Ventilated Tower in Subtropical Climate of the Developing Country; Pakistan

Directory of Open Access Journals (Sweden)

Sohail Maha

2017-12-01

Full Text Available A large proportion of the world’s population resides in developing countries where there is a lack of rigorous studies in designing energy efficient buildings. This study is a step in designing a naturally ventilated high rise residential building in a tropical climatic context of the developing country, Pakistan. Karachi, the largest city of Pakistan, lies in the subtropical hot desert region with constant high temperature of average 32 °C throughout the summer and no particular winter season. The Design Builder software package is used to design a 25 storey high rise residential building relying primarily on natural ventilation. A final conceptual design is proposed after optimization of massing, geometry, orientation, and improved building envelope design including extensive shading devices in the form of trees. It has been observed that a reduction of 8 °C in indoor ambient temperature is possible to achieve with passive measures and use of night time ventilation. A fully naturally ventilated building can reduce the energy consumption for cooling and heating by 96 % compared to a building using air conditioning systems.

An Attempt to Design a Naturally Ventilated Tower in Subtropical Climate of the Developing Country; Pakistan

Science.gov (United States)

Sohail, Maha

2017-12-01

A large proportion of the world's population resides in developing countries where there is a lack of rigorous studies in designing energy efficient buildings. This study is a step in designing a naturally ventilated high rise residential building in a tropical climatic context of the developing country, Pakistan. Karachi, the largest city of Pakistan, lies in the subtropical hot desert region with constant high temperature of average 32 °C throughout the summer and no particular winter season. The Design Builder software package is used to design a 25 storey high rise residential building relying primarily on natural ventilation. A final conceptual design is proposed after optimization of massing, geometry, orientation, and improved building envelope design including extensive shading devices in the form of trees. It has been observed that a reduction of 8 °C in indoor ambient temperature is possible to achieve with passive measures and use of night time ventilation. A fully naturally ventilated building can reduce the energy consumption for cooling and heating by 96 % compared to a building using air conditioning systems.

Energy impact of indoor environmental policy for air-conditioned offices of Hong Kong

International Nuclear Information System (INIS)

Wong, L.T.; Mui, K.W.; Shi, K.L.

2008-01-01

Air-conditioned office buildings are one of the biggest energy consumers of electricity in developed cities in the subtropical climate regions. A good energy policy for the indoor environment should respond to both the needs of energy conservation and the needs for a desirable indoor healthy environment with a reduction in carbon dioxide (CO 2 ) generation. This study evaluates energy implications and the corresponding CO 2 generation of some indoor environmental policies for air-conditioned office buildings in the subtropical climate. In particular, the thermal energy consumption in an air-conditioned office building was evaluated by the heat gains through the building fabric, the transport of outdoor fresh air for ventilation, and the heat generated by the occupant and equipment in the space. With the Monte-Carlo sampling technique and the parameters from the existing office building stocks of Hong Kong, the energy consumption profiles of air-conditioned office buildings in Hong Kong were evaluated. Energy consumption profiles were simulated for certain indoor environmental quality (IEQ) policies on indoor air temperature and CO 2 concentration settings in the offices, with other building parameters remaining unchanged. The impact assessment and the regression models described in this study may be useful for evaluation of energy performances of IEQ policies. They will also be useful for the promotion of energy-saving measures in air-conditioned office buildings in Hong Kong. This study presented a useful source of references for policymakers, building professionals and end users to quantify the energy and environmental impacts due to an IEQ policy for air-conditioned office buildings

Sensory evaluation of the air in 14 office buildings

DEFF Research Database (Denmark)

Pejtersen, Jan; Schwab, R.; Mayer, E.

1999-01-01

The perceived air quality was assessed in eight mechanically and six naturally ventilated office buildings. On average, 44 offices were investigated in each building. A panel of 11 trained subjects assessed the perceived air quality in the spaces directly in the sensory unit decipol. The average...... perceived air quality in the 14 office buildings ranged from 3.4 to 7.8 decipol. The perceived air quality averaged 4.1 decipol in the mechanically ventilated buildings and 6.0 decipol in the naturally ventilated buildings. Within the buildings there was a large variation in perceived air quality between...... the offices. The results indicate that the occupants' behaviour is important for the pollution load and the air quality in offices....

Ventilation effectiveness : health benefits of heat recovery ventilators

Energy Technology Data Exchange (ETDEWEB)

Anon.

2010-08-15

Studies have shown that the installation of a heat recovery ventilator (HRV) in homes in northern Canada could improve indoor air quality and the respiratory health of inhabitants. Low ventilation rates are common in many homes in the North because the climate is severe, homes are smaller and lack basements, and occupancies are higher, leading to unhealthy indoor air quality. Northern communities also have a high rate of respiratory infections. HRVs recover much of the energy used to ventilate, which is desirable in cold regions with high heating costs. For the study, the test sample was divided into two types of houses, notably houses with active HRVs and those with control HRVs that were installed and operated but that did not function. The study results showed that HRVs provided increased ventilation. Complaints by residents about HRV noise, discomfort, or low humidity were common but equally spread between those with active and placebo HRVs. The study showed that the system design needs to be improved to better suit the needs of Inuit families. The nature of northern housing presents installation and maintenance challenges. It is hard to retrofit HRV ducting inside small, existing houses, and building supplies arrive infrequently, so detailed planning and careful take-offs of all supplies and materials must be done well in advance of construction. In addition, contractors are hard to locate and have variable expertise, and there is little technical follow-up. Robust technical support by local contractors and housing authorities is therefore important. 2 refs.

Role of ventilation in airborne transmission of infectious agents in the built environment - a multidisciplinary systematic review

DEFF Research Database (Denmark)

Li, Yiping; Leung, G.M.; Tang, J.W.

2007-01-01

There have been few recent studies demonstrating a definitive association between the transmission of airborne infections and the ventilation of buildings. The severe acute respiratory syndrome (SARS) epidemic in 2003 and current concerns about the risk of an avian influenza (H5N1) pandemic, have...... of microbiology, medicine, epidemiology, indoor air quality, building ventilation, etc. Most panel members had experience with research into the 2003 SARS epidemic. The panel systematically assessed 40 original studies through both individual assessment and a 2-day face-to-face consensus meeting. Ten of 40...... studies reviewed were considered to be conclusive with regard to the association between building ventilation and the transmission of airborne infection. There is strong and sufficient evidence to demonstrate the association between ventilation, air movements in buildings and the transmission/spread...

Potential of Natural Ventilation in Cold Conditions Countries

DEFF Research Database (Denmark)

Oropeza-Perez, Ivan; Østergaard, Poul Alberg

2014-01-01

The objective of this article is to investigate the energy performance of natural ventilation as a passive cooling method of buildings within houses located in temperate countries using Denmark as a case study. The method consists in running simulations with a thermal-airflow program of a household...... the simulations are validated with measured data, and by applying a new assessment method presented in this article as the cooling rate due to natural ventilation instead of a constant mechanical ventilation rate in the thermal balance within the dwelling, the energy saving is calculated. Results show...... ventilation rather mechanical one on large-scale scenarios located in temperate conditions. Finally, as a practical implication example, an assessment for Denmark is carried out....

24 CFR 570.205 - Eligible planning, urban environmental design and policy-planning-management-capacity building...

Science.gov (United States)

2010-04-01

... environmental design and policy-planning-management-capacity building activities. 570.205 Section 570.205..., urban environmental design and policy-planning-management-capacity building activities. (a) Planning... known or suspected environmental contamination. (5) [Reserved] (6) Policy—planning—management—capacity...

Natural Ventilation with Heat Recovery: A Biomimetic Concept

Directory of Open Access Journals (Sweden)

Zulfikar A. Adamu

2015-05-01

Full Text Available In temperate countries, heat recovery is often desirable through mechanical ventilation with heat recovery (MVHR. Drawbacks of MVHR include use of electric power and complex ducting, while alternative passive heat recovery systems in the form of roof or chimney-based solutions are limited to low rise buildings. This paper describes a biomimetic concept for natural ventilation with heat recovery (NVHR. The NVHR system mimics the process of water/mineral extraction from urine in the Loop of Henle (part of human kidney. Simulations on a facade-integrated Chamber successfully imitated the geometry and behaviour of the Loop of Henle (LoH. Using a space measuring 12 m2 in area and assuming two heat densities of 18.75 W/m2 (single occupancy or 30 W/m2 (double occupancy, the maximum indoor temperatures achievable are up to 19.3 °C and 22.3 °C respectively. These come with mean relative ventilation rates of 0.92 air changes per hour (ACH or 10.7 L·s−1 and 0.92 ACH (11.55 L·s−1, respectively, for the month of January. With active heating and single occupant, the LoH Chamber consumes between 65.7% and 72.1% of the annual heating energy required by a similar naturally ventilated space without heat recovery. The LoH Chamber could operate as stand-alone indoor cabinet, benefitting refurbishment of buildings and evading constraints of complicated ducting, external aesthetic or building age.

Evaluation of Heating, Ventilation, and Air conditioning (HVAC System Performance in an Administrative Building in Tehran (Iran

Directory of Open Access Journals (Sweden)

H. Mari Oriyad

2014-09-01

Full Text Available Introduction: One of the factors influencing on indoor air quality of the buildings is performance of HVAC (heating, ventilation, and air conditioning systems. These systems supply clean and odorless air, with temperature, humidity, and air velocity within comfort ranges for the residents. The aim of this study was to evaluate performance HVAC system in an administrative building in Tehran. .Material and Method: A questionnaire, developed in their research was used to assess the building occupants’ perception about the performance of HVAC system. To evaluate the performance of HVAC systems, air velocities were measured in the diffusers using a thermal anemometer. Moreover, CO2 concentration, air temperature and relative humidity were measured in the whole floors of the building. Air distribution inside the building was evaluated using smoke test. .Results: Most of the studied people complained about the direction of airflow, thermal conditions and cigarette odor. The highest level of carbon dioxide was measured at 930 ppm inside the restaurant. The maximum and minimum air temperatures and relative humidity were measured 28.3-13.8° C and 28.4-23% respectively. Smoke test showed that the air distribution/direction wasn’t suitable in one third of air diffusers. .Conclusion: Improper air distribution / direction was the main problem with the studied HVAC system which could be corrected by adjusting and balancing of the system.

8th International Symposium on Heating, Ventilation and Air Conditioning

CERN Document Server

Zhu, Yingxin; Li, Yuguo; Vol.1 Indoor and Outdoor Environment; Vol.2 HVAC&R Component and Energy System; Vol.3 Building Simulation and Information Management

2014-01-01

Proceedings of the 8th International Symposium on Heating, Ventilation and Air Conditioning is based on the 8th International Symposium of the same name (ISHVAC2013), which took place in Xi’an on October 19-21, 2013. The conference series was initiated at Tsinghua University in 1991 and has since become the premier international HVAC conference initiated in China, playing a significant part in the development of HVAC and indoor environmental research and industry around the world. This international conference provided an exclusive opportunity for policy-makers, designers, researchers, engineers and managers to share their experience. Considering the recent attention on building energy consumption and indoor environments, ISHVAC2013 provided a global platform for discussing recent research on and developments in different aspects of HVAC systems and components, with a focus on building energy consumption, energy efficiency and indoor environments. These categories span a broad range of topics, and the proce...

24 CFR 1003.205 - Eligible planning, urban environmental design and policy-planning-management-capacity building...

Science.gov (United States)

2010-04-01

... environmental design and policy-planning-management-capacity building activities. 1003.205 Section 1003.205... planning, urban environmental design and policy-planning-management-capacity building activities. (a... plans, general environmental studies, and strategies and action programs to implement plans, including...

Basement depressurization using dwelling mechanical exhaust ventilation system

International Nuclear Information System (INIS)

Collignan, B.; O'Kelly, P.; Pilch, E.

2004-01-01

The mechanical ventilation exhaust system is commonly used in France to generate air renewal into building and especially into dwelling. It consists of a permanent mechanical air extraction from technical rooms (kitchen, bathrooms and toilets) using a unique fan connected to exhaust ducts. Natural air inlets in living room and bed rooms ensure an air flow from living spaces towards technical rooms. To fight against radon into building, the most recognised efficient technique is the Soil Depressurization System (S.D.S.) consisting in depressurizing the house basement. The aim of this study is to test the ability of the dwelling mechanical ventilation system to depressurize the basement in conjunction with air renewal of a house. For that purpose, a S.D.S. has been installed in an experimental house at CSTB during its construction. At first, tests undertaken with a variable velocity fan connected to the S.D.S. have characterised the permeability of the basement. It is shown that basement can be depressurized adequately with a relatively low air flow rate. At a second stage, S.D.S. has been connected to the exhaust ventilation fan used for the mechanical ventilation of the house. Results obtained show the ability of such ventilation system to generate sufficient depressurization in the basement and to ensure simultaneously adequate air change rate in the dwelling. (author)

Method to assess the performance of domestic ventilation systems considering the influence of uncertainties

NARCIS (Netherlands)

Yang, Z.

2012-01-01

The ventilation system plays an important role in the indoor environment of a domestic building. A ventilation system is normally designed based on the national or regional regulations. Although ventilation systems are designed based on the same design rules, performance deviations between different

Comparative study of commercial building energy-efficiency retrofit policies in four pilot cities in China

International Nuclear Information System (INIS)

Hou, Jing; Liu, Yisheng; Wu, Yong; Zhou, Nan; Feng, Wei

2016-01-01

The energy efficiency of existing commercial buildings is more challenging to regulate and improve than the energy efficiency of new constructions. In 2011 and 2012, the Chinese Government selected four cities- Shanghai, Tianjin, Shenzhen, and Chongqing- to implement pilot commercial building energy efficiency retrofit program. Based on site surveys and expert interviews in these pilot cities, this research conducted a comparative analysis on incentive policies of local city level. The analysis results show that policy designs of existing commercial buildings should be further improved. The aspects that influence the implementation effect in the future, such as subsidy level, installments, and business model promotion, should be specified in the policy clauses. Referring to the technical solution and cost-benefit in Chongqing, we found that lighting system is the most common retrofit objects while envelope system is the least common one. And the subsidy incentive is greatest for educational buildings, followed by office buildings. In the end, we further discussed the problems and obstacles in commercial building retrofit market, and provided a series of recommendations. - Highlights: • Data and information were collected through site surveys to the four pilot cities. • Policy design and effectiveness in four cities were comparatively analyzed. • Well-designed policy increases market response, energy savings and EMC adoption. • Lighting is the most common retrofit while envelope is the least common one. • Subsidy incentive is greatest for educational buildings due to the utility tariff.

Building policy leadership among HIV/AIDS health workers | IDRC ...

International Development Research Centre (IDRC) Digital Library (Canada)

2016-04-21

Apr 21, 2016 ... Health workers need research, leadership, and policy skills to help ... the regions hardest hit by the pandemic, by building these skills among ... Nowhere in the world has AIDS had a more devastating effect than in Africa.

Health and economic benefits of building ventilation interventions for reducing indoor PM2.5 exposure from both indoor and outdoor origins in urban Beijing, China.

Science.gov (United States)

Yuan, Ye; Luo, Zhiwen; Liu, Jing; Wang, Yaowu; Lin, Yaoyu

2018-06-01

China is confronted with serious PM 2.5 pollution, especially in the capital city of Beijing. Exposure to PM 2.5 could lead to various negative health impacts including premature mortality. As people spend most of their time indoors, the indoor exposure to PM 2.5 from both indoor and outdoor origins constitutes the majority of personal exposure to PM 2.5 pollution. Different building interventions have been introduced to mitigate indoor PM 2.5 exposure, but always at the cost of energy expenditure. In this study, the health and economic benefits of different ventilation intervention strategies for reducing indoor PM 2.5 exposure are modeled using a representative urban residence in Beijing, with consideration of different indoor PM 2.5 emission strengths and outdoor pollution. Our modeling results show that the increase of envelope air-tightness can achieve significant economic benefits when indoor PM 2.5 emissions are absent; however, if an indoor PM 2.5 source is present, the benefits only increase slightly in mechanically ventilated buildings, but may show negative benefit without mechanical ventilation. Installing mechanical ventilation in Beijing can achieve annual economic benefits ranging from 200yuan/capita to 800yuan/capita if indoor PM 2.5 sources exist. If there is no indoor emission, the annual benefits above 200yuan/capita can be achieved only when the PM 2.5 filtration efficiency is no urban Beijing will increase the indoor PM 2.5 exposure and result in excess costs to the residents. Copyright © 2018 Elsevier B.V. All rights reserved.

Performance of displacement ventilation in practice

DEFF Research Database (Denmark)

Naidenov, K.; Pitchurov, G.; Langkilde, Gunnar

2002-01-01

This paper presents results of a field study in offices with displacement ventilation. It comprises detailed physical measurements of the thermal environment and collection of occupants´ response at 227 workplaces. The results, both physical measurements and human response, identified draught...... as the major local discomfort in the rooms with displacement ventilation. Twenty-three percent of the occupants were daily bothered by draught. In some buildings the maintenance personnel tried to improve occupants´ thermal comfort by raising the supply air temperature or office workers themselves blocked...

Mechanical ventilation with heat recovery in cold climates

DEFF Research Database (Denmark)

Kragh, Jesper; Rose, Jørgen; Svendsen, Svend

2005-01-01

Building ventilation is necessary to achieve a healthy and comfortable indoor environment, but as energy prices continue to rise it is necessary to reduce the energy consumption. Using mechanical ventilation with heat recovery reduces the ventilation heat loss significantly, but in cold climates...... freezes to ice. The analysis of measurements from existing ventilation systems with heat recovery used in single-family houses in Denmark and a test of a standard heat recovery unit in the laboratory have clearly shown that this problem occurs when the outdoor temperature gets below approximately –5º......C. Due to the ice problem mechanical ventilation systems with heat recovery are often installed with an extra preheating system reducing the energy saving potential significantly. New designs of high efficient heat recovery units capable of continuously defrosting the ice without using extra energy...

On the influence of the ventilation rate to the radiation burden in dwellings

International Nuclear Information System (INIS)

Tschurlovits, M.

1980-01-01

Calculations on the influence of the ventilation rate to the concentration of radon in dwellings from radioactive material of natural origin in building material are completed with a few examples of measurements. In addition, the optimization of the ventilation rate and the consequences of poorly ventilated dwellings are reported briefly. (author)

An innovation wall model based on interlayer ventilation

International Nuclear Information System (INIS)

Feng Jinmei; Lian Zhiwei; Hou Zhijian

2008-01-01

The thermal characteristics of the external wall are important to the energy consumption of the air conditioning system. Great attention should also be paid to the energy loss of the air exhaust. An innovation wall model based on interlayer ventilation is presented in this paper. The interlayer ventilation wall combines the wall and air exhaust of heating, ventilating and air conditioning (HVAC). The results of the experiment show that the energy loss of the exhaust air can be fully recovered by the interlayer ventilation wall. The cooling load can be reduced greatly because the temperature difference between the internal surface of the interlayer ventilation wall and the indoor air is very small. Clearly, the small temperature difference can enhance thermal comfort. In order to popularize the interlayer ventilation wall, technical and economical analysis is presented in this paper. Based on the buildings in the Shanghai area and a standard air conditioning system, a 4 years payback period for interlayer ventilation wall implementation was found according to the analysis

Building Assessment Survey and Evaluation Study Summarized Data - HVAC Characteristics

Science.gov (United States)

In the Building Assessment Survey and Evaluation (BASE) Study Information on the characteristics of the heating, ventilation, and air conditioning (HVAC) system(s) in the entire BASE building including types of ventilation, equipment configurations, and operation and maintenance issues was acquired by examining the building plans, conducting a building walk-through, and speaking with the building owner, manager, and/or operator.

Hybrid ventilation - functional technology or an ism in architecture?; Hybrid ventilation - funksjonell teknologi eller en isme i arkitekturen?

Energy Technology Data Exchange (ETDEWEB)

Amdahl, Leif

2003-07-01

Hybrid ventilation is launched in bold full-scale tests at many places in Norway. The article asks if this is nostalgia, like a kind of back-to-nature thinking, or does it mean innovation and sustainability? So far the insight into this type of ventilation is rather modest, and only few of the actors in the sector can be said to master the theory behind it. The author has visited a recently completed building in Levanger and describes his impression. There are three equal ventilation systems in the building, each having its own intake tower and culvert system for air supply to the individual rooms. In spite of the low intake velocity, under special weather circumstances, snow drifts all the way on to the filters. The air supply to the various rooms takes place diffusely as displacement ventilation, but the positions of the inlet valves on the external walls are dangerously close to the working places, which may cause trouble for different furnishing. The supply- and exhaust fans are pressure controlled, which works well. Heat recovery is based on water/glycol and dimensioned for 50 per cent efficiency. As a preliminary conclusion, the author considers the system as one of more ways of achieving a good indoor environment without complaints. But he does not understand why this type of ducts yields cleaner and better air than ordinary steel sheet ducts.

Green Building Policy Options for New Orleans

Energy Technology Data Exchange (ETDEWEB)

Doris, E.

2011-09-01

This document is adapted from a memo and report delivered to the City Council of New Orleans, the office of the Mayor of New Orleans, the Chairperson of the Citizen Stakeholders Group (New Orleans Energy Task Force) and the U.S. Department of Energy (DOE) Project Officer in 2008. The report outlines ideas for and potential impacts of various green building policies in New Orleans in the years following Hurricane Katrina.

Evaluation of an Incremental Ventilation Energy Model for Estimating Impacts of Air Sealing and Mechanical Ventilation

Energy Technology Data Exchange (ETDEWEB)

Logue, Jennifer M. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Turner, Willliam JN [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Walker, Iain S. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Singer, Brett C. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2012-07-01

Changing the rate of airflow through a home affects the annual thermal conditioning energy. Large-scale changes to airflow rates of the housing stock can significantly alter the energy consumption of the residential energy sector. However, the complexity of existing residential energy models hampers the ability to estimate the impact of policy changes on a state or nationwide level. The Incremental Ventilation Energy (IVE) model developed in this study was designed to combine the output of simple airflow models and a limited set of home characteristics to estimate the associated change in energy demand of homes. The IVE model was designed specifically to enable modelers to use existing databases of home characteristics to determine the impact of policy on ventilation at a population scale. In this report, we describe the IVE model and demonstrate that its estimates of energy change are comparable to the estimates of a wellvalidated, complex residential energy model when applied to homes with limited parameterization. Homes with extensive parameterization would be more accurately characterized by complex residential energy models. The demonstration included a range of home types, climates, and ventilation systems that cover a large fraction of the residential housing sector.

Development of a Residential Integrated Ventilation Controller

Energy Technology Data Exchange (ETDEWEB)

Staff Scientist; Walker, Iain; Sherman, Max; Dickerhoff, Darryl

2011-12-01

The goal of this study was to develop a Residential Integrated Ventilation Controller (RIVEC) to reduce the energy impact of required mechanical ventilation by 20percent, maintain or improve indoor air quality and provide demand response benefits. This represents potential energy savings of about 140 GWh of electricity and 83 million therms of natural gas as well as proportional peak savings in California. The RIVEC controller is intended to meet the 2008 Title 24 requirements for residential ventilation as well as taking into account the issues of outdoor conditions, other ventilation devices (including economizers), peak demand concerns and occupant preferences. The controller is designed to manage all the residential ventilation systems that are currently available. A key innovation in this controller is the ability to implement the concept of efficacy and intermittent ventilation which allows time shifting of ventilation. Using this approach ventilation can be shifted away from times of high cost or high outdoor pollution towards times when it is cheaper and more effective. Simulations, based on the ones used to develop the new residential ventilation requirements for the California Buildings Energy code, were used to further define the specific criteria and strategies needed for the controller. These simulations provide estimates of the energy, peak power and contaminant improvement possible for different California climates for the various ventilation systems. Results from a field test of the prototype controller corroborate the predicted performance.

Subjective evaluation of different ventilation concepts combined with radiant heating and cooling

DEFF Research Database (Denmark)

Krajcik, Michal; Tomasi, Roberta; Simone, Angela

2012-01-01

Sixteen subjects evaluated the indoor environment in four experiments with different combinations of ventilation and radiant heating/cooling systems. Two test setups simulated a room in a low energy building with a single occupant during winter. The room was equipped either by a ventilation system...... supplying warm air space heating or by a combination of radiant floor heating and mixing ventilation system. Next two test setups simulated an office room with two occupants during summer, ventilated and cooled by a single displacement ventilation system or by a radiant floor cooling combined...

The Dutch sustainable building policy: A model for developing countries?

Energy Technology Data Exchange (ETDEWEB)

Melchert, Luciana [Faculty of Architecture and Urbanism, University of Sao Paulo, Rua do Lago, 876, CEP 05508.900, Sao Paulo SP (Brazil)

2007-02-15

This article explores the institutionalization of environmental policies in the Dutch building sector and the applicability of the current model to developing countries. First, it analyzes the transition of sustainable building practices in the Netherlands from the 1970s until today, exploring how these were originally embedded in a discourse on 'de-modernization', which attempted to improve the environmental performance of building stocks by means of self-sufficient technologies, whereas nowadays they adopt a framework of 'ecological modernization', with integrative approaches seeking to improve the environmental performance of building stocks through more efficient-rather than self-sufficient-technologies. The study subsequently shows how the current Dutch sustainable building framework has thereby managed to achieve a pragmatic and widely accepted rationale, which can serve to orient the ecological restructuring of building stocks in developing countries. (author)

Hybrid Ventilation with Innovative Heat Recovery—A System Analysis

Directory of Open Access Journals (Sweden)

Bengt Hellström

2013-02-01

Full Text Available One of the most important factors when low energy houses are built is to have good heat recovery on the ventilation system. However, standard ventilation units use a considerable amount of electricity. This article discusses the consequences on a system level of using hybrid ventilation with heat recovery. The simulation program TRNSYS was used in order to investigate a ventilation system with heat recovery. The system also includes a ground source storage and waste water heat recovery system. The result of the analysis shows that the annual energy gain from ground source storage is limited. However, this is partly a consequence of the fact that the well functioning hybrid ventilation system leaves little room for improvements. The analysis shows that the hybrid ventilation system has potential to be an attractive solution for low energy buildings with a very low need for electrical energy.

Building sustainable policy framework for transport development: A review of national transport policy initiatives in Nigeria

Directory of Open Access Journals (Sweden)

Sumaila A.F.

2013-06-01

Full Text Available This paper is concerned with building a sustainable policy framework for transport development in Nigeria. Its objective is to review the country’s transport policy initiatives in order to understand the extent to which it addresses Nigeria’s mobility and transportation problems. From published materials and official government documents and files, the study identifies four national policy initiatives which are reviewed and analysed with regard to their context, contents, and consequences. The study reveals that while the policy initiatives could be said to be adequate and comprehensive in terms of their context and contents, the major challenge is implementation of recommended solutions. The study therefore provides a general checklist to guide policy direction, while advocating for policy-based researches and empirical studies in order to provide the data base for formulation of a sustainable national transport policy for Nigeria.

The effect of ventilation on the indoor air concentration of PCB

DEFF Research Database (Denmark)

Lyng, Nadja; Gunnarsen, Lars Bo; Andersen, Helle Vibeke

2015-01-01

The impact of increased ventilation on polychlorinated biphenyl (PCB) air concentration by installation of mechanical balanced ventilation units was studied. The intervention was carried out in three PCB-contaminated rooms; one classroom in an elementary school and two small bedrooms...... in an apartment in a residential building. In the classroom, the air exchange rate (ACH) was raised from 0.2 (without mechanical ventilation) to 5.5 /h during the intervention. In the two bedrooms, the highest ACH was 6.6 /h and 0.5 /h without mechanical ventilation. The corresponding concentration decrease...

Balancing energy conservation and occupant needs in ventilation rate standards for Big Box stores and other commercial buildings in California. Issues related to the ASHRAE 62.1 Indoor Air Quality Procedure

Energy Technology Data Exchange (ETDEWEB)

Mendell, Mark J. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Apte, Mike G. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

2010-10-31

This report considers the question of whether the California Energy Commission should incorporate the ASHRAE 62.1 ventilation standard into the Title 24 ventilation rate (VR) standards, thus allowing buildings to follow the Indoor Air Quality Procedure. This, in contrast to the current prescriptive standard, allows the option of using ventilation rate as one of several strategies, which might include source reduction and air cleaning, to meet specified targets of indoor air concentrations and occupant acceptability. The research findings reviewed in this report suggest that a revised approach to a ventilation standard for commercial buildings is necessary, because the current prescriptive ASHRAE 62.1 Ventilation Rate Procedure (VRP) apparently does not provide occupants with either sufficiently acceptable or sufficiently healthprotective air quality. One possible solution would be a dramatic increase in the minimum ventilation rates (VRs) prescribed by a VRP. This solution, however, is not feasible for at least three reasons: the current need to reduce energy use rather than increase it further, the problem of polluted outdoor air in many cities, and the apparent limited ability of increasing VRs to reduce all indoor airborne contaminants of concern (per Hodgson (2003)). Any feasible solution is thus likely to include methods of pollutant reduction other than increased outdoor air ventilation; e.g., source reduction or air cleaning. The alternative 62.1 Indoor Air Quality Procedure (IAQP) offers multiple possible benefits in this direction over the VRP, but seems too limited by insufficient specifications and inadequate available data to provide adequate protection for occupants. Ventilation system designers rarely choose to use it, finding it too arbitrary and requiring use of much non-engineering judgment and information that is not readily available. This report suggests strategies to revise the current ASHRAE IAQP to reduce its current limitations. These

Optimisation topologique d'une bouche de ventilation en régime turbulent

OpenAIRE

Riviere , Garry; Cocquet , Pierre-Henri; Fock , Eric; Bastide , Alain

2016-01-01

National audience; The air velocity is one of the thermal comfort criteria for building users. Thus, an increase of air velocity on building users contributes to reduce perceived temperature. Therefore, air movement in the areas of users improves thermal comfort. Airflow dynamics may be changed by altering the design aspect of the ventilation nozzles. To achieve suitable air velocity, the design methods of ventilation nozzles are based on experimental tests or numerical trial and error method...

Electricity utilization for ventilation purposes in new and old offices; Elanvaendning foer ventilation i nya och gamla kontor

Energy Technology Data Exchange (ETDEWEB)

Westerberg, J. [Stockholm Univ. (Sweden)

1995-12-31

The consumption of electric power for ventilation purposes in new office buildings is compared with an investigation made 1990-91. This study will be used in two planning scenarios, `frozen efficiency` and BaU (Business as Usual). With the technology of 1980s the power used for ventilation will increase from 190 GWh in 1991 to 210 GWh in the year 2010. The technology of the 1990s will give an increase to 205 GWh in the year 2010. 21 refs, 21 figs, 2 tabs

Electricity utilization for ventilation purposes in new and old offices; Elanvaendning foer ventilation i nya och gamla kontor

Energy Technology Data Exchange (ETDEWEB)

Westerberg, J [Stockholm Univ. (Sweden)

1996-12-31

The consumption of electric power for ventilation purposes in new office buildings is compared with an investigation made 1990-91. This study will be used in two planning scenarios, `frozen efficiency` and BaU (Business as Usual). With the technology of 1980s the power used for ventilation will increase from 190 GWh in 1991 to 210 GWh in the year 2010. The technology of the 1990s will give an increase to 205 GWh in the year 2010. 21 refs, 21 figs, 2 tabs

Analysis of energy efficiency retrofit schemes for heating, ventilating and air-conditioning systems in existing office buildings based on the modified bin method

International Nuclear Information System (INIS)

Wang, Zhaoxia; Ding, Yan; Geng, Geng; Zhu, Neng

2014-01-01

Highlights: • A modified bin method is adopted to propose and optimize the EER schemes. • A case study is presented to demonstrate the analysis procedures of EER schemes. • Pertinent EER schemes for HVAC systems are proposed for the object building. - Abstract: Poor thermal performance of building envelop and low efficiencies of heating, ventilating and air-conditioning (HVAC) systems can always be found in the existing office buildings with large energy consumption. This paper adopted a modified bin method to propose and optimize the energy efficiency retrofit (EER) schemes. An existing office building in Tianjin was selected as an example to demonstrate the procedures of formulating the design scheme. Pertinent retrofit schemes for HVAC system were proposed after the retrofit of building envelop. With comprehensive consideration of energy efficiency and economic benefits, the recommended scheme that could improve the overall energy efficiency by 71.20% was determined

Experimental and numerical analysis of mixing ventilation at laminar, transitional and turbulent slot Reynolds numbers

NARCIS (Netherlands)

Hooff, van T.A.J.

2012-01-01

The proper ventilation of buildings and other enclosures such as airplanes, trains, ships and cars is of primary interest in engineering with respect to human (thermal) comfort, energy efficiency and sustainability. One of the most commonly applied ventilation methods is mixing ventilation, which is

Energy - efficient buildings in pakistan

International Nuclear Information System (INIS)

Sohail, M.; Qureshi, M.U.D.

2011-01-01

Pakistan is one of the countries with the highest energy consumption for domestic use. Annual energy consumption by the domestic sector is 45.9 % of the total, while the industrial sector, consumes about 27.5%. About half of the total energy consumed is used in buildings and/or heating, ventilation and air-conditioning (HVAC) and lighting appliances. The energy consumed for the same purposes in China and UK is 25 to 30 % and 40 %, respectively, even in extreme weather conditions. Energy deficiency in Pakistan is approximately 5,000 MWe, which results in worst load-shedding in summers and, lately, even in winters. Building new energy sources like dams, coal power plants and renewable energy power projects are some possible solutions, but these are time taking and need at least 2 to 6 years to complete, depending upon the nature of the project. Fast development of energy-efficient buildings is, therefore, necessary to deal with exacerbating energy-crisis and related environmental impact in Pakistan. Innovations in the prevailing building-design will help the country in reducing the energy burden. These innovations may include improved architectural designs, energy-efficient building materials, electrical appliances and implementation of building energy-efficiency codes. In 1987, the National Energy Conservation Centre (ENERCON), was established under Ministry of Environment, Government of Pakistan, with the aim to build awareness among the masses for energy conservation, and to make policies regarding energy-conservation structures in the country. But no policy regarding building energy codes has been introduced by ENERCON till now. In collaboration with Pakistan Engineering Council (PEC), ENERCON has recently finalized the Building Energy Code of Pakistan Energy Provisions 2011 for which statutory notification is under process for necessary amendment in the building by-laws. The implementation of this Energy Code will result in 25 to 30 % of energy savings in the

The use of computational method to assess the safety and quality of ventilation in industrial buildings

International Nuclear Information System (INIS)

Broyd, T.W.; Oldfield, S.G.; Moult, A.

1983-01-01

Industrial buildings, particularly those containing nuclear and process plant, often require high standards of ventilation in order to cope with unusual features of the operations or process which take place within the buildings. Four examples of recent studies carried out by the present authors are given in this paper: storage of coal in a covered stockyard, a chlor-alkali plant, a clean room, and the turbine hall of a nuclear power station. In each of these examples, quite detailed information was required about air flows, temperatures and gas concentrations, and it was decided to use the two-equation k,epsilon model of turbulence to help predict these variables. This is solved with equations for momentum and continuity by finite differences. It is concluded that complex computer programs of this kind can provide valuable assistance in support of the more traditional hand calculations using BS codes and CIBS guides. However, careful engineering judgement must be exercised in the use of the programs and in the interpretation of the results. (author)

Validity of thermally-driven small-scale ventilated filling box models

Science.gov (United States)

Partridge, Jamie L.; Linden, P. F.

2013-11-01

The majority of previous work studying building ventilation flows at laboratory scale have used saline plumes in water. The production of buoyancy forces using salinity variations in water allows dynamic similarity between the small-scale models and the full-scale flows. However, in some situations, such as including the effects of non-adiabatic boundaries, the use of a thermal plume is desirable. The efficacy of using temperature differences to produce buoyancy-driven flows representing natural ventilation of a building in a small-scale model is examined here, with comparison between previous theoretical and new, heat-based, experiments.

Improvenet of The Broiler House Ventilation Using The CFD Simulation

Czech Academy of Sciences Publication Activity Database

Zajíček, Milan; Kic, P.

Volume 10, Spec. 1 (2012), s. 235-242 ISSN 1406-894X. [Biosystems Engineering 2012. Tartu, 10.05.2012-11.05.2012] Institutional support: RVO:67985556 Keywords : broiler house * ventilation * fluid dynamics Subject RIV: GB - Machines ; Buildings for Agriculture http://library.utia.cas.cz/separaty/2012/VS/zajicek-improvenet of the broiler house ventilation using the cfd simulation.pdf

: ventilators for noninvasive ventilation

OpenAIRE

Fauroux , Brigitte; Leroux , Karl; Desmarais , Gilbert; Isabey , Daniel; Clément , Annick; Lofaso , Frédéric; Louis , Bruno

2008-01-01

International audience; The aim of the present study was to evaluate the performance characteristics of all the ventilators proposed for home noninvasive positive-pressure ventilation in children in France. The ventilators (one volume-targeted, 12 pressure-targeted and four dual) were evaluated on a bench which simulated six different paediatric ventilatory patterns. For each ventilator, the quality of the inspiratory and expiratory trigger and the ability to reach and maintain the preset pre...

Optimization of Occupancy Based Demand Controlled Ventilation in Residences

DEFF Research Database (Denmark)

Mortensen, Dorthe Kragsig; Walker, Iain; Sherman, Max

2011-01-01

Although it has been used for many years in commercial buildings, the application of demand controlled ventilation in residences is limited. In this study we used occupant exposure to pollutants integrated over time (referred to as "dose") as the metric to evaluate the effectiveness and air quality...... implications of demand controlled ventilation in residences. We looked at air quality for two situations. The first is that typically used in ventilation standards: the exposure over a long term. The second is to look at peak exposures that are associated with time variations in ventilation rates and pollutant...... when occupied. We used analytical solutions to the continuity equation to determine the ventilation effectiveness and the long-term chronic dose and peak acute exposure for a representative range of occupancy periods, pollutant generation rates and airflow rates. The results of the study showed that we...

Building policy-making capacity in the Ministry of Health: the Kazakhstan experience.

Science.gov (United States)

Chanturidze, Tata; Adams, Orvill; Tokezhanov, Bolat; Naylor, Mike; Richardson, Erica

2015-01-20

Recent economic growth in Kazakhstan has been accompanied by slower improvements in population health and this has renewed impetus for health system reform. Strengthening strategic planning and policy-making capacity in the Ministry of Health has been identified as an important priority, particularly as the Ministry of Health is leading the health system reform process. The intervention was informed by the United Nations Development Programme (UNDP) framework for capacity building which views capacity building as an ongoing process embedded in local institutions and practices. In response to local needs extra elements were included in the framework to tailor the capacity building programme according to the existing policy and budget cycles and respective competence requirements, and link it with transparent career development structures of the Ministry of Health. This aspect of the programme was informed by the institutional capability assessment model used by the United Kingdom National Health Service (NHS) which was adapted to examine the specific organizational and individual competences of the Ministry of Health in Kazakhstan. There were clear successes in building capacity for policy making and strategic planning within the Ministry of Health in Kazakhstan, including better planned, more timely and in-depth responses to policy assignments. Embedding career development as a part of this process was more challenging. This case study highlights the importance of strong political will and high level support for capacity building in ensuring the sustainability of programmes. It also shows that capacity-building programmes need to ensure full engagement with all local stakeholders, or where this is not possible, programmes need to be targeted narrowly to those stakeholders who will benefit most, for the greatest impact to be achieved. In sum, high quality tailor-made capacity development programmes should be based on thorough needs assessment of individual and

Measure Guideline: Selecting Ventilation Systems for Existing Homes

Energy Technology Data Exchange (ETDEWEB)

Aldrich, Robb [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2014-02-01

This document addresses adding -or improving - mechanical ventilation systems to existing homes. The purpose of ventilation is to remove contaminants from homes, and this report discusses where, when, and how much ventilation is appropriate in a home, including some discussion of relevant codes and standards. Advantages, disadvantages, and approximate costs of various system types are presented along with general guidelines for implementing the systems in homes. CARB intends for this document to be useful to decision makers and contractors implementing ventilation systems in homes. Choosing the "best" system is not always straightforward; selecting a system involves balancing performance, efficiency, cost, required maintenance, and several other factors. It is the intent of this document to assist contractors in making more informed decisions when selecting systems. Ventilation is an integral part of a high-performance home. With more air-sealed envelopes, a mechanical means of removing contaminants is critical for indoor environmental quality and building durability.

Acceptance of low-flow mechanical ventilation in dwellings

International Nuclear Information System (INIS)

Mueller, V.; Peters, M.; Gubler, M.; Maillard, S.; Keller, L.

2001-01-01

This report presents the findings of a survey carried out on the acceptance of 'low-flow mechanical ventilation' (a fan-assisted balanced ventilation with heat recovery) for houses and apartments in Switzerland. The results were obtained on the one hand by reviewing and analysing articles appearing on the subject in the professional and daily press and by telephone interviews with 100 randomly chosen architects and 100 investors in the German and French-speaking parts of Switzerland on the other. These survey participants were asked to express their views on low-flow mechanical ventilation and experience already gained in this area. Further Interviews with tenants, 150 of whom lived in buildings fitted with low-flow mechanical ventilation and 300 in dwellings without this form of ventilation, provided information on the attitude of those directly affected, their satisfaction with the systems or their wishes. The report analyses the results of the surveys and proposes a plan of action to improve information and training for architects, owners and tenants

Low air exchange rate causes high indoor radon concentration in energy-efficient buildings

International Nuclear Information System (INIS)

Vasilyev, A.V.; Yarmoshenko, I.V.; Zhukovsky, M.V.

2015-01-01

Since 1995, requirements on energy-efficient building construction were established in Russian Building Codes. In the course of time, utilisation of such technologies became prevailing, especially in multi-storey building construction. According to the results of radon survey in buildings constructed meeting new requirements on energy efficiency, radon concentration exceeds the average level in early-constructed buildings. Preponderance of the diffusion mechanism of radon entry in modern multi-storey buildings has been experimentally established. The experimental technique of the assessment of ventilation rate in dwellings under real conditions was developed. Based on estimates of average ventilation rate, it was approved that measures to increase energy efficiency lead to reduction in ventilation rate and accumulation of higher radon concentrations indoors. Obtained ventilation rate values have to be considered as extremely low. (authors)

21 CFR 211.46 - Ventilation, air filtration, air heating and cooling.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 4 2010-04-01 2010-04-01 false Ventilation, air filtration, air heating and cooling. 211.46 Section 211.46 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN... Buildings and Facilities § 211.46 Ventilation, air filtration, air heating and cooling. (a) Adequate...

Building envelope

CSIR Research Space (South Africa)

Gibberd, Jeremy T

2009-01-01

Full Text Available for use in the building. This is done through photovoltaic and solar water heating panels and wind turbines. Ideally these are integrated in the design of the building envelope to improve the aesthetic quality of the building and minimise material... are naturally ventilated. Renewable energy The building envelope includes renewable energy generation such as photovoltaics, wind turbines and solar water heaters and 10% of the building’s energy requirements are generated from these sources. Views All...

Energy and behavioral impacts of integrative retrofits for residential buildings: What is at stake for building energy policy reforms in northern China?

International Nuclear Information System (INIS)

Xu, Peng; Xu, Tengfang; Shen, Pengyuan

2013-01-01

Based upon the results from extensive building monitoring and surveys on occupant’s behaviors in a representative nine-story apartment building in northern China, building energy simulations were performed to evaluate the impacts of integrative retrofits implemented. Integrative retrofits required by the newer building energy standard produced significant heating-energy savings (i.e., 53%) when compared with baseline buildings commonly built in early 1980s. Taking into account district-heating-system upgrades as part of integrative retrofit measures, a representative apartment building was 66% more efficient than the baseline building. Contrary to expectation, little behavioral change was found in response to the provisions of monetary incentive, billing-method reform, or metering of heating energy use in individual apartment units. Yet this paper identified sizable energy savings potential if occupants’ behavioral changes were to actually happen. This indicates that provisions of financial incentives or individual metering were insufficient for triggering substantial behavioral changes leading toward more energy savings in the current buildings. It is recommended that innovative energy policies, technology upgrades, and education would be needed to promote behavioral changes toward additional energy savings. Finally, measures and strategies to further enhance thermal integrity criteria (e.g., insulations of roof and balcony) are recommended in China’s future building energy policy reforms. - Highlights: ► Integrative retrofits significantly reduce residential heating energy in north China. ► Energy effects of retrofits, incentive, billing and behavioral changes were studied. ► Monetary incentive, control or metering technologies did not lead to behavior change. ► Potential energy savings due to occupants’ behavioral changes are sizable. ► Thermal integrity needs to be enhanced in future building standards and policies.

Reducing Building HVAC Costs with Site-Recovery Energy

Science.gov (United States)

Pargeter, Stephen J.

2012-01-01

Building owners are caught between two powerful forces--the need to lower energy costs and the need to meet or exceed outdoor air ventilation regulations for occupant health and comfort. Large amounts of energy are wasted each day from commercial, institutional, and government building sites as heating, ventilation, and air conditioning (HVAC)…

Preoperational test report, recirculation ventilation systems

Energy Technology Data Exchange (ETDEWEB)

Clifton, F.T.

1997-11-11

This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System.

Preoperational test report, recirculation ventilation systems

International Nuclear Information System (INIS)

Clifton, F.T.

1997-01-01

This represents a preoperational test report for Recirculation Ventilation Systems, Project W-030. Project W-030 provides a ventilation upgrade for the four Aging Waste Facility tanks. The system provides vapor space cooling of tanks AY1O1, AY102, AZ1O1, AZ102 and supports the ability to exhaust air from each tank. Each system consists of a valved piping loop, a fan, condenser, and moisture separator; equipment is located inside each respective tank farm in its own hardened building. The tests verify correct system operation and correct indications displayed by the central Monitor and Control System

Feasibility of utilising solar-induced ventilation in Malaysia

International Nuclear Information System (INIS)

Ong, K.S.; Chow, C.C.

2006-01-01

The feasibility of applying solar-induced ventilation in a typical Malaysian house measuring 3 m high x wide x 5 m deep was considered based on experimental results obtained from a laboratory-scale model. A wall-type solar chimney was considered. The design of the solar chimney incorporated providing a glass panel alongside a vertical wall of a building. Openings at the top and bottom of the wall allowed fresh air to be introduced into the building. Simulations obtained from a simple theoretical model showed that the solar chimney was able to induce air flow rates of between 640 to 1040 m3 h-1 with a 0.3 m air gap. These ventilation rates are found to be in compliance with codes specified by ASHRAE and the Uniform Building By-laws. Full scale studies would need to be conducted in order to evaluate its effectiveness especially the flow pattern in the room

Perceived air quality and sensory pollution loads in six Danish office buildings

DEFF Research Database (Denmark)

Wargocki, Pawel; Krupicz, P.; Szczecinski, A.

2002-01-01

Perceived air quality and sensory pollution loads were measured in 6 office buildings with mechanical ventilation without recirculation, in each buildings in 6 representative non-smoking medium-sized and small offices with mixing ventilation. An untrained panel of 43 subjects assessed the air...... quality on a normal weekday when the building was occupied, and on a weekend without occupants in the building. On both occasions the ventilation system was in operation as on a normal working day. Outdoor air supply rate, air temperature, relative humidity, concentration of carbon dioxide and ultrafine...

Energy Saving Potential by Utilizing Natural Ventilation under Warm Conditions

DEFF Research Database (Denmark)

Oropeza-Perez, Ivan; Østergaard, Poul Alberg

2014-01-01

The objective of this article is to show the potential of natural ventilation as a passive cooling method within the residential sector of countries which are located in warm conditions using Mexico as a case study. The method is proposed as performing, with a simplified ventilation model, thermal......–airflow simulations of 27 common cases of dwellings (considered as one thermal zone) based on the combination of specific features of the building design, occupancy and climate conditions. The energy saving potential is assessed then by the use of a new assessment method suitable for large-scale scenarios using...... the actual number of air-conditioned dwellings distributed among the 27 cases. Thereby, the energy saving is presented as the difference in the cooling demand of the dwelling during one year without and with natural ventilation, respectively. Results indicate that for hot-dry conditions, buildings with high...

CFD model of air movement in ventilated facade: comparison between natural and forced air flow

Energy Technology Data Exchange (ETDEWEB)

Mora Perez, Miguel; Lopez Patino, Gonzalo; Lopez Jimenez, P. Amparo [Hydraulic and Environmental Engineering Department, Universitat Politècnica de Valencia (Spain)

2013-07-01

This study describes computational fluid dynamics (CFD) modeling of ventilated facade. Ventilated facades are normal facade but it has an extra channel between the concrete wall and the (double skin) facade. Several studies found in the literature are carried out with CFD simulations about the behavior of the thermodynamic phenomena of the double skin facades systems. These studies conclude that the presence of the air gap in the ventilated facade affects the temperature in the building skin, causing a cooling effect, at least in low-rise buildings. One of the most important factors affecting the thermal effects of ventilated facades is the wind velocity. In this contribution, a CFD analysis applied on two different velocity assumptions for air movement in the air gap of a ventilated facade is presented. A comparison is proposed considering natural wind induced velocity with forced fan induced velocity in the gap. Finally, comparing temperatures in the building skin, the differences between both solutions are described determining that, related to the considered boundary conditions, there is a maximum height in which the thermal effect of the induced flow is significantly observed.

Heating, ventilating, and air-conditioning applications

International Nuclear Information System (INIS)

Anon.

1991-01-01

This book covers: Comfort air conditioning and heating of residences: Space HVAC systems; Industrial and special air conditioning and ventilation for nuclear facilities, and for mines; Energy sources, such as Geothermal energy, solar utilization, and energy resources; Building operation and maintenance; energy management, and Thermal storage

Estimating wind frequency limits for natural ventilation at remote sites

International Nuclear Information System (INIS)

Su, B.; Aynsley, R.

2006-01-01

Detailed wind data are collected at a limited number of sites, usually at airports. When a building is sited remote from the nearest wind data collection site, estimating wind frequency is more complex. The techniques involved come from the discipline of wind engineering. Where there is a relatively flat terrain between the wind data-recording site and the building site, simple computations can be made to account for the wind velocities over intervening terrain roughness. Where significant topographic features such as hills or mountains are present between the wind data-recording site and the building site, then boundary layer wind tunnel studies will be necessary to determine the influence of such features on wind speed and direction. Rough estimates can be calculated using factors used in some wind loading codes. When buildings are to be designed to take advantage of the energy efficiency offered by natural ventilation, it is important to estimate the actual potential for such ventilation. The natural ventilation potential can be estimated in terms of the percentage of time when wind exceeds some minimum value. For buildings near airports this is a relatively simple procedure. Such estimates are important as they also indicate the likely percentage of time when fans or other energy consuming devices will be needed to maintain indoor thermal comfort. This paper identifies the wind engineering techniques that can be used for such estimates and gives examples of such calculations

Ventilation: Exploitation and maintenance. Ten years of experience

International Nuclear Information System (INIS)

Letertre, J.

1990-01-01

The evolution and the maintenance operations performed during the last ten years on the ventilation-air-conditioning system at the Hague plant are presented. The modifications operated in the ventilation-air-conditioning system were carried out in order to answer the safety requirements evolution due to the increase of the plant productivity. The choice and the results of the maintenance policies, defined as a function of the safety, quality and cost requirements, are presented [fr

XACML to build access control policies for Internet of Things

OpenAIRE

Atlam, Hany F.; Alassafi, Madini, Obad; Alenezi, Ahmed; Walters, Robert; Wills, Gary

2018-01-01

Although the Internet of things (IoT) brought unlimited benefits, it also brought many security issues. The access control is one of the main elements to address these issues. It provides the access to system resources only to authorized users and ensures that they behave in an authorized manner during their access sessions. One of the significant components of any access control model is access policies. They are used to build the criteria to permit or deny any access request. Building an ef...

Evaluating public policy instruments in the Greek building sector

International Nuclear Information System (INIS)

Spyridaki, Niki-Artemis; Banaka, Stefania; Flamos, Alexandros

2016-01-01

This paper applies a multi-criteria analysis (MCA) to evaluate public policy mechanisms that foster energy efficiency and renewable energy sources in the Greek building sector, based on stakeholders’ understanding and perceptions of the functionality of policy instruments. The objective is to shed light on the implementation of currently employed policy mechanisms that aim to achieve the 2020 energy savings targets and beyond, providing useful information to policy makers for future policy (re-) formulations. In this framework, policy instruments were evaluated against process-related criteria, such as implementation costs, distributional effects, and coherence of policy processes, so as to highlight successful policy practices during their implementation phase as well as to unveil cases of policy underperformance or unintended policy outcomes. To hedge uncertainties related to policy instrument selection, the method employs probabilistic evaluations of every alternative against each criterion. The MCA results showed that the country is still missing significant energy saving opportunities that could be reached through more streamlined implementation practices and political support. In times of fiscal crisis, the Greek government should also revitalize the implementation of alternative funding mechanisms and support policy alternatives such as green public procurement, voluntary agreements, and energy performance contracting. - Highlights: • We apply an MCA analysis to evaluate EE and RES policies instruments. • We focus on the implementation stage through qualitative criteria and ordinal scales. • We use the probabilistic evaluations of each alternative against each criterion. • We provide rankings of instruments according to process related criteria. • Greece should revitalize the implementation of funding mechanisms, GPP and VAs.

IMCOM LONWORKS Building Automation Systems Implementation Strategy

National Research Council Canada - National Science Library

Schwenk, David M; Bush, Joseph; Hughes, Lucie M; Briggs, Stephen; White, Will

2007-01-01

Army Installations often expand their use of digital control systems for heating, ventilating, and air conditioning and other mechanical and electrical building systems on a building-by-building basis...

Policy and Challenges of Building Schools as Inclusive Communities

Science.gov (United States)

Curcic, Svjetlana; Gabel, Susan L.; Zeitlin, Virginia; Cribaro-DiFatta, Shannon; Glarner, Carmel

2011-01-01

In this paper, we address building inclusive communities by looking at school as a community, as a place where students participate in learning and also learn to participate in the life of a community and life in a broader inclusive society. At the international level, policies increasingly position education as a business organisation, with…

A simulation Model of the Reactor Hall Ventilation and air Conditioning Systems of ETRR-2

International Nuclear Information System (INIS)

Abd El-Rahman, M.F.

2004-01-01

Although the conceptual design for any system differs from one designer to another. each of them aims to achieve the function of the system required. the ventilation and air conditioning system of reactors hall is one of those systems that really differs but always dose its function for which it is designed. thus, ventilation and air conditioning in some reactor hall constitute only one system whereas in some other ones, they are separate systems. the Egypt Research Reactor-2 (ETRR-2)represents the second type. most studies conducted on ventilation and air conditioning simulation models either in traditional building or for research rectors show that those models were not designed similarly to the model of the hall of ETRR-2 in which ventilation and air conditioning constitute two separate systems.besides, those studies experimented on ventilation and air conditioning simulation models of reactor building predict the temperature and humidity inside these buildings at certain outside condition and it is difficult to predict when the outside conditions are changed . also those studies do not discuss the influences of reactor power changes. therefore, the present work deals with a computational study backed by infield experimental measurements of the performance of the ventilation and air conditioning systems of reactor hall during normal operation at different outside conditions as well as at different levels of reactor power

Operational experience at RCD and FCD laboratories during various ventilation conditions

International Nuclear Information System (INIS)

Murali, S.; Ashok Kumar, P.; Thanamani, M.; Rath, D.P.; Sapkal, J.A.; Raman, Anand

2007-01-01

Radiochemistry and Fuel Chemistry wing of Radiological Laboratory facility has various radio-chemical operations on isotopes of plutonium and trans-plutonium elements, carried out under containment and safe operational conditions. The ventilation provided to the facility is a Once - through system. The ventilation system is designed with separate headers for laboratory and glove box exhausts. There is scheduled periodic shut down of ventilation system for maintenance during non-occupancy hours/week ends. The buildup of natural α - emitters activity due to ventilation shut down, observed to be prevailing on stack air sample filter papers after the ventilation startup, is studied. The paper describes the operational experience gained over a period during ventilation shut down and suggests the course of remedial action for reducing the internal exposure due to build up of natural α - emitters and their progenies. (author)

Stimulating energy-efficient innovations in the Dutch building sector: Empirical evidence from patent counts and policy lessons

International Nuclear Information System (INIS)

Noailly, Joelle; Batrakova, Svetlana

2010-01-01

In the Netherlands where the building sector accounts for 33% of carbon emissions, the government aims to halve the total energy use from buildings by 2030 compared to 1990 levels. To this end, the Dutch government has set specific goals in order to foster technological innovation related to energy efficiency in buildings. The objective of this paper is to explore the links between technological innovation and public policies in this sector over the last 30 years. The paper aims (1) to measure the evolution of innovations related to energy efficiency in buildings in the Netherlands using patent counts and (2) to provide a historical overview of the policy framework. Descriptive data on patenting activities show that the Netherlands have a clear comparative advantage in the field of energy-saving lighting technologies, mainly due to intensive patenting activities by Philips. High-efficiency boilers also represent a substantial share of Dutch innovation activities in this domain over the last decades. In many other fields (such as insulation, heat-pumps and cogeneration, solar boilers, etc.), however, Germany, Austria and Scandinavian countries rank much higher than the Netherlands. The descriptive analysis of Dutch energy policy shows an intensification of energy policy in the mid-1990s, followed by a slight decline after 2001. Overall, the simultaneous introduction of policy instruments makes it difficult to evaluate the effectiveness of policies. Also, the policy framework is characterized by the introduction of a large number of short-lived policy instruments and frequent policy changes. The lack of stability and continuity of energy policy may be damaging for innovation. - Research Highlights: →The Netherlands are a top innovative country in the field of energy-efficient innovations for buildings, mainly due to high patenting activities by Philips in energy-saving lighting technologies. →In many other fields (insulation, heat-pumps, etc) Germany, Austria and

Argonne Fuel Cycle Facility ventilation system -- modeling and results

International Nuclear Information System (INIS)

Mohr, D.; Feldman, E.E.; Danielson, W.F.

1995-01-01

This paper describes an integrated study of the Argonne-West Fuel Cycle Facility (FCF) interconnected ventilation systems during various operations. Analyses and test results include first a nominal condition reflecting balanced pressures and flows followed by several infrequent and off-normal scenarios. This effort is the first study of the FCF ventilation systems as an integrated network wherein the hydraulic effects of all major air systems have been analyzed and tested. The FCF building consists of many interconnected regions in which nuclear fuel is handled, transported and reprocessed. The ventilation systems comprise a large number of ducts, fans, dampers, and filters which together must provide clean, properly conditioned air to the worker occupied spaces of the facility while preventing the spread of airborne radioactive materials to clean am-as or the atmosphere. This objective is achieved by keeping the FCF building at a partial vacuum in which the contaminated areas are kept at lower pressures than the other worker occupied spaces. The ventilation systems of FCF and the EBR-II reactor are analyzed as an integrated totality, as demonstrated. We then developed the network model shown in Fig. 2 for the TORAC code. The scope of this study was to assess the measured results from the acceptance/flow balancing testing and to predict the effects of power failures, hatch and door openings, single-failure faulted conditions, EBR-II isolation, and other infrequent operations. The studies show that the FCF ventilation systems am very controllable and remain stable following off-normal events. In addition, the FCF ventilation system complex is essentially immune to reverse flows and spread of contamination to clean areas during normal and off-normal operation

Ensuring the long service life of unheated buildings. Evaluation methods to avoid moisture damage in unheated buildings

Energy Technology Data Exchange (ETDEWEB)

Viljanen, M.; Bergman, J.; Grabko, S.; Lu Xiaoshu; Yrjoelae, R.

1999-07-01

Buildings are normally designed according to an indoor temperature level of +20 deg C and to a certain ventilation rate, which depends on the activities in the building. When normal use has been interrupted and the building is left totally unheated, the indoor conditions will follow the outdoor conditions with a certain lag depending on the structures of the building and the amount of ventilation. The lowering of a room temperature increases the risk of mould and damage to structures. The research work was divided into the theoretical part and the field measurements. The objective of the research was to increase our knowledge of the thermal and moisture technical behaviour of unheated buildings, to determine the suitable methods for ensuring the preservation of buildings and their efficiency, and to develop guidelines for selecting different methods and maintenance of buildings. In the theoretical part of the research both analytical and numerical calculation programs were developed. The analytical method is based on the thermostability theory of a room and the numerical method on heat and moisture balance equations of the building. In the numerical calculation program HMTB finite difference and element methods were exploited. The accuracy of the calculation methods was compared with the field measurement results. The field measurements were carried out in eight buildings, which consisted of heated office buildings and unheated farm houses and museum buildings. The measurements were carried out during 1997 and 1998. The annual temperature range indoors in the unheated buildings was from -15 deg C to 27 deg C and the relative humidity range from 30% to 98%. In the heated buildings relative humidity was lower. The highest levels of relative humidity in the unheated buildings were in winter and in the heated buildings in autumn. The climatic differences between districts were great. Heavy rain periods increased the moisture level of indoor air by about 10 %. The risk

Low air exchange rate causes high indoor radon concentration in energy-efficient buildings.

Science.gov (United States)

Vasilyev, A V; Yarmoshenko, I V; Zhukovsky, M V

2015-06-01

Since 1995, requirements on energy-efficient building construction were established in Russian Building Codes. In the course of time, utilisation of such technologies became prevailing, especially in multi-storey building construction. According to the results of radon survey in buildings constructed meeting new requirements on energy efficiency, radon concentration exceeds the average level in early-constructed buildings. Preponderance of the diffusion mechanism of radon entry in modern multi-storey buildings has been experimentally established. The experimental technique of the assessment of ventilation rate in dwellings under real conditions was developed. Based on estimates of average ventilation rate, it was approved that measures to increase energy efficiency lead to reduction in ventilation rate and accumulation of higher radon concentrations indoors. Obtained ventilation rate values have to be considered as extremely low. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Sealed Crawl Spaces with Integrated Whole-House Ventilation in a Cold Climate

Energy Technology Data Exchange (ETDEWEB)

Zoeller, William [Consortium for Advanced Residential Buildings, Norwalk, CT (United States); Williamson, James [Consortium for Advanced Residential Buildings, Norwalk, CT (United States); Puttagunta, Srikanth [Consortium for Advanced Residential Buildings, Norwalk, CT (United States)

2015-07-01

One method of code-compliance for crawlspaces is to seal and insulate the crawlspace, rather than venting to the outdoors. However, codes require mechanical ventilation; either via conditioned supply air from the HVAC system, or a continuous exhaust ventilation strategy. As the CARB's building partner, Ithaca Neighborhood Housing Services, intended to use the unvented crawlspace in a recent development, CARB was interested in investigating a hybrid ventilation method that includes the exhaust air from the crawlspace as a portion of an ASHRAE 62.2 compliant whole-house ventilation strategy. This hybrid ventilation method was evaluated through a series of long-term monitoring tests that observed temperature, humidity, and pressure conditions through the home and crawlspace.

Harnessing natural ventilation benefits.

Science.gov (United States)

O'Leary, John

2013-04-01

Making sure that a healthcare establishment has a good supply of clean fresh air is an important factor in keeping patients, staff, and visitors, free from the negative effects of CO2 and other contaminants. John O'Leary of Trend Controls, a major international supplier of building energy management solutions (BEMS), examines the growing use of natural ventilation, and the health, energy-saving, and financial benefits, that it offers.

Improving performance of HVAC systems to reduce exposure to aerosolized infectious agents in buildings; recommendations to reduce risks posed by biological attacks.

Science.gov (United States)

Hitchcock, Penny J; Mair, Michael; Inglesby, Thomas V; Gross, Jonathan; Henderson, D A; O'Toole, Tara; Ahern-Seronde, Joa; Bahnfleth, William P; Brennan, Terry; Burroughs, H E Barney; Davidson, Cliff; Delp, William; Ensor, David S; Gomory, Ralph; Olsiewski, Paula; Samet, Jonathan M; Smith, William M; Streifel, Andrew J; White, Ronald H; Woods, James E

2006-01-01

The prospect of biological attacks is a growing strategic threat. Covert aerosol attacks inside a building are of particular concern. In the summer of 2005, the Center for Biosecurity of the University of Pittsburgh Medical Center convened a Working Group to determine what steps could be taken to reduce the risk of exposure of building occupants after an aerosol release of a biological weapon. The Working Group was composed of subject matter experts in air filtration, building ventilation and pressurization, air conditioning and air distribution, biosecurity, building design and operation, building decontamination and restoration, economics, medicine, public health, and public policy. The group focused on functions of the heating, ventilation, and air conditioning systems in commercial or public buildings that could reduce the risk of exposure to deleterious aerosols following biological attacks. The Working Group's recommendations for building owners are based on the use of currently available, off-the-shelf technologies. These recommendations are modest in expense and could be implemented immediately. It is also the Working Group's judgment that the commitment and stewardship of a lead government agency is essential to secure the necessary financial and human resources and to plan and build a comprehensive, effective program to reduce exposure to aerosolized infectious agents in buildings.

Residential ventilation standards scoping study

Energy Technology Data Exchange (ETDEWEB)

McKone, Thomas E.; Sherman, Max H.

2003-10-01

The goals of this scoping study are to identify research needed to develop improved ventilation standards for California's Title 24 Building Energy Efficiency Standards. The 2008 Title 24 Standards are the primary target for the outcome of this research, but this scoping study is not limited to that timeframe. We prepared this scoping study to provide the California Energy Commission with broad and flexible options for developing a research plan to advance the standards. This document presents the findings of a scoping study commissioned by the Public Interest Energy Research (PIER) program of the California Energy Commission to determine what research is necessary to develop new residential ventilation requirements for California. This study is one of three companion efforts needed to complete the job of determining the ventilation needs of California residences, determining the bases for setting residential ventilation requirements, and determining appropriate ventilation technologies to meet these needs and requirements in an energy efficient manner. Rather than providing research results, this scoping study identifies important research questions along with the level of effort necessary to address these questions and the costs, risks, and benefits of pursuing alternative research questions. In approaching these questions and corresponding levels of effort, feasibility and timing were important considerations. The Commission has specified Summer 2005 as the latest date for completing this research in time to update the 2008 version of California's Energy Code (Title 24).

A prospective evaluation of ventilator-associated conditions and infection-related ventilator-associated conditions.

Science.gov (United States)

Boyer, Anthony F; Schoenberg, Noah; Babcock, Hilary; McMullen, Kathleen M; Micek, Scott T; Kollef, Marin H

2015-01-01

The Centers for Disease Control and Prevention has shifted policy away from using ventilator-associated pneumonia (VAP) and toward using ventilator-associated conditions (VACs) as a marker of ICU quality. To date, limited prospective data regarding the incidence of VAC among medical and surgical ICU patients, the ability of VAC criteria to capture patients with VAP, and the potential clinical preventability of VACs are available. This study was a prospective 12-month cohort study (January 2013 to December 2013). We prospectively surveyed 1,209 patients ventilated for ≥ 2 calendar days. Sixty-seven VACs were identified (5.5%), of which 34 (50.7%) were classified as an infection-related VAC (IVAC) with corresponding rates of 7.0 and 3.6 per 1,000 ventilator days, respectively. The mortality rate of patients having a VAC was significantly greater than that of patients without a VAC (65.7% vs 14.4%, P VACs included IVACs (50.7%), ARDS (16.4%), pulmonary edema (14.9%), and atelectasis (9.0%). Among IVACs, 44.1% were probable VAP and 17.6% were possible VAP. Twenty-five VACs (37.3%) were adjudicated to represent potentially preventable events. Eighty-six episodes of VAP occurred in 84 patients (10.0 of 1,000 ventilator days) during the study period. The sensitivity of the VAC criteria for the detection of VAP was 25.9% (95% CI, 16.7%-34.5%). Although relatively uncommon, VACs are associated with greater mortality and morbidity when they occur. Most VACs represent nonpreventable events, and the VAC criteria capture a minority of VAP episodes.

Building a wave energy policy focusing on innovation, manufacturing and deployment

International Nuclear Information System (INIS)

Dalton, G.; Gallachoir, B.P.O.

2010-01-01

The Irish Government has set a goal to make Ireland a world leader for research, development and deployment of ocean energy technologies. Ireland has a wave energy resource of 21 TWh and an ambition is to achieve at least 500 MW installed generating capacity from ocean energy by 2020. This paper investigates what is required to move from ambition to delivery. A successful wave energy strategy will require focused policies that will stimulate innovation to develop the technologies, manufacturing to produce the devices and deployment to build the required wave power plants. The paper draws on the successful policies in Ireland that have stimulated each of these dimensions, albeit for different sectors. From 2004 to 2008, successful policies in (ICT and biotech) innovation led to an increase in Ireland's Innovation Index score from 0.48 to 0.53. The policy focus on (food and pharmaceuticals) manufacturing in Ireland resulted in high levels of economic growth over the period 1998-2002, reaching >10% GDP growth levels per annum, and full employment. Successful wind energy policies deployment has accelerated rapidly since 2003 and reached 1.2 GW installed capacity in 2009 representing 15% of Ireland's total installed capacity. The paper draws on appropriate elements of these policies to build a successful wave energy policy for Ireland. It also draws on the successful policies adopted in Denmark for innovation, manufacturing and deployment of wind energy. The Danish wind turbine manufacturers hold a world market share of approximately 40%. The paper proposes establishing a wave energy strategy group to develop an action plan to deliver the 500 MW. It also proposes a novel extension of corporate tax specifically for wave energy companies, an initial 30% capital grant scheme for wave energy developers, a grid code for wave energy devices and fast tracking of planning decisions through an amended approach to strategic infrastructure. (author)

Ventilator-driven xenon ventilation studies

International Nuclear Information System (INIS)

Chilcoat, R.T.; Thomas, F.D.; Gerson, J.I.

1984-01-01

A modification of a common commercial Xe-133 ventilation device is described for mechanically assisted ventilation imaging. The patient's standard ventilator serves as the power source controlling the ventilatory rate and volume during the xenon study, but the gases in the two systems are not intermixed. This avoids contamination of the ventilator with radioactive xenon. Supplemental oxygen and positive end-expiratory pressure (PEEP) are provided if needed. The system can be converted quickly for conventional studies with spontaneous respiration

Ventilation-air conditioner system in nuclear power plant

International Nuclear Information System (INIS)

Kubota, Ryuji; Sugisaki, Toshihiko.

1989-01-01

This invention concerns a ventilation-air conditioner system which enables, upon occurrence of accidents in a nuclear power plant, continuous operation for other adjacent nuclear power plants with no effect of accidents. Air supply system and exhaust system are operated during usual operaiton. If loss of coolants accidents should occur in an adjacent nuclear power plants, operation is switched from ventilation operaiton to the operation of re-cycling system based on an AND logic of three signals, that is, a pressure HIGH signal for the reactor container, a water level LOW signal for the reactor and a radioactivity signal of the ventilation-air conditioner sytem on the side of air supply in the nuclear power plant. Thus, nuclear reactor buildings of the nuclear power plant are from the external atmosphere. Therefore, the radioactivity HIGH signal for switching to the emergency air conditioner system of the nuclear power plant is not actuated due to the loss of coolant accidents in the adjacent nuclear power plant. In addition, since the atmospheric temperature in the nuclear reactor building can be maintained by a cooling device disposed to the recycling system, reactor shutdown can be prevented. (I.S.)

Building a New South Africa Volume 1 : Economic Policy | IDRC ...

International Development Research Centre (IDRC) Digital Library (Canada)

Couverture du livre Building a New South Africa Volume 1 : Economic Policy. Editor(s): ... Findings from an IDRC-supported program figure prominently at the annual conference of McGill's Institute for the Study of International Development. ... Special journal issue highlights IDRC-supported findings on women's paid work.

BSim Models for 2 Case-studies of Naturally and Mechanically Ventilated Daycare Institutions

DEFF Research Database (Denmark)

Larsen, Olena Kalyanova; Heiselberg, Per

and conclusions derived from the results of simulation of two different institutions in various operational modes. Thermal models are prepared for two buildings, which are: SFO Nymarken in Kerterminde and SFO Spirehuset in Hirtshals. The main operational principles in these buildings are significantly different......, as SFO Nymarken is mechanically ventilated and SFO Spirehuset is naturally ventilated. All of the simulations were carried in BSim, and all of the models are simulated in the current version of BSim, which is version 6,8,9,8....

Impact of Air Distribution on Heat Transfer during Night-Time Ventilation

DEFF Research Database (Denmark)

Heiselberg, Per; Artmann, Nikolai; Jensen, Rasmus Lund

2009-01-01

Passive cooling by night-time ventilation is seen as a promising approach for energy efficient cooling of buildings. However, uncertainties in prediction of cooling potential and consequenses for thermal comfort restrain architects and engineers from applying this technique. Heat transfer...... at internal room surfaces determines the performance of night-time ventilation. In order to improve predictability, heat transfer mechanism in case of either mixing or displacement ventilation has been investigated in a full scale test room with an exposed ceiling as the dominating thermal mass. The influence...... of air distribution principle, air flow rate and inlet air temperature were investigated. Results show that for low air flow rates displacement ventilation is more efficient than mixing ventilation. For higher airflow rates the air jet flowing along the ceiling has a significant effect, and mixing...

Anaesthesia ventilators

Directory of Open Access Journals (Sweden)

Rajnish K Jain

2013-01-01

Full Text Available Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV. PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits.

Anaesthesia ventilators.

Science.gov (United States)

Jain, Rajnish K; Swaminathan, Srinivasan

2013-09-01

Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV). PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits.

Anaesthesia ventilators

Science.gov (United States)

Jain, Rajnish K; Swaminathan, Srinivasan

2013-01-01

Anaesthesia ventilators are an integral part of all modern anaesthesia workstations. Automatic ventilators in the operating rooms, which were very simple with few modes of ventilation when introduced, have become very sophisticated with many advanced ventilation modes. Several systems of classification of anaesthesia ventilators exist based upon various parameters. Modern anaesthesia ventilators have either a double circuit, bellow design or a single circuit piston configuration. In the bellows ventilators, ascending bellows design is safer than descending bellows. Piston ventilators have the advantage of delivering accurate tidal volume. They work with electricity as their driving force and do not require a driving gas. To enable improved patient safety, several modifications were done in circle system with the different types of anaesthesia ventilators. Fresh gas decoupling is a modification done in piston ventilators and in descending bellows ventilator to reduce th incidence of ventilator induced volutrauma. In addition to the conventional volume control mode, modern anaesthesia ventilators also provide newer modes of ventilation such as synchronised intermittent mandatory ventilation, pressure-control ventilation and pressure-support ventilation (PSV). PSV mode is particularly useful for patients maintained on spontaneous respiration with laryngeal mask airway. Along with the innumerable benefits provided by these machines, there are various inherent hazards associated with the use of the ventilators in the operating room. To use these workstations safely, it is important for every Anaesthesiologist to have a basic understanding of the mechanics of these ventilators and breathing circuits. PMID:24249886

Towards passive house standards in school buildings. Maela smart building - final report; Mot passivhusstandard i undervisningsbygg. Maela smartbygg - sluttrapport

Energy Technology Data Exchange (ETDEWEB)

Wachenfeldt, Bjoern Jenssen; Dokka, Tor Helge

2008-07-01

SINTEF has in cooperation with the projecting group for Maela School, worked towards smart and general concepts to achieve good comfort with low energy consumption, low environmental impact and low investments. The project is called 'Maela smart building'. Based on conceptual solutions chosen for Maela School, this might be one of the leading school buildings in concern of energy efficiency. To be sure of achieving the target of needed energy to be less than 80 kWh/m{sub 2}, this assumes that the solutions satisfies the demands elaborated with basis in the energy target for the building together with heating and ventilation technical outfit run optimally. If the real consumption shall decrease towards calculated energy needs, the users have to be conscious not to contribute in wasting energy. Further the management of heat and ventilation has to function optimally, the setpoint for heating and ventilation has to be precise. In addition the operators have to have insight in how a building like this functions and the right skills to run it correct. Emphasis on alternatives contributing positively to architecture and good indoor environment in addition to focus on energy efficiency were considered for technical designing of the conceptual heat and ventilation solutions. Generally the need for ventilation channels is reduced to a minimum and the mechanical ventilation is dimensioned considering air quality. Thermic comfort is secured by means of passive attempt such as natural ventilation, sun screening and exploitation of thermic substance in ceiling, walls and floor. Choice of windows and walls with translucent isolation implied some increased risk for overheated teaching wings in second floor in warm and sunny periods. Since these premises because of school vacation in summer, normally is not in use in the summer, the attempts such as sun screening, natural ventilation and night cooling (ventilation of surplus heat during nights),were considered sufficient

Modulating ventilation - low cost VAV for office buildings. [Variable Air Volume]; Modulerende ventilation - low cost VAV til kontor-bygninger. Slutrapport

Energy Technology Data Exchange (ETDEWEB)

Hoej Christensen, A.; Olsen, Hans; Drivsholm, C.

2012-02-15

The report describes a concept for renovating older existing Constant Air Volume (CAV) ventilation systems to modulating low-cost Variable Air Volume (VAV) systems. The concept is based on the total ventilated area being divided into appropriate indoor climate zones, which can cover from one to several offices with similar climate needs. For this initial climate assessment two relatively ''simple'' tools were developed that can estimate the temperature level in one room from the ventilation airflow, heat loads, etc.: - BSimFast (24-hour mean temperature calculation according to SBI-196, 2000); - BSimLight (Temperature simulation based on Danvak Textbook of Heat and Climate Technology). The concept of 'one room' can also be extended to 'one zone' with appropriate assumptions. However, only one mean room temperature is calculated. The different climate zones were equipped with Halton HFB control unit at the air supply and exhaust side. The project the following feedback options were used: - HFB unit's damper opening degree (0 to 90 degrees); - HFB unit's current flow; - HFB unit's exhaust temperature; and feedback from: - Frequency transformer (fan speed); - The central static duct pressure at the ventilation unit. In the project a control algorithm is developed that ensures a robust control of the entire ventilation system without adverse cyclic variations, based among other things on the exhaust temperature for each climate zone, and with the requirement that at least one throttle valve is always at least 80% open. It turned out that information on the current partial air volumes was necessary in addition to the individual throttle settings. Otherwise, a cyclic variations could not be controlled..Thus, it was the exhaust temperature from individual climate zones that defined the respective volumes of air. The concept was implemented on a complete CAV system and on part of a large CAV system, respectively. (LN)

Risk Factors in Heating, Ventilating, and Air-Conditioning Systemsfor Occupant Symptoms in U.S. Office Buildings: the EPA BASE Study

Energy Technology Data Exchange (ETDEWEB)

Mendell, M.J.; Lei-Gomez, Q.; Mirer, A.; Seppanen, O.; Brunner, G.

2006-10-01

Nonspecific building-related symptoms among occupants of modern office buildings worldwide are common and may be associated with important reductions in work performance, but their etiology remains uncertain. Characteristics of heating, ventilating, and air-conditioning (HVAC) systems in office buildings that increase risk of indoor contaminants or reduce effectiveness of ventilation may cause adverse exposures and subsequent increase in these symptoms among occupants. We analyzed data collected by the U.S. EPA from a representative sample of 100 large U.S. office buildings--the Building Assessment and Survey Evaluation (BASE) study--using multivariate logistic regression models with generalized estimating equations adjusted for potential personal and building confounders. We estimated odds ratios (ORs) and 95% confidence intervals (CIs) for associations between seven building-related symptom outcomes and selected HVAC system characteristics. Among factors of HVAC design or configuration: Outdoor air intakes less than 60 m above the ground were associated with approximately doubled odds of most symptoms assessed. Sealed (non-operable) windows were associated with increases in skin and eye symptoms (ORs= 1.9, 1.3, respectively). Outdoor air intake without an intake fan was associated with an increase in eye symptoms (OR=1.7). Local cooling coils were associated with increased headache (OR=1.5). Among factors of HVAC condition, maintenance, or operation: the presence of humidification systems in good condition was associated with an increase in headache (OR=1.4), whereas the presence of humidification systems in poor condition was associated with increases in fatigue/difficulty concentrating, as well as upper respiratory symptoms (ORs=1.8, 1.5). No regularly scheduled inspections for HVAC components was associated with increased eye symptoms, cough and upper respiratory symptoms (ORs=2.2, 1.6, 1.5). Less frequent cleaning of cooling coils or drip pans was associated

Ammonia emissions in tunnel-ventilated broiler houses

Directory of Open Access Journals (Sweden)

KAO Lima

2011-12-01

Full Text Available Gas production in broiler houses and their emissions are closely related to the microclimate established inside the house according to air temperature, humidity, and velocity. Therefore, the internal house environment is influenced by building typology and ventilation system. The objective of the present study was to evaluate ammonia emission rates in broiler houses equipped with different ventilation systems (negative or positive pressure and litter conditions (new or built-up. The environment of six commercial broiler houses was evaluated internal and external NH3 concentrations. Ventilation rates were recorded to estimate ammonia emission rates. The efficiency of circulation and exhaust fans was assessed, and higher ventilation rates were determined in negative-pressure houses due to the higher flow of the fans. Houses with new litter increased ammonia emission rates along the rearing period, indicating the relationship between gas emissions, bird age and ventilation rates, and presented a typical curve of NH3 emission increase. Negative-pressure houses with built-up litter presented higher emission rates during the first rearing week due to the high NH3 concentration during the brooding period, when the ventilation rates required to maintain chick thermal comfort are low. Although the results of the present study indicate an advantage of the positive-pressure systems as to gas emissions, further research is needed reduce gas emissions in broiler houses with negative-pressure systems.

Air Distribution in a Room and Design Considerations of Mixing Ventilation by Flow Elements

DEFF Research Database (Denmark)

Nielsen, Peter V.; Jensen, Rasmus Lund; Pedersen, D. N.

2001-01-01

The paper shows detailed measurements of the air distribution in a room ventilated by mixing ventilation according to the specifications given by the International Energy Agency work. (Energy Conservation in Buildings and Community Systems Programme, Annex 20). It describes a number of flow...

Sick building syndrome

Energy Technology Data Exchange (ETDEWEB)

Eyre, S

1990-10-01

Recently, there has been an upsurge in public awareness about the hazards of indoor air pollution. It is documented that respiratory tract infections, a common result of poor air quality, account for approximately 150 million lost work days, $15-billion of direct medical costs, and at least $59-billion of indirect costs of absenteeism per year. Indoor air pollutants result from a number of different sources including common office supplies and equipment, cleaning supplies, pesticides, clothing, furnishings, draperies and carpets. A recent summary of findings by Healthy Buildings International has found the three most common problems to be: poor ventilation, inadequate filtration and lack of hygiene. Only 25% of the buildings studied were well ventilated and 75% of the problems with contaminated air were due to ignorance of correct operating practices. Currently, there are no uniformly accepted regulations for environmental quality in buildings in Canada. Some approaches to this problem are discussed and it is noted that the solution to indoor air quality problems is prevention or proactive monitoring. The key to a successful monitoring program is that improvements made by implementing remedial actions can be quantified, and to place the focus of the program on the ventilation system. 1 fig.

Note on protection offered by ventilation systems in the event of a nuclear reactor accident

International Nuclear Information System (INIS)

Wayland, J.R.; McGrath, P.E.

1976-05-01

A brief review of the protection offered by natural and forced ventilation systems in buildings to an atmospheric release of radioactive material is given. The protection to be gained by using the internal ventilation system is estimated

Application of PCM energy storage in combination with night ventilation for space cooling

International Nuclear Information System (INIS)

Barzin, Reza; Chen, John J.J.; Young, Brent R.; Farid, Mohammed M.

2015-01-01

Highlights: • Night ventilation were tested in combination with PCM-impregnated gypsum boards. • The Price-based method were experimentally used to perform peak load shifting. • Importance of the application of a smart control were experimentally investigated. • A cost and energy saving up to 93% and 92% per day respectively were achieved. - Abstract: In recent years, as a result of the continuous increase in energy demand, the use of energy storage has become increasingly important. To address this problem, the application of phase change materials (PCM) in buildings has received attention because of their high energy storage density and their ease of incorporation in building envelopes. Despite large experimental works conducted on the application phase change materials in buildings, there is very little work done on this application in combination with night ventilation. In this study, the application of night ventilation in combination with PCM-impregnated gypsum boards for cooling purposes was experimentally investigated. Two identical test huts equipped with “smart” control systems were used for testing the concept. One hut was constructed using impregnated gypsum boards, while the other hut was finished with ordinary gypsum board. Initially an air conditioning (AC) unit, without night ventilation, was used in both huts to charge the PCM during low peak period, showing very little savings in electricity. However, when night ventilation was used to charge the PCM instead, a weekly electricity saving of 73% was achieved.

Energy performance of a ventilated façade by simulation with experimental validation

International Nuclear Information System (INIS)

Aparicio-Fernández, Carolina; Vivancos, José-Luis; Ferrer-Gisbert, Pablo; Royo-Pastor, Rafael

2014-01-01

A model for a building with ventilated façade was created using the software tool TRNSYS, version 17, and airflow parameters were simulated using TRNFlow. The results obtained with the model are compared and validated with experimental data. The temperature distribution along the air cavity was analysed and a chimney effect was observed, which produced the highest temperature gradient on the first floor. The heat flux of the external wall was analysed, and greater temperatures were observed on the external layer and inside the cavity. The model allows to calculate the energy demand of the building façade proposing and evaluating passive strategies. The corresponding office building for computer laboratories located in Valencia (Spain), was monitored for a year. The thermal behaviour of the floating external sheet was analysed using an electronic panel designed for the reading and storage of data. A feasibility study of the recovery of hot air inside the façade into the building was performed. The results obtained showed a lower heating demand when hot air is introduced inside the building, increasing the efficiency of heat recovery equipment. - Highlights: •An existing office building was monitored for a year. •A model of a ventilated façade by TRNSYS simulation tool was validated. •Air flow parameters inside the ventilated façade were identified. •Recovery of the hot air inside the façade for input into the building was studied

Building emerging leaders in communications policy in Africa and Asia

International Development Research Centre (IDRC) Digital Library (Canada)

Among the activities supported will be tutorials, conferences, development of a social media-based platform for practitioners, and organization of a workshop on big data and development. The project is expected to build a new cohort of communications policy leaders and provide a nuanced understanding of how to ...

Analysing policy interactions for promoting energy efficiency in the Hellenic sectors of buildings and transport

OpenAIRE

Dr. Popi KONIDARI; Mrs. Anna FLESSA; Ms. Aliki-Nefeli MAVRAKI; Ms. Eleni-Danai MAVRAKI

2016-01-01

Policy interactions are important parameters for the successful implementation of policies, measures and policy instruments. The parallel implementation of a number of policy instruments has the potential to create synergies or conflicts that maximize or prevent the achievement of their anticipated outcomes. This paper analyses three cases of policy interactions between two policy instruments for promoting even more the energy efficiency outcomes in Greece for two sectors, buildings and trans...

Diffusion and Evaporation-Controlled Emission in Ventilated Rooms

DEFF Research Database (Denmark)

Topp, Claus

and sources. This work provides an investigation based on fundamental fluid dynamics and mass transfer theory to obtain a general understanding of the mechanisms involved in the emission from building materials in ventilated rooms. In addition, a generally applicable model for prediction of surface emission...... is proposed. The interest has been focused on the emission of vapours and gases as no particulate emissions have been considered. The methods used are numerical calculations by computational fluid dynamics (CFD) and full-scale laboratory experiments. It was found that the emission is a strong function of air......In emission studies reported in literature little effort has been made to investigate the emission from building materials in ventilated enclosures from a fluid dynamics point of view. Furthermore, most of the existing emission models are empirical relations that are based on specific pollutants...

Effects of natural and forced basement ventilation on radon levels in single-family dwellings. Final report, May 90-Aug 91

International Nuclear Information System (INIS)

Cavallo, A.; Gadsby, K.; Reddy, T.A.

1992-06-01

The report gives, for the first time, results of an extensive study of the effect of ventilation on radon concentrations and radon entry rate in a single-family dwelling. Measurements of radon concentrations, building dynamics, and environmental parameters made in Princeton University research houses over several seasons and under different building operating conditions show the functional dependence of radon entry rate on basement depressurization. The work clarifies the role of natural ventilation in reducing indoor radon concentrations. The work shows conclusively that natural ventilation can decrease radon levels two ways: (1) by simple dilution, and (2) by providing a pressure break (defined as any opening in the building shell that reduces the outdoor/indoor differential pressure). This reduces building depressurization and thus the amount of radon-contaminated soil gas that is drawn into the building

Evaluation of ventilators for mouthpiece ventilation in neuromuscular disease.

Science.gov (United States)

Khirani, Sonia; Ramirez, Adriana; Delord, Vincent; Leroux, Karl; Lofaso, Frédéric; Hautot, Solène; Toussaint, Michel; Orlikowski, David; Louis, Bruno; Fauroux, Brigitte

2014-09-01

Daytime mouthpiece ventilation is a useful adjunct to nocturnal noninvasive ventilation (NIV) in patients with neuromuscular disease. The aims of the study were to analyze the practice of mouthpiece ventilation and to evaluate the performance of ventilators for mouthpiece ventilation. Practice of mouthpiece ventilation was assessed by a questionnaire, and the performance of 6 home ventilators with mouthpiece ventilation was assessed in a bench test using 24 different conditions per ventilator: 3 mouthpieces, a child and an adult patient profile, and 4 ventilatory modes. Questionnaires were obtained from 30 subjects (mean age 33 ± 11 y) using NIV for 12 ± 7 y. Fifteen subjects used NIV for > 20 h/day, and 11 were totally ventilator-dependent. The subject-reported benefits of mouthpiece ventilation were a reduction in dyspnea (73%) and fatigue (93%) and an improvement in speech (43%) and eating (27%). The bench study showed that none of the ventilators, even those with mouthpiece ventilation software, were able to deliver mouthpiece ventilation without alarms and/or autotriggering in each condition. Alarms and/or ineffective triggering or autotriggering were observed in 135 of the 198 conditions. The occurrence of alarms was more common with a large mouthpiece without a filter compared to a small mouthpiece with a filter (P ventilator. Subjects are satisfied with mouthpiece ventilation. Alarms are common with home ventilators, although less common in those with mouthpiece ventilation software. Improvements in home ventilators are needed to facilitate the expansion of mouthpiece ventilation. Copyright © 2014 by Daedalus Enterprises.

Evaluation of the indoor air quality minimum ventilation rate procedure for use in California retail buildings.

Science.gov (United States)

Dutton, S M; Mendell, M J; Chan, W R; Barrios, M; Sidheswaran, M A; Sullivan, D P; Eliseeva, E A; Fisk, W J

2015-02-01

This research assesses benefits of adding to California Title-24 ventilation rate (VR) standards a performance-based option, similar to the American Society of Heating, Refrigerating, and Air Conditioning Engineers 'Indoor Air Quality Procedure' (IAQP) for retail spaces. Ventilation rates and concentrations of contaminants of concern (CoC) were measured in 13 stores. Mass balance models were used to estimate 'IAQP-based' VRs that would maintain concentrations of all CoCs below health- or odor-based reference concentration limits. An intervention study in a 'big box' store assessed how the current VR, the Title 24-prescribed VR, and the IAQP-based VR (0.24, 0.69, and 1.51 air changes per hour) influenced measured IAQ and perceived of IAQ. Neither current VRs nor Title 24-prescribed VRs would maintain all CoCs below reference limits in 12 of 13 stores. In the big box store, the IAQP-based VR kept all CoCs below limits. More than 80% of subjects reported acceptable air quality at all three VRs. In 11 of 13 buildings, saving energy through lower VRs while maintaining acceptable IAQ would require source reduction or gas-phase air cleaning for CoCs. In only one of the 13 retail stores surveyed, application of the IAQP would have allowed reduced VRs without additional contaminant-reduction strategies. Published 2014. This article is a U.S. Government work and is in the public domain in the USA.

Airflow and radon transport modeling in four large buildings

International Nuclear Information System (INIS)

Fan, J.B.; Persily, A.K.

1995-01-01

Computer simulations of multizone airflow and contaminant transport were performed in four large buildings using the program CONTAM88. This paper describes the physical characteristics of the buildings and their idealizations as multizone building airflow systems. These buildings include a twelve-story multifamily residential building, a five-story mechanically ventilated office building with an atrium, a seven-story mechanically ventilated office building with an underground parking garage, and a one-story school building. The air change rates and interzonal airflows of these buildings are predicted for a range of wind speeds, indoor-outdoor temperature differences, and percentages of outdoor air intake in the supply air Simulations of radon transport were also performed in the buildings to investigate the effects of indoor-outdoor temperature difference and wind speed on indoor radon concentrations

VRML Programs for Room Ventilation Applications

DEFF Research Database (Denmark)

Nielsen, Anker

Cheap 3D models for visualization of room ventilation applications are now available. VRML (Virtu~l Reality Modelling Language) is found to be a good format to describe buildings, rooms and furniture. A 3D model in VRML can be placed on a World Wide Web (www) page and others can see the model...

Indoor Chemistry: Materials, Ventilation Systems, and Occupant Activities

Energy Technology Data Exchange (ETDEWEB)

Morrison, G.C.; Corsi, R.L.; Destaillats, H.; Nazaroff, W.W.; Wells, J.R.

2006-05-01

Chemical processes taking place in indoor environments can significantly alter the nature and concentrations of pollutants. Exposure to secondary contaminants generated in these reactions needs to be evaluated in association with many aspects of buildings to minimize their impact on occupant health and well-being. Focusing on indoor ozone chemistry, we describe alternatives for improving indoor air quality by controlling chemical changes related to building materials, ventilation systems, and occupant activities.

Building Capacity in Health Systems and Policy Analysis in sub ...

International Development Research Centre (IDRC) Digital Library (Canada)

Building Capacity in Health Systems and Policy Analysis in sub-Saharan Africa. Since 2005, the Bill and Melinda Gates Foundation has been financing the master's program in health and population at the Institut supérieure des sciences de la population (ISSP), Université de Ouagadougou, Burkina Faso. However, after ...

Ventilation and ventilation/perfusion ratios

International Nuclear Information System (INIS)

Valind, S.O.

1989-01-01

The thesis is based on five different papers. The labelling of specific tracer compounds with positron emitting radionuclides enables a range of structural, physiological and biochemical parameters in the lung to be measured non-invasively, using positron emission tomography. This concept affords a unique opportunity for in vivo studies of different expressions of pulmonary pathophysiology at the regional level. The present thesis describes the application of positron emission tomography to the measurements of ventilation and ventilation/perfusion ratios using inert gas tracers, neon-19 and nitrogen-13 respectively. The validity of the methods applied was investigated with respect to the transport of inert gas tracers in the human lung. Both ventilation and the ventilation/perfusion ratio may be obtained with errors less than 10 % in the normal lung. In disease, however, errors may increase in those instances where the regional ventilation is very low or the intra-regional gas flow distribution is markedly nonuniform. A 2-3 fold increase in ventilation was demonstrated in normal nonsmoking subjects going from ventral to dorsal regions in the supine posture. These large regional differences could be well explained by the intrinsic elastic properties of lung tissue, considering the gravitational gradient in transpulmonary pressure. In asymptomatic smokers substantial regional ventilatroy abnormalities were found whilst the regional gas volume was similar in smokers and nonsmokers. The uncoupling between ventilation and gas volume probably reflects inflammatory changes in the airways. The regional differences in dV/dt/dQ/dt were relatively small and blood flow was largely matched to ventilation in the supine posture. However, small regions of lung with very low ventilation, unmatched by blood flow commonly exists in the most dependent parts of the lung in both smokers and nonsmokers. (29 illustrations, 7 tables, 113 references)

Determination of utilizable wind energy for indoor ventilation in ...

African Journals Online (AJOL)

Journal of the Nigerian Association of Mathematical Physics ... Determination of utilizable wind energy for indoor ventilation in buildings across selected locations in Nigeria ... Weibull's distribution function was used for modeling of wind speed ...

Air distribution and ventilation effectiveness in an occupied room heated by warm air

DEFF Research Database (Denmark)

Krajcik, Michal; Simone, Angela; Olesen, Bjarne W.

2012-01-01

and at different simulated outside conditions, internal heat gains and air change rates. Floor heating was also simulated and compared with the warm air heating system. Vertical air temperature profiles, air velocity profiles and equivalent temperatures were derived in order to describe the thermal environment...... floor heating system was simulated, the cooler ventilation air introduced to the room mixed well and created uniform conditions with a ventilation effectiveness of about 1.......Air distribution, ventilation effectiveness and thermal environment were experimentally studied in a simulated room in a low-energy building heated and ventilated by warm air supplied by a mixing ventilation system. Measurements were performed for various positions of the air terminal devices...

Implications in estimation of indoor thoron levels: season and ventilation effects

International Nuclear Information System (INIS)

Chauhan, R.P.; Amit Kumar

2015-01-01

The measurement of radon and thoron in dwellings and workplaces are most important for general public health point. Due to short half life of thoron, sometimes its contribution to radiation doses is assumed to be negligible, but their role is important for areas containing higher thorium content in soil and building materials. The thoron levels in dwellings were determined by various SSNTD detector using different cup geometry and dimensions along with bare mode in past at National and International level. These exercises were carried out in dwellings constructed with different building materials, different ventilation rates and seasons. Most of the times the results of radon and thoron levels were found same in spite of having different diffusion length in air due to different half life. This causes increase in uncertainty in measurement of thoron levels in different season and ventilation. Thus the problem of relative variation of thoron levels in different season and ventilation still exist in radiation field. In this work the measurement of indoor thoron levels from some selected dwelling having different ventilation and in different seasons using Pin hole based radon thoron dosimeters are reported. The results show that indoor thoron value is slightly lower in case of dwellings with poor ventilation, which is contrary to the results published in literature. An effort was made to explain the variation of thoron level under different season and ventilation. Some protocol suggestions are also given at the end of this work for future reference to carry out the measurement and mapping of indoor thoron. (author)

Seismic evaluation of the LLNL plutonium facility (Building 332)

International Nuclear Information System (INIS)

Hall, W.J.; Sozen, M.A.

1982-03-01

The expected performance of the Lawrence Livermore National Laboratory (LLNL) Plutonium Facility (Building 332) subjected to earthquake ground motion has been evaluated. Anticipated behavior of the building, glove boxes, ventilation system and other systems critical for containment of plutonium is described for three severe postulated earthquake excitations. Based upon this evaluation, some damage to the building, glove boxes and ventilation system would be expected but no collapse of any structure is anticipated as a result of the postulated earthquake ground motions

The Effects of Void on Natural Ventilation Performance in Multi-Storey Housing

Directory of Open Access Journals (Sweden)

Fakhriah Muhsin

2016-08-01

Full Text Available Enhancing natural ventilation performance in multi-storey housing is very important for the living environment in terms of health and thermal comfort purposes. One of the most important design strategies to enhance natural ventilation in multi-storey housing is through the provision of voids. A void is a passive architectural feature, which is located in the middle of deep plan buildings. It is very crucial to consider the configurations of voids in the buildings for enhancing natural ventilation, especially for multi-storey housing. In this study, Malaysian Medium Cost Multi-Storey Housing (MMCMSH, which is an example of multi-storey housing located in a suburban area, has been selected in this study. This study aims to investigate the potential of void for enhancing natural ventilation performance in multi-storey housing by the comparison of two different void configurations. Field measurement of MMCMSH has been conducted to validate Computational Fluid Dynamic (CFD model and Atmospheric Boundary Layer (ABL is an important parameter for setting up the CFD Model’s domain. Ventilation rate (Q, which is necessary for comfort and health reasons, is an important parameter for the comparison of the different void configurations. This study revealed that the provision of void can enhance natural ventilation performance in multi-storey housing with an increase in the value of Q, from 3.44% to 40.07%, by enlarging the void’s width by 50% compared to the existing void.

Sustainable Building in China—A Green Leap Forward?

Directory of Open Access Journals (Sweden)

Jialiang Wang

2013-09-01

Full Text Available China is constructing new commercial buildings at an enormous rate—roughly 2 billion square meters per year, with considerable interest and activity in green design and construction. We review the context of commercial building design and construction in China, and look at a specific project as an example of a high performance, sustainable design, the Shenzhen Institute of Building Research (IBR. The IBR building incorporates over 40 sustainable technologies and strategies, including daylighting, natural ventilation, gray-water recycling, solar-energy generation, and highly efficient Heating Ventilation and Air Conditioning (HVAC systems. We present measured data on the performance of the building, including detailed analysis by energy end use, water use, and occupant comfort and satisfaction. Total building energy consumption in 2011 was 1151 MWh, with an Energy Use Intensity (EUI of 63 kWh/m2 (20 kBtu/ft2, which is 61% of the mean EUI value of 103 kWh/m2 (33 kBtu/ft2 for similar buildings in the region. We also comment on the unique design process, which incorporated passive strategies throughout the building, and has led to high occupant satisfaction with the natural ventilation, daylighting, and green patio work areas. Lastly we present thoughts on how the design philosophy of the IBR building can be a guide for low-energy design in different climate regions throughout China and elsewhere.

An analysis on how proposed requirements for near zero energy buildings manages PV electricity in combination with two different types of heat pumps and its policy implications – A Swedish example

International Nuclear Information System (INIS)

Thygesen, Richard; Karlsson, Björn

2017-01-01

This paper presents an analysis on how exhaust air- and ground source- heat pumps in combination with PV-systems affects the specific energy demand of buildings with the proposed Swedish near zero energy building definition and its policy implications. It also presents a method on how to estimate the contribution from the photovoltaic-system on the reduction of the specific energy demand of the building. A challenge with the proposed near zero energy building definition is that it is not clearly defined how it manages photovoltaic electricity as a mean to reduce the specific energy demand of buildings. The results suggest that the building with the ground source heat pump and heat recovery ventilation has the lowest specific energy demand. The proposed definition will give an advantage to system combinations comprised of heat pumps and PV-systems and this will lead to the possibility to build less insulated buildings with higher heat losses than for a building with a non-electrical heating system. A higher share of heat pumps can lead to lower electricity production in Sweden because of lost heating loads in district heating systems and a higher electricity demand. - Highlights: • We analyzed how the proposed Swedish NZE building definition manages PV electricity. • The building with a GSHP has the lowest specific energy demand. • Two different assumptions on the usage of PV electricity was used. • The difference between the two assumptions is 6 kWh/m"2 for both the GSHP and EAHP.

Business approach to mine air quality and ventilation

Energy Technology Data Exchange (ETDEWEB)

Byrne, M.J. [Newmont Mining Corp., Greenwood Village, CO (United States)

2009-07-01

A business approach to air quality and ventilation in mines was discussed in this presentation. Issues that were addressed included leadership approaches in bridging the gap between the visible culture of policies and procedures with invisible cultures such as norms, assumptions and beliefs. An overview of occupational safety was also presented in terms of measuring diesel particulate matter (DPM) and key DPM activities such as ventilation modeling; remote control of ventilation circuits; real-time diagnostics of engine performance through electronic control modules; personnel and equipment tracking systems; remote carbon monoxide and carbon dioxide monitoring; and semi-quantitative real-time DPM monitoring. Resources such as ventilation engineers and other professionals also contribute to key DPM activities as do experience and good practice sharing between sites. The purpose of the presentation was to determine if 160 {mu}g/m{sup 3} is an achievable number for exposure to DPM and the standard by which mines should operate globally. figs.

Energy efficiency buildings program, FY 1980

Energy Technology Data Exchange (ETDEWEB)

1981-05-01

A separate abstract was prepared on research progress in each group at LBL in the energy efficient buildings program. Two separate abstracts were prepared for the Windows and Lighting Program. Abstracts prepared on other programs are: Energy Performance of Buildings; Building Ventilation and Indoor Air Quality Program; DOE-21 Building Energy Analysis; and Building Energy Data Compilation, Analysis, and Demonstration. (MCW)

End-use energy consumption estimates for U.S. commercial buildings, 1992

Energy Technology Data Exchange (ETDEWEB)

Belzer, D.B.; Wrench, L.E.

1997-03-01

An accurate picture of how energy is used in the nation`s stock of commercial buildings can serve a variety of program planning and policy needs of the US Department of Energy, utilities, and other groups seeking to improve the efficiency of energy use in the building sector. This report describes an estimation of energy consumption by end use based upon data from the 1992 Commercial Building Energy Consumption Survey (CBECS). The methodology used in the study combines elements of engineering simulations and statistical analysis to estimate end-use intensities for heating, cooling, ventilation, lighting, refrigeration, hot water, cooking, and miscellaneous equipment. Statistical Adjusted Engineering (SAE) models were estimated by building type. The nonlinear SAE models used variables such as building size, vintage, climate region, weekly operating hours, and employee density to adjust the engineering model predicted loads to the observed consumption (based upon utility billing information). End-use consumption by fuel was estimated for each of the 6,751 buildings in the 1992 CBECS. The report displays the summary results for 11 separate building types as well as for the total US commercial building stock. 4 figs., 15 tabs.

Cool roofs in China: Policy review, building simulations, and proof-of-concept experiments

International Nuclear Information System (INIS)

Gao, Yafeng; Xu, Jiangmin; Yang, Shichao; Tang, Xiaomin; Zhou, Quan; Ge, Jing; Xu, Tengfang; Levinson, Ronnen

2014-01-01

While the concept of reflective roofing is not new to China, most Chinese cool roof research has taken place within the past decade. Some national and local Chinese building energy efficiency standards credit or recommend, but do not require, cool roofs or walls. EnergyPlus simulations of standard-compliant Chinese office and residential building prototypes in seven Chinese cities (Harbin, Changchun, Beijing, Chongqing, Shanghai, Wuhan, and Guangzhou) showed that substituting an aged white roof (albedo 0.6) for an aged gray roof (albedo 0.2) yields positive annual load, energy, energy cost, CO 2 , NO x , and SO 2 savings in all hot-summer cities (Chongqing, Shanghai, Wuhan, and Guangzhou). Measurements in an office building in Chongqing in August 2012 found that a white coating lowered roof surface temperature by about 20 °C, and reduced daily air conditioning energy use by about 9%. Measurements in a naturally ventilated factory in Guangdong Province in August 2011 showed that a white coating decreased roof surface temperature by about 17 °C, lowered room air temperature by 1–3 °C, and reduced daily roof heat flux by 66%. Simulation and experimental results suggest that cool roofs should be credited or prescribed in building energy efficiency standards for both hot summer/warm winter and hot summer/cold winter climates in China