A quantitative method for risk assessment of agriculture due to climate change

Science.gov (United States)

Dong, Zhiqiang; Pan, Zhihua; An, Pingli; Zhang, Jingting; Zhang, Jun; Pan, Yuying; Huang, Lei; Zhao, Hui; Han, Guolin; Wu, Dong; Wang, Jialin; Fan, Dongliang; Gao, Lin; Pan, Xuebiao

2018-01-01

Climate change has greatly affected agriculture. Agriculture is facing increasing risks as its sensitivity and vulnerability to climate change. Scientific assessment of climate change-induced agricultural risks could help to actively deal with climate change and ensure food security. However, quantitative assessment of risk is a difficult issue. Here, based on the IPCC assessment reports, a quantitative method for risk assessment of agriculture due to climate change is proposed. Risk is described as the product of the degree of loss and its probability of occurrence. The degree of loss can be expressed by the yield change amplitude. The probability of occurrence can be calculated by the new concept of climate change effect-accumulated frequency (CCEAF). Specific steps of this assessment method are suggested. This method is determined feasible and practical by using the spring wheat in Wuchuan County of Inner Mongolia as a test example. The results show that the fluctuation of spring wheat yield increased with the warming and drying climatic trend in Wuchuan County. The maximum yield decrease and its probability were 3.5 and 64.6%, respectively, for the temperature maximum increase 88.3%, and its risk was 2.2%. The maximum yield decrease and its probability were 14.1 and 56.1%, respectively, for the precipitation maximum decrease 35.2%, and its risk was 7.9%. For the comprehensive impacts of temperature and precipitation, the maximum yield decrease and its probability were 17.6 and 53.4%, respectively, and its risk increased to 9.4%. If we do not adopt appropriate adaptation strategies, the degree of loss from the negative impacts of multiclimatic factors and its probability of occurrence will both increase accordingly, and the risk will also grow obviously.

Simplified quantitative treatment of uncertainty and interindividual variability in health risk assessment

International Nuclear Information System (INIS)

Bogen, K.T.

1993-01-01

A distinction between uncertainty (or the extent of lack of knowledge) and interindividual variability (or the extent of person-to-person heterogeneity) regarding the values of input variates must be maintained if a quantitative characterization of uncertainty in population risk or in individual risk is sought. Here, some practical methods are presented that should facilitate implementation of the analytic framework for uncertainty and variability proposed by Bogen and Spear. (1,2) Two types of methodology are discussed: one that facilitates the distinction between uncertainty and variability per se, and another that may be used to simplify quantitative analysis of distributed inputs representing either uncertainty or variability. A simple and a complex form for modeled increased risk are presented and then used to illustrate methods facilitating the distinction between uncertainty and variability in reference to characterization of both population and individual risk. Finally, a simple form of discrete probability calculus is proposed as an easily implemented, practical altemative to Monte-Carlo based procedures to quantitative integration of uncertainty and variability in risk assessment

Fixing the cracks in the crystal ball: A maturity model for quantitative risk assessment

International Nuclear Information System (INIS)

Rae, Andrew; Alexander, Rob; McDermid, John

2014-01-01

Quantitative risk assessment (QRA) is widely practiced in system safety, but there is insufficient evidence that QRA in general is fit for purpose. Defenders of QRA draw a distinction between poor or misused QRA and correct, appropriately used QRA, but this distinction is only useful if we have robust ways to identify the flaws in an individual QRA. In this paper we present a comprehensive maturity model for QRA which covers all the potential flaws discussed in the risk assessment literature and in a collection of risk assessment peer reviews. We provide initial validation of the completeness and realism of the model. Our risk assessment maturity model provides a way to prioritise both process development within an organisation and empirical research within the QRA community. - Highlights: • Quantitative risk assessment (QRA) is widely practiced, but there is insufficient evidence that it is fit for purpose. • A given QRA may be good, or it may not – we need systematic ways to distinguish this. • We have created a maturity model for QRA which covers all the potential flaws discussed in the risk assessment literature. • We have provided initial validation of the completeness and realism of the model. • The maturity model can also be used to prioritise QRA research discipline-wide

Risk management and analysis: risk assessment (qualitative and quantitative)

OpenAIRE

Valentin Mazareanu

2007-01-01

We use to define risk as the possibility of suffering a loss. Starting this, risk management is defined as a business process whose purpose is to ensure that the organization is protected against risks and their effects. In order to prioritize, to develop a response plan and after that to monitor the identified risks we need to asses them. But at this point a question is born: should I choose a qualitative approach or a quantitative one? This paper will make a short overview over the risk eva...

Approaches to quantitative risk assessment with applications to PP

International Nuclear Information System (INIS)

Geiger, G.; Schaefer, A.

2002-01-01

Full text: Experience with accidents such as Goiania in Brazil and indications of a considerable number of orphan sources suggest that improved protection would be desirable for some types of radioactive material of wide-spread use such as radiation sources for civil purposes. Regarding large potential health and economic consequences (in particular, if terrorists attacks cannot be excluded), significant costs of preventive actions, and large uncertainties about both the likelihood of occurrence and the potential consequences of PP safety and security incidents, an optimum relationship between preventive and mitigative efforts is likely to be a key issue for successful risk management in this field. Thus, possible violations of physical protection combined with threats of misuse of nuclear materials, including terrorist attack, pose considerable challenges to global security from various perspectives. In view of these challenges, recent advance in applied risk and decision analysis suggests methodological and procedural improvements in quantitative risk assessment, the demarcation of acceptable risk, and risk management. Advance is based on a recently developed model of optimal risky choice suitable for assessing and comparing the cumulative probability distribution functions attached to safety and security risks. Besides quantification of risk (e. g., in economic terms), the standardization of various risk assessment models frequently used in operations research can be approached on this basis. The paper explores possible applications of these improved methods to the safety and security management of nuclear materials, cost efficiency of risk management measures, and the establishment international safety and security standards of PP. Examples will be presented that are based on selected scenarios of misuse involving typical radioactive sources. (author)

Quantitative risk assessment of continuous liquid spill fires based on spread and burning behaviours

DEFF Research Database (Denmark)

Zhao, Jinlong; Huang, Hong; Li, Yuntao

2017-01-01

Spill fires usually occur during the storage and transportation of hazardous materials, posing a threat to the people and environment in their immediate proximity. In this paper, a classical Quantitative Risk Assessment (QRA) method is used to assess the risk of spill fires. In this method......, the maximum spread area and the steady burning area are introduced as parameters to clearly assess the range of influence of the spill fire. In the calculations, a modified spread model that takes into consideration the burning rate variation is established to calculate the maximum spread area. Furthermore......, large-scale experiments of spill fires on water and a glass sheet were conducted to verify the accuracy and application of the model. The results show that the procedure we developed can be used to quantitatively calculate the risk associated with a continuous spill fire....

Genetic toxicology at the crossroads-from qualitative hazard evaluation to quantitative risk assessment.

Science.gov (United States)

White, Paul A; Johnson, George E

2016-05-01

Applied genetic toxicology is undergoing a transition from qualitative hazard identification to quantitative dose-response analysis and risk assessment. To facilitate this change, the Health and Environmental Sciences Institute (HESI) Genetic Toxicology Technical Committee (GTTC) sponsored a workshop held in Lancaster, UK on July 10-11, 2014. The event included invited speakers from several institutions and the contents was divided into three themes-1: Point-of-departure Metrics for Quantitative Dose-Response Analysis in Genetic Toxicology; 2: Measurement and Estimation of Exposures for Better Extrapolation to Humans and 3: The Use of Quantitative Approaches in Genetic Toxicology for human health risk assessment (HHRA). A host of pertinent issues were discussed relating to the use of in vitro and in vivo dose-response data, the development of methods for in vitro to in vivo extrapolation and approaches to use in vivo dose-response data to determine human exposure limits for regulatory evaluations and decision-making. This Special Issue, which was inspired by the workshop, contains a series of papers that collectively address topics related to the aforementioned themes. The Issue includes contributions that collectively evaluate, describe and discuss in silico, in vitro, in vivo and statistical approaches that are facilitating the shift from qualitative hazard evaluation to quantitative risk assessment. The use and application of the benchmark dose approach was a central theme in many of the workshop presentations and discussions, and the Special Issue includes several contributions that outline novel applications for the analysis and interpretation of genetic toxicity data. Although the contents of the Special Issue constitutes an important step towards the adoption of quantitative methods for regulatory assessment of genetic toxicity, formal acceptance of quantitative methods for HHRA and regulatory decision-making will require consensus regarding the

Affordable, automatic quantitative fall risk assessment based on clinical balance scales and Kinect data.

Science.gov (United States)

Colagiorgio, P; Romano, F; Sardi, F; Moraschini, M; Sozzi, A; Bejor, M; Ricevuti, G; Buizza, A; Ramat, S

2014-01-01

The problem of a correct fall risk assessment is becoming more and more critical with the ageing of the population. In spite of the available approaches allowing a quantitative analysis of the human movement control system's performance, the clinical assessment and diagnostic approach to fall risk assessment still relies mostly on non-quantitative exams, such as clinical scales. This work documents our current effort to develop a novel method to assess balance control abilities through a system implementing an automatic evaluation of exercises drawn from balance assessment scales. Our aim is to overcome the classical limits characterizing these scales i.e. limited granularity and inter-/intra-examiner reliability, to obtain objective scores and more detailed information allowing to predict fall risk. We used Microsoft Kinect to record subjects' movements while performing challenging exercises drawn from clinical balance scales. We then computed a set of parameters quantifying the execution of the exercises and fed them to a supervised classifier to perform a classification based on the clinical score. We obtained a good accuracy (~82%) and especially a high sensitivity (~83%).

Integrating expert opinion with modelling for quantitative multi-hazard risk assessment in the Eastern Italian Alps

Science.gov (United States)

Chen, Lixia; van Westen, Cees J.; Hussin, Haydar; Ciurean, Roxana L.; Turkington, Thea; Chavarro-Rincon, Diana; Shrestha, Dhruba P.

2016-11-01

Extreme rainfall events are the main triggering causes for hydro-meteorological hazards in mountainous areas, where development is often constrained by the limited space suitable for construction. In these areas, hazard and risk assessments are fundamental for risk mitigation, especially for preventive planning, risk communication and emergency preparedness. Multi-hazard risk assessment in mountainous areas at local and regional scales remain a major challenge because of lack of data related to past events and causal factors, and the interactions between different types of hazards. The lack of data leads to a high level of uncertainty in the application of quantitative methods for hazard and risk assessment. Therefore, a systematic approach is required to combine these quantitative methods with expert-based assumptions and decisions. In this study, a quantitative multi-hazard risk assessment was carried out in the Fella River valley, prone to debris flows and flood in the north-eastern Italian Alps. The main steps include data collection and development of inventory maps, definition of hazard scenarios, hazard assessment in terms of temporal and spatial probability calculation and intensity modelling, elements-at-risk mapping, estimation of asset values and the number of people, physical vulnerability assessment, the generation of risk curves and annual risk calculation. To compare the risk for each type of hazard, risk curves were generated for debris flows, river floods and flash floods. Uncertainties were expressed as minimum, average and maximum values of temporal and spatial probability, replacement costs of assets, population numbers, and physical vulnerability. These result in minimum, average and maximum risk curves. To validate this approach, a back analysis was conducted using the extreme hydro-meteorological event that occurred in August 2003 in the Fella River valley. The results show a good performance when compared to the historical damage reports.

Using integrated environmental modeling to automate a process-based Quantitative Microbial Risk Assessment

Science.gov (United States)

Integrated Environmental Modeling (IEM) organizes multidisciplinary knowledge that explains and predicts environmental-system response to stressors. A Quantitative Microbial Risk Assessment (QMRA) is an approach integrating a range of disparate data (fate/transport, exposure, an...

Study on quantitative risk assessment model of the third party damage for natural gas pipelines based on fuzzy comprehensive assessment

International Nuclear Information System (INIS)

Qiu, Zeyang; Liang, Wei; Lin, Yang; Zhang, Meng; Wang, Xue

2017-01-01

As an important part of national energy supply system, transmission pipelines for natural gas are possible to cause serious environmental pollution, life and property loss in case of accident. The third party damage is one of the most significant causes for natural gas pipeline system accidents, and it is very important to establish an effective quantitative risk assessment model of the third party damage for reducing the number of gas pipelines operation accidents. Against the third party damage accident has the characteristics such as diversity, complexity and uncertainty, this paper establishes a quantitative risk assessment model of the third party damage based on Analytic Hierarchy Process (AHP) and Fuzzy Comprehensive Evaluation (FCE). Firstly, risk sources of third party damage should be identified exactly, and the weight of factors could be determined via improved AHP, finally the importance of each factor is calculated by fuzzy comprehensive evaluation model. The results show that the quantitative risk assessment model is suitable for the third party damage of natural gas pipelines and improvement measures could be put forward to avoid accidents based on the importance of each factor. (paper)

Quantitative assessment of exposure and risk for three carcinogenics in long-standing pollution sites

International Nuclear Information System (INIS)

Wichmann, H.E.; Wuppertal Univ.; Ihme, W.; Mekel, O.C.L.; Wuppertal Univ.

1993-01-01

The project attempts a quantitative assessment of risks for three carcinogenics that are common in sites of long-standing pollution. Benzo(a)pyrene stands for the group of polycyclic aromatic hydrocarbons, cadmium for heavy metals, and benzene for volatile aromatic compounds. The report discusses the general fundamentals of exposure and risk assessment. The exposure model is described in detail and applied to the three test substances. (orig./MG) [de

A Quantitative Microbiological Risk Assessment for Salmonella in Pigs for the European Union

DEFF Research Database (Denmark)

Snary, Emma L.; Swart, Arno N.; Simons, Robin R. L.

2016-01-01

,000 and 1 in 10 million servings given consumption of one of the three product types considered (pork cuts, minced meat, and fermented ready‐to‐eat sausages). Further analyses of the farm‐to‐consumption QMRA suggest that the vast majority of human risk derives from infected pigs with a high concentration......A farm‐to‐consumption quantitative microbiological risk assessment (QMRA) for Salmonella in pigs in the European Union has been developed for the European Food Safety Authority. The primary aim of the QMRA was to assess the impact of hypothetical reductions of slaughter‐pig prevalence...

A methodology for the quantitative risk assessment of major accidents triggered by seismic events

International Nuclear Information System (INIS)

Antonioni, Giacomo; Spadoni, Gigliola; Cozzani, Valerio

2007-01-01

A procedure for the quantitative risk assessment of accidents triggered by seismic events in industrial facilities was developed. The starting point of the procedure was the use of available historical data to assess the expected frequencies and the severity of seismic events. Available equipment-dependant failure probability models (vulnerability or fragility curves) were used to assess the damage probability of equipment items due to a seismic event. An analytic procedure was subsequently developed to identify, evaluate the credibility and finally assess the expected consequences of all the possible scenarios that may follow the seismic events. The procedure was implemented in a GIS-based software tool in order to manage the high number of event sequences that are likely to be generated in large industrial facilities. The developed methodology requires a limited amount of additional data with respect to those used in a conventional QRA, and yields with a limited effort a preliminary quantitative assessment of the contribution of the scenarios triggered by earthquakes to the individual and societal risk indexes. The application of the methodology to several case-studies evidenced that the scenarios initiated by seismic events may have a relevant influence on industrial risk, both raising the overall expected frequency of single scenarios and causing specific severe scenarios simultaneously involving several plant units

Quantitative rock-fall hazard and risk assessment for Yosemite Valley, California

Science.gov (United States)

Stock, G. M.; Luco, N.; Collins, B. D.; Harp, E.; Reichenbach, P.; Frankel, K. L.

2011-12-01

Rock falls are a considerable hazard in Yosemite Valley, California with more than 835 rock falls and other slope movements documented since 1857. Thus, rock falls pose potentially significant risk to the nearly four million annual visitors to Yosemite National Park. Building on earlier hazard assessment work by the U.S. Geological Survey, we performed a quantitative rock-fall hazard and risk assessment for Yosemite Valley. This work was aided by several new data sets, including precise Geographic Information System (GIS) maps of rock-fall deposits, airborne and terrestrial LiDAR-based point cloud data and digital elevation models, and numerical ages of talus deposits. Using Global Position Systems (GPS), we mapped the positions of over 500 boulders on the valley floor and measured their distance relative to the mapped base of talus. Statistical analyses of these data yielded an initial hazard zone that is based on the 90th percentile distance of rock-fall boulders beyond the talus edge. This distance was subsequently scaled (either inward or outward from the 90th percentile line) based on rock-fall frequency information derived from a combination of cosmogenic beryllium-10 exposure dating of boulders beyond the edge of the talus, and computer model simulations of rock-fall runout. The scaled distances provide the basis for a new hazard zone on the floor of Yosemite Valley. Once this zone was delineated, we assembled visitor, employee, and resident use data for each structure within the hazard zone to quantitatively assess risk exposure. Our results identify areas within the new hazard zone that may warrant more detailed study, for example rock-fall susceptibility, which can be assessed through examination of high-resolution photographs, structural measurements on the cliffs, and empirical calculations derived from LiDAR point cloud data. This hazard and risk information is used to inform placement of existing and potential future infrastructure in Yosemite Valley.

Sugar concentration in nectar: a quantitative metric of crop attractiveness for refined pollinator risk assessments.

Science.gov (United States)

Knopper, Loren D; Dan, Tereza; Reisig, Dominic D; Johnson, Josephine D; Bowers, Lisa M

2016-10-01

Those involved with pollinator risk assessment know that agricultural crops vary in attractiveness to bees. Intuitively, this means that exposure to agricultural pesticides is likely greatest for attractive plants and lowest for unattractive plants. While crop attractiveness in the risk assessment process has been qualitatively remarked on by some authorities, absent is direction on how to refine the process with quantitative metrics of attractiveness. At a high level, attractiveness of crops to bees appears to depend on several key variables, including but not limited to: floral, olfactory, visual and tactile cues; seasonal availability; physical and behavioral characteristics of the bee; plant and nectar rewards. Notwithstanding the complexities and interactions among these variables, sugar content in nectar stands out as a suitable quantitative metric by which to refine pollinator risk assessments for attractiveness. Provided herein is a proposed way to use sugar nectar concentration to adjust the exposure parameter (with what is called a crop attractiveness factor) in the calculation of risk quotients in order to derive crop-specific tier I assessments. This Perspective is meant to invite discussion on incorporating such changes in the risk assessment process. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. © 2016 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Using Integrated Environmental Modeling to Automate a Process-Based Quantitative Microbial Risk Assessment (presentation)

Science.gov (United States)

Integrated Environmental Modeling (IEM) organizes multidisciplinary knowledge that explains and predicts environmental-system response to stressors. A Quantitative Microbial Risk Assessment (QMRA) is an approach integrating a range of disparate data (fate/transport, exposure, and...

A combined usage of stochastic and quantitative risk assessment methods in the worksites: Application on an electric power provider

International Nuclear Information System (INIS)

Marhavilas, P.K.; Koulouriotis, D.E.

2012-01-01

An individual method cannot build either a realistic forecasting model or a risk assessment process in the worksites, and future perspectives should focus on the combined forecasting/estimation approach. The main purpose of this paper is to gain insight into a risk prediction and estimation methodological framework, using the combination of three different methods, including the proportional quantitative-risk-assessment technique (PRAT), the time-series stochastic process (TSP), and the method of estimating the societal-risk (SRE) by F–N curves. In order to prove the usefulness of the combined usage of stochastic and quantitative risk assessment methods, an application on an electric power provider industry is presented to, using empirical data.

Risk Assessment and Integration Team (RAIT) Portfolio Risk Analysis Strategy

Science.gov (United States)

Edwards, Michelle

2010-01-01

Impact at management level: Qualitative assessment of risk criticality in conjunction with risk consequence, likelihood, and severity enable development of an "investment policy" towards managing a portfolio of risks. Impact at research level: Quantitative risk assessments enable researchers to develop risk mitigation strategies with meaningful risk reduction results. Quantitative assessment approach provides useful risk mitigation information.

Is there a place for quantitative risk assessment?

Energy Technology Data Exchange (ETDEWEB)

Hall, Eric J [Columbia University Medical Center, New York, NY (United States)

2009-06-01

The use of ionising radiations is so well established, especially in the practice of medicine, that it is impossible to imagine contemporary life without them. At the same time, ionising radiations are a known and proven human carcinogen. Exposure to radiation in some contexts elicits fear and alarm (nuclear power for example) while in other situations, until recently at least, it was accepted with alacrity (diagnostic x-rays for example). This non-uniform reaction to the potential hazards of radiation highlights the importance of quantitative risk estimates, which are necessary to help put things into perspective. Three areas will be discussed where quantitative risk estimates are needed and where uncertainties and limitations are a problem. First, the question of diagnostic x-rays. CT usage over the past quarter of a century has increased about 12 fold in the UK and more than 20 fold in the US. In both countries, more than 90% of the collective population dose from diagnostic x-rays comes from the few high dose procedures, such as interventional radiology, CT scans, lumbar spine x-rays and barium enemas. These all involve doses close to the lower limit at which there are credible epidemiological data for an excess cancer incidence. This is a critical question; what is the lowest dose at which there is good evidence of an elevated cancer incidence? Without low dose risk estimates the risk-benefit ratio of diagnostic procedures cannot be assessed. Second, the use of new techniques in radiation oncology. IMRT is widely used to obtain a more conformal dose distribution, particularly in children. It results in a larger total body dose, due to an increased number of monitor units and to the application of more radiation fields. The Linacs used today were not designed for IMRT and are based on leakage standards that were decided decades ago. It will be difficult and costly to reduce leakage from treatment machines, and a necessary first step is to refine the available

Is there a place for quantitative risk assessment?

International Nuclear Information System (INIS)

Hall, Eric J

2009-01-01

The use of ionising radiations is so well established, especially in the practice of medicine, that it is impossible to imagine contemporary life without them. At the same time, ionising radiations are a known and proven human carcinogen. Exposure to radiation in some contexts elicits fear and alarm (nuclear power for example) while in other situations, until recently at least, it was accepted with alacrity (diagnostic x-rays for example). This non-uniform reaction to the potential hazards of radiation highlights the importance of quantitative risk estimates, which are necessary to help put things into perspective. Three areas will be discussed where quantitative risk estimates are needed and where uncertainties and limitations are a problem. First, the question of diagnostic x-rays. CT usage over the past quarter of a century has increased about 12 fold in the UK and more than 20 fold in the US. In both countries, more than 90% of the collective population dose from diagnostic x-rays comes from the few high dose procedures, such as interventional radiology, CT scans, lumbar spine x-rays and barium enemas. These all involve doses close to the lower limit at which there are credible epidemiological data for an excess cancer incidence. This is a critical question; what is the lowest dose at which there is good evidence of an elevated cancer incidence? Without low dose risk estimates the risk-benefit ratio of diagnostic procedures cannot be assessed. Second, the use of new techniques in radiation oncology. IMRT is widely used to obtain a more conformal dose distribution, particularly in children. It results in a larger total body dose, due to an increased number of monitor units and to the application of more radiation fields. The Linacs used today were not designed for IMRT and are based on leakage standards that were decided decades ago. It will be difficult and costly to reduce leakage from treatment machines, and a necessary first step is to refine the available

Characterizing health risks associated with recreational swimming at Taiwanese beaches by using quantitative microbial risk assessment.

Science.gov (United States)

Jang, Cheng-Shin; Liang, Ching-Ping

2018-01-01

Taiwan is surrounded by oceans, and therefore numerous pleasure beaches attract millions of tourists annually to participate in recreational swimming activities. However, impaired water quality because of fecal pollution poses a potential threat to the tourists' health. This study probabilistically characterized the health risks associated with recreational swimming engendered by waterborne enterococci at 13 Taiwanese beaches by using quantitative microbial risk assessment. First, data on enterococci concentrations at coastal beaches monitored by the Taiwan Environmental Protection Administration were reproduced using nonparametric Monte Carlo simulation (MCS). The ingestion volumes of recreational swimming based on uniform and gamma distributions were subsequently determined using MCS. Finally, after the distribution combination of the two parameters, the beta-Poisson dose-response function was employed to quantitatively estimate health risks to recreational swimmers. Moreover, various levels of risk to recreational swimmers were classified and spatially mapped to explore feasible recreational and environmental management strategies at the beaches. The study results revealed that although the health risks associated with recreational swimming did not exceed an acceptable benchmark of 0.019 illnesses daily at all beaches, they approached to this benchmark at certain beaches. Beaches with relatively high risks are located in Northwestern Taiwan owing to the current movements.

A simplified method for quantitative assessment of the relative health and safety risk of environmental management activities

International Nuclear Information System (INIS)

Eide, S.A.; Smith, T.H.; Peatross, R.G.; Stepan, I.E.

1996-09-01

This report presents a simplified method to assess the health and safety risk of Environmental Management activities of the US Department of Energy (DOE). The method applies to all types of Environmental Management activities including waste management, environmental restoration, and decontamination and decommissioning. The method is particularly useful for planning or tradeoff studies involving multiple conceptual options because it combines rapid evaluation with a quantitative approach. The method is also potentially applicable to risk assessments of activities other than DOE Environmental Management activities if rapid quantitative results are desired

Modeling logistic performance in quantitative microbial risk assessment.

Science.gov (United States)

Rijgersberg, Hajo; Tromp, Seth; Jacxsens, Liesbeth; Uyttendaele, Mieke

2010-01-01

In quantitative microbial risk assessment (QMRA), food safety in the food chain is modeled and simulated. In general, prevalences, concentrations, and numbers of microorganisms in media are investigated in the different steps from farm to fork. The underlying rates and conditions (such as storage times, temperatures, gas conditions, and their distributions) are determined. However, the logistic chain with its queues (storages, shelves) and mechanisms for ordering products is usually not taken into account. As a consequence, storage times-mutually dependent in successive steps in the chain-cannot be described adequately. This may have a great impact on the tails of risk distributions. Because food safety risks are generally very small, it is crucial to model the tails of (underlying) distributions as accurately as possible. Logistic performance can be modeled by describing the underlying planning and scheduling mechanisms in discrete-event modeling. This is common practice in operations research, specifically in supply chain management. In this article, we present the application of discrete-event modeling in the context of a QMRA for Listeria monocytogenes in fresh-cut iceberg lettuce. We show the potential value of discrete-event modeling in QMRA by calculating logistic interventions (modifications in the logistic chain) and determining their significance with respect to food safety.

A suite of models to support the quantitative assessment of spread in pest risk analysis

NARCIS (Netherlands)

Robinet, C.; Kehlenbeck, H.; Werf, van der W.

2012-01-01

In the frame of the EU project PRATIQUE (KBBE-2007-212459 Enhancements of pest risk analysis techniques) a suite of models was developed to support the quantitative assessment of spread in pest risk analysis. This dataset contains the model codes (R language) for the four models in the suite. Three

A semi-quantitative model for risk appreciation and risk weighing

DEFF Research Database (Denmark)

Bos, Peter M.J.; Boon, Polly E.; van der Voet, Hilko

2009-01-01

Risk managers need detailed information on (1) the type of effect, (2) the size (severity) of the expected effect(s) and (3) the fraction of the population at risk to decide on well-balanced risk reduction measures. A previously developed integrated probabilistic risk assessment (IPRA) model...... provides quantitative information on these three parameters. A semi-quantitative tool is presented that combines information on these parameters into easy-readable charts that will facilitate risk evaluations of exposure situations and decisions on risk reduction measures. This tool is based on a concept...... detailed information on the estimated health impact in a given exposure situation. These graphs will facilitate the discussions on appropriate risk reduction measures to be taken....

Quantitative microbial risk assessment (QMRA) shows increased public health risk associated with exposure to river water under conditions of riverbed sediment resuspension

CSIR Research Space (South Africa)

Abia

2016-10-01

Full Text Available of The Total Environment, 556-557, pp 1143-1151 Quantitative microbial risk assessment (QMRA) shows increased public health risk associated with exposure to river water under conditions of riverbed sediment resuspension Akebe Luther King Abia a...

Local scale multiple quantitative risk assessment and uncertainty evaluation in a densely urbanised area (Brescia, Italy

Directory of Open Access Journals (Sweden)

S. Lari

2012-11-01

Full Text Available The study of the interactions between natural and anthropogenic risks is necessary for quantitative risk assessment in areas affected by active natural processes, high population density and strong economic activities.

We present a multiple quantitative risk assessment on a 420 km² high risk area (Brescia and surroundings, Lombardy, Northern Italy, for flood, seismic and industrial accident scenarios. Expected economic annual losses are quantified for each scenario and annual exceedance probability-loss curves are calculated. Uncertainty on the input variables is propagated by means of three different methodologies: Monte-Carlo-Simulation, First Order Second Moment, and point estimate.

Expected losses calculated by means of the three approaches show similar values for the whole study area, about 64 000 000 € for earthquakes, about 10 000 000 € for floods, and about 3000 € for industrial accidents. Locally, expected losses assume quite different values if calculated with the three different approaches, with differences up to 19%.

The uncertainties on the expected losses and their propagation, performed with the three methods, are compared and discussed in the paper. In some cases, uncertainty reaches significant values (up to almost 50% of the expected loss. This underlines the necessity of including uncertainty in quantitative risk assessment, especially when it is used as a support for territorial planning and decision making. The method is developed thinking at a possible application at a regional-national scale, on the basis of data available in Italy over the national territory.

An approach to quantitative assessment of relative proliferation risks from nuclear fuel cycles

International Nuclear Information System (INIS)

Silvennoinen, P.; Vira, J.

1981-01-01

Feasibility of quantitative assessments of the risk of nuclear weapons proliferation is discussed in this paper. The proliferation risk is defined as a combined utility of the different fuel cycle processes or materials for the proscribed acquisition of a nuclear weapon. Based on a set of selected weighted criteria, the process utilities are calculated employing utility functions or fuzzy expectation values. The methods are compared to each other. The scheme appears feasible in relative comparisons while certain leeway must still be retained for political judgement. (author)

Quantitative assessment of changes in landslide risk using a regional scale run-out model

Science.gov (United States)

Hussin, Haydar; Chen, Lixia; Ciurean, Roxana; van Westen, Cees; Reichenbach, Paola; Sterlacchini, Simone

2015-04-01

The risk of landslide hazard continuously changes in time and space and is rarely a static or constant phenomena in an affected area. However one of the main challenges of quantitatively assessing changes in landslide risk is the availability of multi-temporal data for the different components of risk. Furthermore, a truly "quantitative" landslide risk analysis requires the modeling of the landslide intensity (e.g. flow depth, velocities or impact pressures) affecting the elements at risk. Such a quantitative approach is often lacking in medium to regional scale studies in the scientific literature or is left out altogether. In this research we modelled the temporal and spatial changes of debris flow risk in a narrow alpine valley in the North Eastern Italian Alps. The debris flow inventory from 1996 to 2011 and multi-temporal digital elevation models (DEMs) were used to assess the susceptibility of debris flow triggering areas and to simulate debris flow run-out using the Flow-R regional scale model. In order to determine debris flow intensities, we used a linear relationship that was found between back calibrated physically based Flo-2D simulations (local scale models of five debris flows from 2003) and the probability values of the Flow-R software. This gave us the possibility to assign flow depth to a total of 10 separate classes on a regional scale. Debris flow vulnerability curves from the literature and one curve specifically for our case study area were used to determine the damage for different material and building types associated with the elements at risk. The building values were obtained from the Italian Revenue Agency (Agenzia delle Entrate) and were classified per cadastral zone according to the Real Estate Observatory data (Osservatorio del Mercato Immobiliare, Agenzia Entrate - OMI). The minimum and maximum market value for each building was obtained by multiplying the corresponding land-use value (€/msq) with building area and number of floors

Quantitative risk assessment of foods containing peanut advisory labeling.

Science.gov (United States)

Remington, Benjamin C; Baumert, Joseph L; Marx, David B; Taylor, Steve L

2013-12-01

Foods with advisory labeling (i.e. "may contain") continue to be prevalent and the warning may be increasingly ignored by allergic consumers. We sought to determine the residual levels of peanut in various packaged foods bearing advisory labeling, compare similar data from 2005 and 2009, and determine any potential risk for peanut-allergic consumers. Of food products bearing advisory statements regarding peanut or products that had peanut listed as a minor ingredient, 8.6% and 37.5% contained detectable levels of peanut (>2.5 ppm whole peanut), respectively. Peanut-allergic individuals should be advised to avoid such products regardless of the wording of the advisory statement. Peanut was detected at similar rates and levels in products tested in both 2005 and 2009. Advisory labeled nutrition bars contained the highest levels of peanut and an additional market survey of 399 products was conducted. Probabilistic risk assessment showed the risk of a reaction to peanut-allergic consumers from advisory labeled nutrition bars was significant but brand-dependent. Peanut advisory labeling may be overused on some nutrition bars but prudently used on others. The probabilistic approach could provide the food industry with a quantitative method to assist with determining when advisory labeling is most appropriate. Copyright © 2013 Elsevier Ltd. All rights reserved.

Quantitative risk analysis of urban flooding in lowland areas

NARCIS (Netherlands)

Ten Veldhuis, J.A.E.

2010-01-01

Urban flood risk analyses suffer from a lack of quantitative historical data on flooding incidents. Data collection takes place on an ad hoc basis and is usually restricted to severe events. The resulting data deficiency renders quantitative assessment of urban flood risks uncertain. The study

Exploration Health Risks: Probabilistic Risk Assessment

Science.gov (United States)

Rhatigan, Jennifer; Charles, John; Hayes, Judith; Wren, Kiley

2006-01-01

Maintenance of human health on long-duration exploration missions is a primary challenge to mission designers. Indeed, human health risks are currently the largest risk contributors to the risks of evacuation or loss of the crew on long-duration International Space Station missions. We describe a quantitative assessment of the relative probabilities of occurrence of the individual risks to human safety and efficiency during space flight to augment qualitative assessments used in this field to date. Quantitative probabilistic risk assessments will allow program managers to focus resources on those human health risks most likely to occur with undesirable consequences. Truly quantitative assessments are common, even expected, in the engineering and actuarial spheres, but that capability is just emerging in some arenas of life sciences research, such as identifying and minimize the hazards to astronauts during future space exploration missions. Our expectation is that these results can be used to inform NASA mission design trade studies in the near future with the objective of preventing the higher among the human health risks. We identify and discuss statistical techniques to provide this risk quantification based on relevant sets of astronaut biomedical data from short and long duration space flights as well as relevant analog populations. We outline critical assumptions made in the calculations and discuss the rationale for these. Our efforts to date have focussed on quantifying the probabilities of medical risks that are qualitatively perceived as relatively high risks of radiation sickness, cardiac dysrhythmias, medically significant renal stone formation due to increased calcium mobilization, decompression sickness as a result of EVA (extravehicular activity), and bone fracture due to loss of bone mineral density. We present these quantitative probabilities in order-of-magnitude comparison format so that relative risk can be gauged. We address the effects of

Quantitative Risk Assessment of Human Trichinellosis Caused by Consumption of Pork Meat Sausages in Argentina.

Science.gov (United States)

Sequeira, G J; Zbrun, M V; Soto, L P; Astesana, D M; Blajman, J E; Rosmini, M R; Frizzo, L S; Signorini, M L

2016-03-01

In Argentina, there are three known species of genus Trichinella; however, Trichinella spiralis is most commonly associated with domestic pigs and it is recognized as the main cause of human trichinellosis by the consumption of products made with raw or insufficiently cooked pork meat. In some areas of Argentina, this disease is endemic and it is thus necessary to develop a more effective programme of prevention and control. Here, we developed a quantitative risk assessment of human trichinellosis following pork meat sausage consumption, which may be used to identify the stages with greater impact on the probability of acquiring the disease. The quantitative model was designed to describe the conditions in which the meat is produced, processed, transported, stored, sold and consumed in Argentina. The model predicted a risk of human trichinellosis of 4.88 × 10(-6) and an estimated annual number of trichinellosis cases of 109. The risk of human trichinellosis was sensitive to the number of Trichinella larvae that effectively survived the storage period (r = 0.89), the average probability of infection (PPinf ) (r = 0.44) and the storage time (Storage) (r = 0.08). This model allowed assessing the impact of different factors influencing the risk of acquiring trichinellosis. The model may thus help to select possible strategies to reduce the risk in the chain of by-products of pork production. © 2015 Blackwell Verlag GmbH.

Quantitative assessment of the microbial risk of leafy greens from farm to consumption: preliminary framework, data, and risk estimates.

Science.gov (United States)

Danyluk, Michelle D; Schaffner, Donald W

2011-05-01

This project was undertaken to relate what is known about the behavior of Escherichia coli O157:H7 under laboratory conditions and integrate this information to what is known regarding the 2006 E. coli O157:H7 spinach outbreak in the context of a quantitative microbial risk assessment. The risk model explicitly assumes that all contamination arises from exposure in the field. Extracted data, models, and user inputs were entered into an Excel spreadsheet, and the modeling software @RISK was used to perform Monte Carlo simulations. The model predicts that cut leafy greens that are temperature abused will support the growth of E. coli O157:H7, and populations of the organism may increase by as much a 1 log CFU/day under optimal temperature conditions. When the risk model used a starting level of -1 log CFU/g, with 0.1% of incoming servings contaminated, the predicted numbers of cells per serving were within the range of best available estimates of pathogen levels during the outbreak. The model predicts that levels in the field of -1 log CFU/g and 0.1% prevalence could have resulted in an outbreak approximately the size of the 2006 E. coli O157:H7 outbreak. This quantitative microbial risk assessment model represents a preliminary framework that identifies available data and provides initial risk estimates for pathogenic E. coli in leafy greens. Data gaps include retail storage times, correlations between storage time and temperature, determining the importance of E. coli O157:H7 in leafy greens lag time models, and validation of the importance of cross-contamination during the washing process.

Quantitative Microbial Risk Assessment Tutorial Installation of Software for Watershed Modeling in Support of QMRA - Updated 2017

Science.gov (United States)

This tutorial provides instructions for accessing, retrieving, and downloading the following software to install on a host computer in support of Quantitative Microbial Risk Assessment (QMRA) modeling: • QMRA Installation • SDMProjectBuilder (which includes the Microbial ...

Quantitative Microbial Risk Assessment in Occupational Settings Applied to the Airborne Human Adenovirus Infection

Directory of Open Access Journals (Sweden)

Annalaura Carducci

2016-07-01

Full Text Available Quantitative Microbial Risk Assessment (QMRA methodology, which has already been applied to drinking water and food safety, may also be applied to risk assessment and management at the workplace. The present study developed a preliminary QMRA model to assess microbial risk that is associated with inhaling bioaerosols that are contaminated with human adenovirus (HAdV. This model has been applied to air contamination data from different occupational settings, including wastewater systems, solid waste landfills, and toilets in healthcare settings and offices, with different exposure times. Virological monitoring showed the presence of HAdVs in all the evaluated settings, thus confirming that HAdV is widespread, but with different average concentrations of the virus. The QMRA results, based on these concentrations, showed that toilets had the highest probability of viral infection, followed by wastewater treatment plants and municipal solid waste landfills. Our QMRA approach in occupational settings is novel, and certain caveats should be considered. Nonetheless, we believe it is worthy of further discussions and investigations.

Comparing models for quantitative risk assessment: an application to the European Registry of foreign body injuries in children.

Science.gov (United States)

Berchialla, Paola; Scarinzi, Cecilia; Snidero, Silvia; Gregori, Dario

2016-08-01

Risk Assessment is the systematic study of decisions subject to uncertain consequences. An increasing interest has been focused on modeling techniques like Bayesian Networks since their capability of (1) combining in the probabilistic framework different type of evidence including both expert judgments and objective data; (2) overturning previous beliefs in the light of the new information being received and (3) making predictions even with incomplete data. In this work, we proposed a comparison among Bayesian Networks and other classical Quantitative Risk Assessment techniques such as Neural Networks, Classification Trees, Random Forests and Logistic Regression models. Hybrid approaches, combining both Classification Trees and Bayesian Networks, were also considered. Among Bayesian Networks, a clear distinction between purely data-driven approach and combination of expert knowledge with objective data is made. The aim of this paper consists in evaluating among this models which best can be applied, in the framework of Quantitative Risk Assessment, to assess the safety of children who are exposed to the risk of inhalation/insertion/aspiration of consumer products. The issue of preventing injuries in children is of paramount importance, in particular where product design is involved: quantifying the risk associated to product characteristics can be of great usefulness in addressing the product safety design regulation. Data of the European Registry of Foreign Bodies Injuries formed the starting evidence for risk assessment. Results showed that Bayesian Networks appeared to have both the ease of interpretability and accuracy in making prediction, even if simpler models like logistic regression still performed well. © The Author(s) 2013.

Integrating a quantitative risk appraisal in a health impact assessment

DEFF Research Database (Denmark)

Adám, Balázs; Molnár, Agnes; Gulis, Gabriel

2013-01-01

BACKGROUND: Although the quantification of health outcomes in a health impact assessment (HIA) is scarce in practice, it is preferred by policymakers, as it assists various aspects of the decision-making process. This article provides an example of integrating a quantitative risk appraisal...... in an HIA performed for the recently adopted Hungarian anti-smoking policy which introduced a smoking ban in closed public places, workplaces and public transport vehicles, and is one of the most effective measures to decrease smoking-related ill health. METHODS: A comprehensive, prospective HIA...... to decrease the prevalence of active and passive smoking and result in a considerably positive effect on several diseases, among which lung cancer, chronic pulmonary diseases, coronary heart diseases and stroke have the greatest importance. The health gain calculated for the quantifiable health outcomes...

Quantitative Risk reduction estimation Tool For Control Systems, Suggested Approach and Research Needs

Energy Technology Data Exchange (ETDEWEB)

Miles McQueen; Wayne Boyer; Mark Flynn; Sam Alessi

2006-03-01

For the past year we have applied a variety of risk assessment technologies to evaluate the risk to critical infrastructure from cyber attacks on control systems. More recently, we identified the need for a stand alone control system risk reduction estimation tool to provide owners and operators of control systems with a more useable, reliable, and credible method for managing the risks from cyber attack. Risk is defined as the probability of a successful attack times the value of the resulting loss, typically measured in lives and dollars. Qualitative and ad hoc techniques for measuring risk do not provide sufficient support for cost benefit analyses associated with cyber security mitigation actions. To address the need for better quantitative risk reduction models we surveyed previous quantitative risk assessment research; evaluated currently available tools; developed new quantitative techniques [17] [18]; implemented a prototype analysis tool to demonstrate how such a tool might be used; used the prototype to test a variety of underlying risk calculational engines (e.g. attack tree, attack graph); and identified technical and research needs. We concluded that significant gaps still exist and difficult research problems remain for quantitatively assessing the risk to control system components and networks, but that a useable quantitative risk reduction estimation tool is not beyond reach.

Current developments in the assessment of petroleum hydrocarbon contaminated sites: Analysis, interpretation, and use of the TPH parameter for quantitative risk assessment

International Nuclear Information System (INIS)

Garcia-Surette, M.; Maynard, P.; Lamie, P.O.; Kaslick, C.

1995-01-01

In 1994, the Massachusetts Department of Environmental Protection (MDEP) estimated that petroleum-only cases comprised approximately one-half of the state's hazardous waste sites currently under investigation and/or remediation. Because of this significant percentage, it became clear that assessing petroleum sites more efficiently in terms of risk and cleanup alternatives was necessary. One of these key MDEP policies describes an alternative risk assessment approach enabling the quantitative characterization of total petroleum hydrocarbon (TPH)-related health risks. The approach relies on the use of an analytical technique by which the mass of petroleum hydrocarbons within specified carbon ranges is quantified. MDEP's TPH risk assessment approach was successfully employed at a residential site contaminated with No. 2 fuel oil. The combined use of MDEP's suggested analytical methods, alternative reference compounds and toxicity values, as well as chromatograms, standard dose equations, and an EPA-approved box model, facilitated the performance of a more realistic and cost-effective assessment of risk. Such assessment provided key management information to regulatory agencies, and project managers, as well as property owners concerned with potential property value loss

Databases applicable to quantitative hazard/risk assessment-Towards a predictive systems toxicology

International Nuclear Information System (INIS)

Waters, Michael; Jackson, Marcus

2008-01-01

The Workshop on The Power of Aggregated Toxicity Data addressed the requirement for distributed databases to support quantitative hazard and risk assessment. The authors have conceived and constructed with federal support several databases that have been used in hazard identification and risk assessment. The first of these databases, the EPA Gene-Tox Database was developed for the EPA Office of Toxic Substances by the Oak Ridge National Laboratory, and is currently hosted by the National Library of Medicine. This public resource is based on the collaborative evaluation, by government, academia, and industry, of short-term tests for the detection of mutagens and presumptive carcinogens. The two-phased evaluation process resulted in more than 50 peer-reviewed publications on test system performance and a qualitative database on thousands of chemicals. Subsequently, the graphic and quantitative EPA/IARC Genetic Activity Profile (GAP) Database was developed in collaboration with the International Agency for Research on Cancer (IARC). A chemical database driven by consideration of the lowest effective dose, GAP has served IARC for many years in support of hazard classification of potential human carcinogens. The Toxicological Activity Profile (TAP) prototype database was patterned after GAP and utilized acute, subchronic, and chronic data from the Office of Air Quality Planning and Standards. TAP demonstrated the flexibility of the GAP format for air toxics, water pollutants and other environmental agents. The GAP format was also applied to developmental toxicants and was modified to represent quantitative results from the rodent carcinogen bioassay. More recently, the authors have constructed: 1) the NIEHS Genetic Alterations in Cancer (GAC) Database which quantifies specific mutations found in cancers induced by environmental agents, and 2) the NIEHS Chemical Effects in Biological Systems (CEBS) Knowledgebase that integrates genomic and other biological data including

Stochastic evaluation of tsunami inundation and quantitative estimating tsunami risk

International Nuclear Information System (INIS)

Fukutani, Yo; Anawat, Suppasri; Abe, Yoshi; Imamura, Fumihiko

2014-01-01

We performed a stochastic evaluation of tsunami inundation by using results of stochastic tsunami hazard assessment at the Soma port in the Tohoku coastal area. Eleven fault zones along the Japan trench were selected as earthquake faults generating tsunamis. The results show that estimated inundation area of return period about 1200 years had good agreement with that in the 2011 Tohoku earthquake. In addition, we evaluated quantitatively tsunami risk for four types of building; a reinforced concrete, a steel, a brick and a wood at the Soma port by combining the results of inundation assessment and tsunami fragility assessment. The results of quantitative estimating risk would reflect properly vulnerability of the buildings, that the wood building has high risk and the reinforced concrete building has low risk. (author)

Using MFM methodology to generate and define major accident scenarios for quantitative risk assessment studies

DEFF Research Database (Denmark)

Hua, Xinsheng; Wu, Zongzhi; Lind, Morten

2017-01-01

to calculate likelihood of each MAS. Combining the likelihood of each scenario with a qualitative risk matrix, each major accident scenario is thereby ranked for consideration for detailed consequence analysis. The methodology is successfully highlighted using part of BMA-process for production of hydrogen......Generating and defining Major Accident Scenarios (MAS) are commonly agreed as the key step for quantitative risk assessment (QRA). The aim of the study is to explore the feasibility of using Multilevel Flow Modeling (MFM) methodology to formulating MAS. Traditionally this is usually done based...

Quantitative meta-analytic approaches for the analysis of animal toxicology and epidemiologic data in human health risk assessments

Science.gov (United States)

Often, human health risk assessments have relied on qualitative approaches for hazard identification to integrate evidence across multiple studies to conclude whether particular hazards exist. However, quantitative approaches for evidence integration, including the application o...

Quantitative risk analysis of a space shuttle subsystem

International Nuclear Information System (INIS)

Frank, M.V.

1989-01-01

This paper reports that in an attempt to investigate methods for risk management other than qualitative analysis techniques, NASA has funded pilot study quantitative risk analyses for space shuttle subsystems. The authors performed one such study of two shuttle subsystems with McDonnell Douglas Astronautics Company. The subsystems were the auxiliary power units (APU) on the orbiter, and the hydraulic power units on the solid rocket booster. The technology and results of the APU study are presented in this paper. Drawing from a rich in-flight database as well as from a wealth of tests and analyses, the study quantitatively assessed the risk of APU-initiated scenarios on the shuttle during all phases of a flight mission. Damage states of interest were loss of crew/vehicle, aborted mission, and launch scrub. A quantitative risk analysis approach to deciding on important items for risk management was contrasted with the current NASA failure mode and effects analysis/critical item list approach

Probabilistic risk assessment as an aid to risk management

International Nuclear Information System (INIS)

Garrick, B.J.

1982-01-01

Probabilistic risk assessments are providing important insights into nuclear power plant safety. Their value is two-fold: first as a means of quantifying nuclear plant risk including contributors to risk, and second as an aid to risk management. A risk assessment provides an analytical plant model that can be the basis for performing meaningful decision analyses for controlling safety. It is the aspect of quantitative risk management that makes probabilistic risk assessment an important technical discipline of the future

78 FR 9701 - Draft Joint Food and Drug Administration/Health Canada Quantitative Assessment of the Risk of...

Science.gov (United States)

2013-02-11

... on the sources of L. monocytogenes contamination, the effects of individual manufacturing and/or... DEPARTMENT OF HEALTH AND HUMAN SERVICES Food and Drug Administration [Docket No. FDA-2012-N-1182] Draft Joint Food and Drug Administration/Health Canada Quantitative Assessment of the Risk of...

Exploring probabilistic tools for the development of a platform for Quantitative Risk Assessment (QRA) of hydro-meteorological hazards in Europe

Science.gov (United States)

Zumpano, V.; Hussin, H. Y.; Breinl, K.

2012-04-01

Mass-movements and floods are hydro-meteorological hazards that can have catastrophic effects on communities living in mountainous areas prone to these disastrous events. Environmental, climate and socio-economic changes are expected to affect the tempo-spatial patterns of hydro-meteorological hazards and associated risks in Europe. These changes and their effects on the occurrence of future hazards need to be analyzed and modeled using probabilistic hazard and risk assessment methods in order to assist stakeholders in disaster management strategies and policy making. Quantitative Risk Assessment (QRA) using probabilistic methods can further calculate damage and losses to multi-hazards and determine the uncertainties related to all the probabilistic components of the hazard and the vulnerability of the elements at risk. Therefore, in order to develop an effective platform that can quantitatively calculate the risk of mass-movements and floods in several European test sites, an extensive inventory and analysis has been carried out of the available tools and software related to the probabilistic risk assessment of single and multi-hazards. The tools have been reviewed based on whether they are open source and freely available, their required input data, the availability and type of hazard and vulnerability modules, transparency of methods used, their validation and calibration techniques, the inclusion of uncertainties and their state of the art. The analysis also specially focused on the applicability of the tools to European study areas. The findings showed that assumptions and simplifications are made when assessing and quantifying the hazards. The interaction between multiple hazards, like cascading effects are not assessed in most tools and some consider the hazard and vulnerability as qualitative components, rather than quantitative ones. This analysis of hazard and risk assessment tools and software will give future developers and experts a better overview of

A probabilistic quantitative risk assessment model for the long-term work zone crashes.

Science.gov (United States)

Meng, Qiang; Weng, Jinxian; Qu, Xiaobo

2010-11-01

Work zones especially long-term work zones increase traffic conflicts and cause safety problems. Proper casualty risk assessment for a work zone is of importance for both traffic safety engineers and travelers. This paper develops a novel probabilistic quantitative risk assessment (QRA) model to evaluate the casualty risk combining frequency and consequence of all accident scenarios triggered by long-term work zone crashes. The casualty risk is measured by the individual risk and societal risk. The individual risk can be interpreted as the frequency of a driver/passenger being killed or injured, and the societal risk describes the relation between frequency and the number of casualties. The proposed probabilistic QRA model consists of the estimation of work zone crash frequency, an event tree and consequence estimation models. There are seven intermediate events--age (A), crash unit (CU), vehicle type (VT), alcohol (AL), light condition (LC), crash type (CT) and severity (S)--in the event tree. Since the estimated value of probability for some intermediate event may have large uncertainty, the uncertainty can thus be characterized by a random variable. The consequence estimation model takes into account the combination effects of speed and emergency medical service response time (ERT) on the consequence of work zone crash. Finally, a numerical example based on the Southeast Michigan work zone crash data is carried out. The numerical results show that there will be a 62% decrease of individual fatality risk and 44% reduction of individual injury risk if the mean travel speed is slowed down by 20%. In addition, there will be a 5% reduction of individual fatality risk and 0.05% reduction of individual injury risk if ERT is reduced by 20%. In other words, slowing down speed is more effective than reducing ERT in the casualty risk mitigation. 2010 Elsevier Ltd. All rights reserved.

Exploring the uncertainties in cancer risk assessment using the integrated probabilistic risk assessment (IPRA) approach.

Science.gov (United States)

Slob, Wout; Bakker, Martine I; Biesebeek, Jan Dirk Te; Bokkers, Bas G H

2014-08-01

Current methods for cancer risk assessment result in single values, without any quantitative information on the uncertainties in these values. Therefore, single risk values could easily be overinterpreted. In this study, we discuss a full probabilistic cancer risk assessment approach in which all the generally recognized uncertainties in both exposure and hazard assessment are quantitatively characterized and probabilistically evaluated, resulting in a confidence interval for the final risk estimate. The methodology is applied to three example chemicals (aflatoxin, N-nitrosodimethylamine, and methyleugenol). These examples illustrate that the uncertainty in a cancer risk estimate may be huge, making single value estimates of cancer risk meaningless. Further, a risk based on linear extrapolation tends to be lower than the upper 95% confidence limit of a probabilistic risk estimate, and in that sense it is not conservative. Our conceptual analysis showed that there are two possible basic approaches for cancer risk assessment, depending on the interpretation of the dose-incidence data measured in animals. However, it remains unclear which of the two interpretations is the more adequate one, adding an additional uncertainty to the already huge confidence intervals for cancer risk estimates. © 2014 Society for Risk Analysis.

Quantitative risk in radiation protection standards

International Nuclear Information System (INIS)

Bond, V.P.

1978-01-01

The bases for developing quantitative assessment of exposure risks in the human being, and the several problems that accompany the assessment and introduction of the risk of exposure to high and low LET radiation into radiation protection, will be evaluated. The extension of the pioneering radiation protection philosophies to the control of other hazardous agents that cannot be eliminated from the environment will be discussed, as will the serious misunderstandings and misuse of concepts and facts that have inevitably surrounded the application to one agent alone, of the protection philosophy that must in time be applied to a broad spectrum of potentially hazardous agents. (orig.) [de

HTGR accident and risk assessment

International Nuclear Information System (INIS)

Silady, F.A.; Everline, C.J.; Houghton, W.J.

1982-01-01

This paper is a synopsis of the high-temperature gas-cooled reactor probabilistic risk assessments (PRAs) performed by General Atomic Company. Principal topics presented include: HTGR safety assessments, peer interfaces, safety research, process gas explosions, quantitative safety goals, licensing applications of PRA, enhanced safety, investment risk assessments, and PRA design integration

Quantitative risk assessment of digitalized safety systems

Energy Technology Data Exchange (ETDEWEB)

Shin, Sung Min; Lee, Sang Hun; Kang, Hym Gook [KAIST, Daejeon (Korea, Republic of); Lee, Seung Jun [UNIST, Ulasn (Korea, Republic of)

2016-05-15

A report published by the U.S. National Research Council indicates that appropriate methods for assessing reliability are key to establishing the acceptability of digital instrumentation and control (I and C) systems in safety-critical plants such as NPPs. Since the release of this issue, the methodology for the probabilistic safety assessment (PSA) of digital I and C systems has been studied. However, there is still no widely accepted method. Kang and Sung found three critical factors for safety assessment of digital systems: detection coverage of fault-tolerant techniques, software reliability quantification, and network communication risk. In reality the various factors composing digitalized I and C systems are not independent of each other but rather closely connected. Thus, from a macro point of view, a method that can integrate risk factors with different characteristics needs to be considered together with the micro approaches to address the challenges facing each factor.

Understanding Pre-Quantitative Risk in Projects

Science.gov (United States)

Cooper, Lynne P.

2011-01-01

Standard approaches to risk management in projects depend on the ability of teams to identify risks and quantify the probabilities and consequences of these risks (e.g., the 5 x 5 risk matrix). However, long before quantification does - or even can - occur, and long after, teams make decisions based on their pre-quantitative understanding of risk. These decisions can have long-lasting impacts on the project. While significant research has looked at the process of how to quantify risk, our understanding of how teams conceive of and manage pre-quantitative risk is lacking. This paper introduces the concept of pre-quantitative risk and discusses the implications of addressing pre-quantitative risk in projects.

Skin sensitisation quantitative risk assessment (QRA) based on aggregate dermal exposure to methylisothiazolinone in personal care and household cleaning products.

NARCIS (Netherlands)

Ezendam, J; Bokkers, B G H; Bil, W; Delmaar, J E

2017-01-01

Contact allergy to preservatives is an important public health problem. Ideally, new substances should be evaluated for the risk on skin sensitization before market entry, for example by using a quantitative risk assessment (QRA) as developed for fragrances. As a proof-of-concept, this QRA was

Approaches to advancing quantitative human health risk assessment of environmental chemicals in the post-genomic era.

Science.gov (United States)

Chiu, Weihsueh A; Euling, Susan Y; Scott, Cheryl Siegel; Subramaniam, Ravi P

2013-09-15

The contribution of genomics and associated technologies to human health risk assessment for environmental chemicals has focused largely on elucidating mechanisms of toxicity, as discussed in other articles in this issue. However, there is interest in moving beyond hazard characterization to making more direct impacts on quantitative risk assessment (QRA)--i.e., the determination of toxicity values for setting exposure standards and cleanup values. We propose that the evolution of QRA of environmental chemicals in the post-genomic era will involve three, somewhat overlapping phases in which different types of approaches begin to mature. The initial focus (in Phase I) has been and continues to be on "augmentation" of weight of evidence--using genomic and related technologies qualitatively to increase the confidence in and scientific basis of the results of QRA. Efforts aimed towards "integration" of these data with traditional animal-based approaches, in particular quantitative predictors, or surrogates, for the in vivo toxicity data to which they have been anchored are just beginning to be explored now (in Phase II). In parallel, there is a recognized need for "expansion" of the use of established biomarkers of susceptibility or risk of human diseases and disorders for QRA, particularly for addressing the issues of cumulative assessment and population risk. Ultimately (in Phase III), substantial further advances could be realized by the development of novel molecular and pathway-based biomarkers and statistical and in silico models that build on anticipated progress in understanding the pathways of human diseases and disorders. Such efforts would facilitate a gradual "reorientation" of QRA towards approaches that more directly link environmental exposures to human outcomes. Published by Elsevier Inc.

Approaches to advancing quantitative human health risk assessment of environmental chemicals in the post-genomic era

Energy Technology Data Exchange (ETDEWEB)

Chiu, Weihsueh A., E-mail: chiu.weihsueh@epa.gov [National Center for Environmental Assessment, U.S. Environmental Protection Agency, Washington DC, 20460 (United States); Euling, Susan Y.; Scott, Cheryl Siegel; Subramaniam, Ravi P. [National Center for Environmental Assessment, U.S. Environmental Protection Agency, Washington DC, 20460 (United States)

2013-09-15

The contribution of genomics and associated technologies to human health risk assessment for environmental chemicals has focused largely on elucidating mechanisms of toxicity, as discussed in other articles in this issue. However, there is interest in moving beyond hazard characterization to making more direct impacts on quantitative risk assessment (QRA) — i.e., the determination of toxicity values for setting exposure standards and cleanup values. We propose that the evolution of QRA of environmental chemicals in the post-genomic era will involve three, somewhat overlapping phases in which different types of approaches begin to mature. The initial focus (in Phase I) has been and continues to be on “augmentation” of weight of evidence — using genomic and related technologies qualitatively to increase the confidence in and scientific basis of the results of QRA. Efforts aimed towards “integration” of these data with traditional animal-based approaches, in particular quantitative predictors, or surrogates, for the in vivo toxicity data to which they have been anchored are just beginning to be explored now (in Phase II). In parallel, there is a recognized need for “expansion” of the use of established biomarkers of susceptibility or risk of human diseases and disorders for QRA, particularly for addressing the issues of cumulative assessment and population risk. Ultimately (in Phase III), substantial further advances could be realized by the development of novel molecular and pathway-based biomarkers and statistical and in silico models that build on anticipated progress in understanding the pathways of human diseases and disorders. Such efforts would facilitate a gradual “reorientation” of QRA towards approaches that more directly link environmental exposures to human outcomes.

Approaches to advancing quantitative human health risk assessment of environmental chemicals in the post-genomic era

International Nuclear Information System (INIS)

Chiu, Weihsueh A.; Euling, Susan Y.; Scott, Cheryl Siegel; Subramaniam, Ravi P.

2013-01-01

The contribution of genomics and associated technologies to human health risk assessment for environmental chemicals has focused largely on elucidating mechanisms of toxicity, as discussed in other articles in this issue. However, there is interest in moving beyond hazard characterization to making more direct impacts on quantitative risk assessment (QRA) — i.e., the determination of toxicity values for setting exposure standards and cleanup values. We propose that the evolution of QRA of environmental chemicals in the post-genomic era will involve three, somewhat overlapping phases in which different types of approaches begin to mature. The initial focus (in Phase I) has been and continues to be on “augmentation” of weight of evidence — using genomic and related technologies qualitatively to increase the confidence in and scientific basis of the results of QRA. Efforts aimed towards “integration” of these data with traditional animal-based approaches, in particular quantitative predictors, or surrogates, for the in vivo toxicity data to which they have been anchored are just beginning to be explored now (in Phase II). In parallel, there is a recognized need for “expansion” of the use of established biomarkers of susceptibility or risk of human diseases and disorders for QRA, particularly for addressing the issues of cumulative assessment and population risk. Ultimately (in Phase III), substantial further advances could be realized by the development of novel molecular and pathway-based biomarkers and statistical and in silico models that build on anticipated progress in understanding the pathways of human diseases and disorders. Such efforts would facilitate a gradual “reorientation” of QRA towards approaches that more directly link environmental exposures to human outcomes

Skin sensitization quantitative risk assessment for occupational exposure of hairdressers to hair dye ingredients.

Science.gov (United States)

Goebel, Carsten; Diepgen, Thomas L; Blömeke, Brunhilde; Gaspari, Anthony A; Schnuch, Axel; Fuchs, Anne; Schlotmann, Kordula; Krasteva, Maya; Kimber, Ian

2018-06-01

Occupational exposure of hairdressers to hair dyes has been associated with the development of allergic contact dermatitis (ACD) involving the hands. p-Phenylenediamine (PPD) and toluene-2,5-diamine (PTD) have been implicated as important occupational contact allergens. To conduct a quantitative risk assessment for the induction of contact sensitization to hair dyes in hairdressers, available data from hand rinsing studies following typical occupational exposure conditions to PPD, PTD and resorcinol were assessed. By accounting for wet work, uneven exposure and inter-individual variability for professionals, daily hand exposure concentrations were derived. Secondly, daily hand exposure was compared with the sensitization induction potency of the individual hair dye defined as the No Expected Sensitization Induction Levels (NESIL). For PPD and PTD hairdresser hand exposure levels were 2.7 and 5.9 fold below the individual NESIL. In contrast, hand exposure to resorcinol was 50 fold below the NESIL. Correspondingly, the risk assessment for PPD and PTD indicates that contact sensitization may occur, when skin protection and skin care are not rigorously applied. We conclude that awareness of health risks associated with occupational exposure to hair dyes, and of the importance of adequate protective measures, should be emphasized more fully during hairdresser education and training. Copyright © 2018 Elsevier Inc. All rights reserved.

Quantitative microbial risk assessment of Cryptosporidium and Giardia in well water from a native community of Mexico.

Science.gov (United States)

Balderrama-Carmona, Ana Paola; Gortáres-Moroyoqui, Pablo; Álvarez-Valencia, Luis Humberto; Castro-Espinoza, Luciano; Balderas-Cortés, José de Jesús; Mondaca-Fernández, Iram; Chaidez-Quiroz, Cristóbal; Meza-Montenegro, María Mercedes

2015-01-01

Cryptosporidium and Giardia are gastrointestinal disease-causing organisms transmitted by the fecal-oral route, zoonotic and prevalent in all socioeconomic segments with greater emphasis in rural communities. The goal of this study was to assess the risk of cryptosporidiosis and giardiasis of Potam dwellers consuming drinking water from communal well water. To achieve the goal, quantitative microbial risk assessment (QMRA) was carried out as follows: (a) identification of Cryptosporidium oocysts and Giardia cysts in well water samples by information collection rule method, (b) assessment of exposure to healthy Potam residents, (c) dose-response modelling, and (d) risk characterization using an exponential model. All well water samples tested were positive for Cryptosporidium and Giardia. The QMRA results indicate a mean of annual risks of 99:100 (0.99) for cryptosporidiosis and 1:1 (1.0) for giardiasis. The outcome of the present study may drive decision-makers to establish an educational and treatment program to reduce the incidence of parasite-borne intestinal infection in the Potam community, and to conduct risk analysis programs in other similar rural communities in Mexico.

Assessment of the health impact of an environmental pollution and quantitative assessment of health risks; Estimation de l'impact sanitaire d'une pollution environnementale et evaluation quantitative des risques sanitaires

Energy Technology Data Exchange (ETDEWEB)

NONE

2005-09-15

The report made by a working group is written for experts in health risk assessment or for professionals involved in risk management. It proposes a methodological and conceptual framework which could build a unified approach to a quantitative assessment of health risks. In the first part, under the form of questions and answers, it defines the health impact, describes how to assess the excess of individual risk and the related hypothesis, how to pass from the excess of individual risk to the health impact, how to express the results of an health impact calculation, how to take the lack of knowledge into account at the different steps of this calculation, what is the significance of the result of such a calculation, and how useful an health impact assessment can be. The second part proposes a more detailed presentation of the scientific background for the health impact calculation with its indicators, its uncertainties, its practice in other countries, its relevance, and its fields of application. Then, after a comment of the dose-response relationship, it reports the scientific validity of the assessment of a number of cases.

IWGT report on quantitative approaches to genotoxicity risk assessment II. Use of point-of-departure (PoD) metrics in defining acceptable exposure limits and assessing human risk.

Science.gov (United States)

MacGregor, James T; Frötschl, Roland; White, Paul A; Crump, Kenny S; Eastmond, David A; Fukushima, Shoji; Guérard, Melanie; Hayashi, Makoto; Soeteman-Hernández, Lya G; Johnson, George E; Kasamatsu, Toshio; Levy, Dan D; Morita, Takeshi; Müller, Lutz; Schoeny, Rita; Schuler, Maik J; Thybaud, Véronique

2015-05-01

This is the second of two reports from the International Workshops on Genotoxicity Testing (IWGT) Working Group on Quantitative Approaches to Genetic Toxicology Risk Assessment (the QWG). The first report summarized the discussions and recommendations of the QWG related to the need for quantitative dose-response analysis of genetic toxicology data, the existence and appropriate evaluation of threshold responses, and methods to analyze exposure-response relationships and derive points of departure (PoDs) from which acceptable exposure levels could be determined. This report summarizes the QWG discussions and recommendations regarding appropriate approaches to evaluate exposure-related risks of genotoxic damage, including extrapolation below identified PoDs and across test systems and species. Recommendations include the selection of appropriate genetic endpoints and target tissues, uncertainty factors and extrapolation methods to be considered, the importance and use of information on mode of action, toxicokinetics, metabolism, and exposure biomarkers when using quantitative exposure-response data to determine acceptable exposure levels in human populations or to assess the risk associated with known or anticipated exposures. The empirical relationship between genetic damage (mutation and chromosomal aberration) and cancer in animal models was also examined. It was concluded that there is a general correlation between cancer induction and mutagenic and/or clastogenic damage for agents thought to act via a genotoxic mechanism, but that the correlation is limited due to an inadequate number of cases in which mutation and cancer can be compared at a sufficient number of doses in the same target tissues of the same species and strain exposed under directly comparable routes and experimental protocols. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Health risk assessment of exposure to ionizing radiation

International Nuclear Information System (INIS)

Ogata, Hiromitsu

2011-01-01

Risk assessment is an essential process for evaluating the human health effects of exposure to ionizing radiation and for determining acceptable levels of exposure. There are two major components of radiation risk assessment: a measure of exposure level and a measure of disease occurrence. For quantitative estimation of health risks, it is important to evaluate the association between exposure and disease occurrence using epidemiological or experimental data. In these approaches, statistical risk models are used particularly for estimating cancer risks related to exposure to low levels of radiation. This paper presents a summary of basic models and methods of risk assessment for studying exposure-risk relationships. Moreover, quantitative risk estimates are subject to several sources of uncertainty due to inherent limitations in risk assessment studies. This paper also discusses the limitations of radiation risk assessment. (author)

Quantitative microbial risk assessment to estimate the health risk from exposure to noroviruses in polluted surface water in South Africa.

Science.gov (United States)

Van Abel, Nicole; Mans, Janet; Taylor, Maureen B

2017-10-01

This study assessed the risks posed by noroviruses (NoVs) in surface water used for drinking, domestic, and recreational purposes in South Africa (SA), using a quantitative microbial risk assessment (QMRA) methodology that took a probabilistic approach coupling an exposure assessment with four dose-response models to account for uncertainty. Water samples from three rivers were found to be contaminated with NoV GI (80-1,900 gc/L) and GII (420-9,760 gc/L) leading to risk estimates that were lower for GI than GII. The volume of water consumed and the probabilities of infection were lower for domestic (2.91 × 10 -8 to 5.19 × 10 -1 ) than drinking water exposures (1.04 × 10 -5 to 7.24 × 10 -1 ). The annual probabilities of illness varied depending on the type of recreational water exposure with boating (3.91 × 10 -6 to 5.43 × 10 -1 ) and swimming (6.20 × 10 -6 to 6.42 × 10 -1 ) being slightly greater than playing next to/in the river (5.30 × 10 -7 to 5.48 × 10 -1 ). The QMRA was sensitive to the choice of dose-response model. The risk of NoV infection or illness from contaminated surface water is extremely high in SA, especially for lower socioeconomic individuals, but is similar to reported risks from limited international studies.

Use of quantitative uncertainty analysis for human health risk assessment

International Nuclear Information System (INIS)

Duncan, F.L.W.; Gordon, J.W.; Kelly, M.

1994-01-01

Current human health risk assessment method for environmental risks typically use point estimates of risk accompanied by qualitative discussions of uncertainty. Alternatively, Monte Carlo simulations may be used with distributions for input parameters to estimate the resulting risk distribution and descriptive risk percentiles. These two techniques are applied for the ingestion of 1,1=dichloroethene in ground water. The results indicate that Monte Carlo simulations provide significantly more information for risk assessment and risk management than do point estimates

HERMES docking/berthing system pilot study. Quantitative assessment

International Nuclear Information System (INIS)

Munoz Blasco, J.; Goicoechea Sanchez, F.J.

1993-01-01

This study falls within the framework of the incorporation of quantitative risk assessment to the activities planned for the ESA-HERMES project (ESA/ CNES). The main objective behind the study was the analysis and evaluation of the potential contribution of so-called probabilistic or quantitative safety analysis to the optimization of the safety development process for the systems carrying out the safety functions required by the new and complex HERMES Space Vehicle. For this purpose, a pilot study was considered a good start in quantitative safety assessments (QSA), as this approach has been frequently used in the past to establish a solid base in large-scale QSA application programs while avoiding considerable economic risks. It was finally decided to select the HERMES docking/berthing system with Man Tender Free Flyer as the case-study. This report describes the different steps followed in the study, along with the main insights obtained and the general conclusions drawn from the study results. (author)

Quantitative risk assessment using the capacity-demand analysis

International Nuclear Information System (INIS)

Morgenroth, M.; Donnelly, C.R.; Westermann, G.D.; Huang, J.H.S.; Lam, T.M.

1999-01-01

The hydroelectric industry's recognition of the importance of avoiding unexpected failure, or forced outages, led to the development of probabilistic, or risk-based, methods in order to attempt to quantify exposures. Traditionally, such analysis has been carried out by qualitative assessments, relying on experience and sound engineering judgment to determine the optimum time to maintain, repair or replace a part or system. Depending on the nature of the problem, however, and the level of experience of those included in the decision making process, it is difficult to find a balance between acting proactively and accepting some amount of risk. The development of a practical means for establishing the probability of failure of any part or system, based on the determination of the statistical distribution of engineering properties such as acting stresses, is discussed. The capacity-demand analysis methodology, coupled with probablistic, risk-based analysis, permits all the factors associated with a decision to rehabilitate or replace a part, including the risks associated with the timing of the decision, to be assessed in a transparent and defendable manner. The methodology does not eliminate judgment altogether, but does move it from the level of estimating the risk of failure to the lower level of estimating variability in material properties, uncertainty in loading, and the uncertainties inherent in any engineering analysis. The method was successfully used in 1998 to carry out a comprehensive, economic risk analysis for the entire water conveyance system of a 90 year old hydropower station. The analysis included a number of diverse parts ranging from rock slopes and aging steel and concrete conduits, and the method allowed a rational assessment of the risks associated with reach of these varied parts to be determined, permitting the essential remedial works to be prioritized. 14 refs., 4 figs

Distinguishing nanomaterial particles from background airborne particulate matter for quantitative exposure assessment

Science.gov (United States)

Ono-Ogasawara, Mariko; Serita, Fumio; Takaya, Mitsutoshi

2009-10-01

As the production of engineered nanomaterials quantitatively expands, the chance that workers involved in the manufacturing process will be exposed to nanoparticles also increases. A risk management system is needed for workplaces in the nanomaterial industry based on the precautionary principle. One of the problems in the risk management system is difficulty of exposure assessment. In this article, examples of exposure assessment in nanomaterial industries are reviewed with a focus on distinguishing engineered nanomaterial particles from background nanoparticles in workplace atmosphere. An approach by JNIOSH (Japan National Institute of Occupational Safety and Health) to quantitatively measure exposure to carbonaceous nanomaterials is also introduced. In addition to real-time measurements and qualitative analysis by electron microscopy, quantitative chemical analysis is necessary for quantitatively assessing exposure to nanomaterials. Chemical analysis is suitable for quantitative exposure measurement especially at facilities with high levels of background NPs.

Risk assessment for federal regulatory decisions on organisms produced through biotechnology

International Nuclear Information System (INIS)

Payne, John H.; Medley, Terry L.

1992-01-01

This article discusses: 1. Purposes and history of risk assessment: application to biotechnology; 2. Framework in the United States for decisions on organisms produced through biotechnology; 3. Choosing from among potential approaches to assessment: a). exposure assessment does not equate to risk assessment: what are the hazards?; b). Setting risk assessment priorities; c). 'Quantitative' environmental and 'quantitative' ecological risk assessments; d). Ecological risk assessments based on biological and ecological principles. 4. The bases for good regulatory decisions

Risk assessment for federal regulatory decisions on organisms produced through biotechnology

Energy Technology Data Exchange (ETDEWEB)

Payne, John H; Medley, Terry L [Biotechnology, Biologics and Environmental Protection Animal and Plant Health Inspection Service, U.S. Department of Agriculture, Hyattsville, MD (United States)

1992-07-01

This article discusses: 1. Purposes and history of risk assessment: application to biotechnology; 2. Framework in the United States for decisions on organisms produced through biotechnology; 3. Choosing from among potential approaches to assessment: a). exposure assessment does not equate to risk assessment: what are the hazards?; b). Setting risk assessment priorities; c). 'Quantitative' environmental and 'quantitative' ecological risk assessments; d). Ecological risk assessments based on biological and ecological principles. 4. The bases for good regulatory decisions.

Development of a Model for Quantitative Assessment of Risks and Identification of Threats in Anti-Crisis Management of a Machine-Building Enterprise

Directory of Open Access Journals (Sweden)

Kozyk Vasyl V.

2017-03-01

Full Text Available The aim of the article is to develop a model for quantitative assessment of risks in anti-crisis management of a machine-building enterprise. The quantitative assessment will allow to identify among the risks the threats that can be considered as catastrophic risks. To assess the integral risk of anti-crisis management of the enterprise, there used a process approach distinguishing the process of anti-crisis management activity and the process of implementation of the anti-crisis program. Within the framework of the process the types of activity are singled out, for each of them risks are identified with revealing their reasons. There built a fuzzy hierarchical model comprising the following elements: terminal nodes — indicators (factors of risks; non-terminal nodes — separate risks that are characteristic for the processes and risks of each process as a whole; root of the tree — the integral risk of anti-crisis management. The expediency of building a hierarchical fuzzy model, within which conclusions are formed for intermediate variables, is substantiated. Based on the own research and taking into account the opinion of experts, the parameters of the trapezoidal membership functions for assessing indicators and risks are determined. Fuzzy bases of knowledge about the correlation are formed using the Mamdani algorithm. The adequacy of the model is estimated on the basis of the learning sample. The built fuzzy model makes it possible to obtain risk assessment based on the set values of the indicators, thus providing an analysis of the sensitivity of risks to various factors. It is easily adjusted to other conditions and types of economic activity of the enterprise.

Physically based dynamic run-out modelling for quantitative debris flow risk assessment: a case study in Tresenda, northern Italy

Czech Academy of Sciences Publication Activity Database

Quan Luna, B.; Blahůt, Jan; Camera, C.; Van Westen, C.; Apuani, T.; Jetten, V.; Sterlacchini, S.

2014-01-01

Roč. 72, č. 3 (2014), s. 645-661 ISSN 1866-6280 Institutional support: RVO:67985891 Keywords : debris flow * FLO-2D * run-out * quantitative hazard and risk assessment * vulnerability * numerical modelling Subject RIV: DB - Geology ; Mineralogy Impact factor: 1.765, year: 2014

Uncertainty in ecological risk assessment: A statistician's view

International Nuclear Information System (INIS)

Smith, E.P.

1995-01-01

Uncertainty is a topic that has different meanings to researchers, modelers, managers and policy makers. The perspective of this presentation will be on the modeling view of uncertainty and its quantitative assessment. The goal is to provide some insight into how a statistician visualizes and addresses the issue of uncertainty in ecological risk assessment problems. In ecological risk assessment, uncertainty arises from many sources and is of different type depending on what is studies, where it is studied and how it is studied. Some major sources and their impact are described. A variety of quantitative approaches to modeling uncertainty are characterized and a general taxonomy given. Examples of risk assessments of lake acidification, power plant impact assessment and the setting of standards for chemicals will be used discuss approaches to quantitative assessment of uncertainty and some of the potential difficulties

Quantitative risk assessment of E. coli in street-vended cassava-based delicacies in the Philippines

Science.gov (United States)

Mesias, I. C. P.

2018-01-01

In the Philippines, rootcrop-based food products are gaining popularity in street food trade. However, a number of street-vended food products in the country are reported to be contaminated with E. coli posing possible risk among consumers. In this study, information on quantitative risk assessment of E. coli in street-vended cassava-based delicacies was generated. The assessment started with the prevalence and concentration of E. coli at post production in packages of the cassava-based delicacies. Combase growth predictor was used to trace the microbial population of E. coli in each step of the food chain. The @Risk software package, version 6 (Palisade USA) was used to run the simulations. Scenarios in the post-production to consumption pathway were simulated. The effect was then assessed in relation to exposure to the defined infective dose. In the worst case scenario, a minimum and most likely concentration of 6.3 and 7.8 log CFU of E. coli per serving respectively were observed. The simulation revealed that lowering the temperature in the chain considerably decreased the E. coli concentration prior to consumption and subsequently decreased the percentage of exposure to the infective dose. Exposure to infective dose however was increased with longer lag time from postproduction to consumption.

Quantitative microbiological risk assessment as a tool to obtain useful information for risk managers - specific application to Listeria monocytogenes and ready-to-eat meat products

NARCIS (Netherlands)

Mataragas, M.; Zwietering, M.H.; Skandamis, P.N.; Drosinos, E.H.

2010-01-01

The presence of Listeria monocytogenes in a sliced cooked, cured ham-like meat product was quantitatively assessed. Sliced cooked, cured meat products are considered as high risk products. These ready-to-eat, RTE, products (no special preparation, e.g. thermal treatment, before eating is required),

Risk assessment and risk management in managed aquifer recharge

CSIR Research Space (South Africa)

Page, D

2012-06-01

Full Text Available This chapter presents the methodologies used for risk assessment and risk management in MAR in Australia and the European Union, qualitative and quantitative approaches adopted within the RECLAIM Water project and case studies where the outcomes...

Risk prediction, safety analysis and quantitative probability methods - a caveat

International Nuclear Information System (INIS)

Critchley, O.H.

1976-01-01

Views are expressed on the use of quantitative techniques for the determination of value judgements in nuclear safety assessments, hazard evaluation, and risk prediction. Caution is urged when attempts are made to quantify value judgements in the field of nuclear safety. Criteria are given the meaningful application of reliability methods but doubts are expressed about their application to safety analysis, risk prediction and design guidances for experimental or prototype plant. Doubts are also expressed about some concomitant methods of population dose evaluation. The complexities of new designs of nuclear power plants make the problem of safety assessment more difficult but some possible approaches are suggested as alternatives to the quantitative techniques criticized. (U.K.)

The Pesticide Risk Beliefs Inventory: A Quantitative Instrument for the Assessment of Beliefs about Pesticide Risks

OpenAIRE

LePrevost, Catherine E.; Blanchard, Margaret R.; Cope, W. Gregory

2011-01-01

Recent media attention has focused on the risks that agricultural pesticides pose to the environment and human health; thus, these topics provide focal areas for scientists and science educators to enhance public understanding of basic toxicology concepts. This study details the development of a quantitative inventory to gauge pesticide risk beliefs. The goal of the inventory was to characterize misconceptions and knowledge gaps, as well as expert-like beliefs, concerning pesticide risk. This...

Quantitative risk assessment of the New York State operated West Valley Radioactive Waste Disposal Area.

Science.gov (United States)

Garrick, B John; Stetkar, John W; Bembia, Paul J

2010-08-01

This article is based on a quantitative risk assessment (QRA) that was performed on a radioactive waste disposal area within the Western New York Nuclear Service Center in western New York State. The QRA results were instrumental in the decision by the New York State Energy Research and Development Authority to support a strategy of in-place management of the disposal area for another decade. The QRA methodology adopted for this first of a kind application was a scenario-based approach in the framework of the triplet definition of risk (scenarios, likelihoods, consequences). The measure of risk is the frequency of occurrence of different levels of radiation dose to humans at prescribed locations. The risk from each scenario is determined by (1) the frequency of disruptive events or natural processes that cause a release of radioactive materials from the disposal area; (2) the physical form, quantity, and radionuclide content of the material that is released during each scenario; (3) distribution, dilution, and deposition of the released materials throughout the environment surrounding the disposal area; and (4) public exposure to the distributed material and the accumulated radiation dose from that exposure. The risks of the individual scenarios are assembled into a representation of the risk from the disposal area. In addition to quantifying the total risk to the public, the analysis ranks the importance of each contributing scenario, which facilitates taking corrective actions and implementing effective risk management. Perhaps most importantly, quantification of the uncertainties is an intrinsic part of the risk results. This approach to safety analysis has demonstrated many advantages of applying QRA principles to assessing the risk of facilities involving hazardous materials.

Probabilistic risk assessment, Volume I

International Nuclear Information System (INIS)

Anon.

1982-01-01

This book contains 158 papers presented at the International Topical Meeting on Probabilistic Risk Assessment held by the American Nuclear Society (ANS) and the European Nuclear Society (ENS) in Port Chester, New York in 1981. The meeting was second in a series of three. The main focus of the meeting was on the safety of light water reactors. The papers discuss safety goals and risk assessment. Quantitative safety goals, risk assessment in non-nuclear technologies, and operational experience and data base are also covered. Included is an address by Dr. Chauncey Starr

Safety analysis, risk assessment, and risk acceptance criteria

International Nuclear Information System (INIS)

Jamali, K.

1997-01-01

This paper discusses a number of topics that relate safety analysis as documented in the Department of Energy (DOE) safety analysis reports (SARs), probabilistic risk assessments (PRA) as characterized primarily in the context of the techniques that have assumed some level of formality in commercial nuclear power plant applications, and risk acceptance criteria as an outgrowth of PRA applications. DOE SARs of interest are those that are prepared for DOE facilities under DOE Order 5480.23 and the implementing guidance in DOE STD-3009-94. It must be noted that the primary area of application for DOE STD-3009 is existing DOE facilities and that certain modifications of the STD-3009 approach are necessary in SARs for new facilities. Moreover, it is the hazard analysis (HA) and accident analysis (AA) portions of these SARs that are relevant to the present discussions. Although PRAs can be qualitative in nature, PRA as used in this paper refers more generally to all quantitative risk assessments and their underlying methods. HA as used in this paper refers more generally to all qualitative risk assessments and their underlying methods that have been in use in hazardous facilities other than nuclear power plants. This discussion includes both quantitative and qualitative risk assessment methods. PRA has been used, improved, developed, and refined since the Reactor Safety Study (WASH-1400) was published in 1975 by the Nuclear Regulatory Commission (NRC). Much debate has ensued since WASH-1400 on exactly what the role of PRA should be in plant design, reactor licensing, 'ensuring' plant and process safety, and a large number of other decisions that must be made for potentially hazardous activities. Of particular interest in this area is whether the risks quantified using PRA should be compared with numerical risk acceptance criteria (RACs) to determine whether a facility is 'safe.' Use of RACs requires quantitative estimates of consequence frequency and magnitude

Quantitative risk assessment: an emerging tool for emerging foodborne pathogens.

OpenAIRE

Lammerding, A. M.; Paoli, G. M.

1997-01-01

New challenges to the safety of the food supply require new strategies for evaluating and managing food safety risks. Changes in pathogens, food preparation, distribution, and consumption, and population immunity have the potential to adversely affect human health. Risk assessment offers a framework for predicting the impact of changes and trends on the provision of safe food. Risk assessment models facilitate the evaluation of active or passive changes in how foods are produced, processed, d...

A quantitative risk assessment of multiple factors influencing HIV/AIDS transmission through unprotected sex among HIV-seropositive men.

Science.gov (United States)

Gerbi, Gemechu B; Habtemariam, Tsegaye; Tameru, Berhanu; Nganwa, David; Robnett, Vinaida

2012-01-01

The objective of this study is to conduct a quantitative risk assessment of multiple factors influencing HIV/AIDS transmission through unprotected sexual practices among HIV-seropositive men. A knowledgebase was developed by reviewing different published sources. The data were collected from different sources including Centers for Disease Control and Prevention, selected journals, and reports. The risk pathway scenario tree was developed based on a comprehensive review of published literature. The variables are organized into nine major parameter categories. Monte Carlo simulations for the quantitative risk assessment of HIV/AIDS transmission was executed with the software @Risk 4.0 (Palisade Corporation). Results show that the value for the likelihood of unprotected sex due to having less knowledge about HIV/AIDS and negative attitude toward condom use and safer sex ranged from 1.24 × 10(-5) to 8.47 × 10(-4) with the mean and standard deviation of 1.83 × 10(-4) and 8.63 × 10(-5), respectively. The likelihood of unprotected sex due to having greater anger-hostility, anxiety, less satisfied with aspects of life, and greater depressive symptoms ranged from 2.76 × 10(-9) to 5.34 × 10(-7) with the mean and standard deviation of 5.23 × 10(-8) and 3.58 × 10(-8), respectively. The findings suggest that HIV/AIDS research and intervention programs must be focused on behavior, and the broader setting within which individual risky behaviors occur.

A quantitative microbial risk assessment model for Listeria monocytogenes in RTE sandwiches

DEFF Research Database (Denmark)

Tirloni, E.; Stella, S.; de Knegt, Leonardo

2018-01-01

within each serving. Then, two dose-response models were alternatively applied: the first used a fixed r value for each of the three population groups, while the second considered a variable r value (lognormal distribution), taking into account the variability in strain virulence and different host...... subpopulations susceptibility. The stochastic model predicted zero cases for total population for both the substrates by using the fixed r approach, while 3 cases were expected when a higher variability (in virulence and susceptibility) was considered in the model; the number of cases increased to 45......A Quantitative Microbial Risk Assessment (QMRA) was performed to estimate the expected number of listeriosis cases due to the consumption, on the last day of shelf life, of 20 000 servings of multi-ingredient sandwiches produced by a medium scale food producer in Italy, by different population...

Quantitative falls risk estimation through multi-sensor assessment of standing balance.

Science.gov (United States)

Greene, Barry R; McGrath, Denise; Walsh, Lorcan; Doheny, Emer P; McKeown, David; Garattini, Chiara; Cunningham, Clodagh; Crosby, Lisa; Caulfield, Brian; Kenny, Rose A

2012-12-01

Falls are the most common cause of injury and hospitalization and one of the principal causes of death and disability in older adults worldwide. Measures of postural stability have been associated with the incidence of falls in older adults. The aim of this study was to develop a model that accurately classifies fallers and non-fallers using novel multi-sensor quantitative balance metrics that can be easily deployed into a home or clinic setting. We compared the classification accuracy of our model with an established method for falls risk assessment, the Berg balance scale. Data were acquired using two sensor modalities--a pressure sensitive platform sensor and a body-worn inertial sensor, mounted on the lower back--from 120 community dwelling older adults (65 with a history of falls, 55 without, mean age 73.7 ± 5.8 years, 63 female) while performing a number of standing balance tasks in a geriatric research clinic. Results obtained using a support vector machine yielded a mean classification accuracy of 71.52% (95% CI: 68.82-74.28) in classifying falls history, obtained using one model classifying all data points. Considering male and female participant data separately yielded classification accuracies of 72.80% (95% CI: 68.85-77.17) and 73.33% (95% CI: 69.88-76.81) respectively, leading to a mean classification accuracy of 73.07% in identifying participants with a history of falls. Results compare favourably to those obtained using the Berg balance scale (mean classification accuracy: 59.42% (95% CI: 56.96-61.88)). Results from the present study could lead to a robust method for assessing falls risk in both supervised and unsupervised environments.

Use of mechanistic simulations as a quantitative risk-ranking tool within the quality by design framework.

Science.gov (United States)

Stocker, Elena; Toschkoff, Gregor; Sacher, Stephan; Khinast, Johannes G

2014-11-20

The purpose of this study is to evaluate the use of computer simulations for generating quantitative knowledge as a basis for risk ranking and mechanistic process understanding, as required by ICH Q9 on quality risk management systems. In this specific publication, the main focus is the demonstration of a risk assessment workflow, including a computer simulation for the generation of mechanistic understanding of active tablet coating in a pan coater. Process parameter screening studies are statistically planned under consideration of impacts on a potentially critical quality attribute, i.e., coating mass uniformity. Based on computer simulation data the process failure mode and effects analysis of the risk factors is performed. This results in a quantitative criticality assessment of process parameters and the risk priority evaluation of failure modes. The factor for a quantitative reassessment of the criticality and risk priority is the coefficient of variation, which represents the coating mass uniformity. The major conclusion drawn from this work is a successful demonstration of the integration of computer simulation in the risk management workflow leading to an objective and quantitative risk assessment. Copyright © 2014. Published by Elsevier B.V.

EFSA Panel on Biological Hazards; Scientific Opinion on a Quantitative Microbiological Risk Assessment of Salmonella in slaughter and breeder pigs

DEFF Research Database (Denmark)

Hald, Tine

This Quantitative Microbiological Risk Assessment (QMRA) represents a major step forward in terms of modelling Salmonella in pigs from farm to consumption as it takes into account the variability between and within EU Member States (MSs). Around 10-20% of human Salmonella infections in EU may...

Quantitative risk assessment for environmental and occupational health. The practical solution

International Nuclear Information System (INIS)

Hallenbeck, W.H.; Cunningham, K.M.

1986-01-01

These following topics are covered in this book: concepts, methods, and limitations; exposure characterization; qualitative evaluation of human and animal studies; quantitative evaluation of human and animal studies; risk analysis; acceptable concentrations; environmental and occupational exposure to a hypothetical toxicant; and environmental exposure to a natural toxicant radon-222 and its daughters

An educationally inspired illustration of two-dimensional Quantitative Microbiological Risk Assessment (QMRA) and sensitivity analysis.

Science.gov (United States)

Vásquez, G A; Busschaert, P; Haberbeck, L U; Uyttendaele, M; Geeraerd, A H

2014-11-03

Quantitative Microbiological Risk Assessment (QMRA) is a structured methodology used to assess the risk involved by ingestion of a pathogen. It applies mathematical models combined with an accurate exploitation of data sets, represented by distributions and - in the case of two-dimensional Monte Carlo simulations - their hyperparameters. This research aims to highlight background information, assumptions and truncations of a two-dimensional QMRA and advanced sensitivity analysis. We believe that such a detailed listing is not always clearly presented in actual risk assessment studies, while it is essential to ensure reliable and realistic simulations and interpretations. As a case-study, we are considering the occurrence of listeriosis in smoked fish products in Belgium during the period 2008-2009, using two-dimensional Monte Carlo and two sensitivity analysis methods (Spearman correlation and Sobol sensitivity indices) to estimate the most relevant factors of the final risk estimate. A risk estimate of 0.018% per consumption of contaminated smoked fish by an immunocompromised person was obtained. The final estimate of listeriosis cases (23) is within the actual reported result obtained for the same period and for the same population. Variability on the final risk estimate is determined by the variability regarding (i) consumer refrigerator temperatures, (ii) the reference growth rate of L. monocytogenes, (iii) the minimum growth temperature of L. monocytogenes and (iv) consumer portion size. Variability regarding the initial contamination level of L. monocytogenes tends to appear as a determinant of risk variability only when the minimum growth temperature is not included in the sensitivity analysis; when it is included the impact regarding the variability on the initial contamination level of L. monocytogenes is disappearing. Uncertainty determinants of the final risk indicated the need of gathering more information on the reference growth rate and the minimum

Quantitative Microbial Risk Assessment for Escherichia coli O157:H7 in Fresh-Cut Lettuce.

Science.gov (United States)

Pang, Hao; Lambertini, Elisabetta; Buchanan, Robert L; Schaffner, Donald W; Pradhan, Abani K

2017-02-01

Leafy green vegetables, including lettuce, are recognized as potential vehicles for foodborne pathogens such as Escherichia coli O157:H7. Fresh-cut lettuce is potentially at high risk of causing foodborne illnesses, as it is generally consumed without cooking. Quantitative microbial risk assessments (QMRAs) are gaining more attention as an effective tool to assess and control potential risks associated with foodborne pathogens. This study developed a QMRA model for E. coli O157:H7 in fresh-cut lettuce and evaluated the effects of different potential intervention strategies on the reduction of public health risks. The fresh-cut lettuce production and supply chain was modeled from field production, with both irrigation water and soil as initial contamination sources, to consumption at home. The baseline model (with no interventions) predicted a mean probability of 1 illness per 10 million servings and a mean of 2,160 illness cases per year in the United States. All intervention strategies evaluated (chlorine, ultrasound and organic acid, irradiation, bacteriophage, and consumer washing) significantly reduced the estimated mean number of illness cases when compared with the baseline model prediction (from 11.4- to 17.9-fold reduction). Sensitivity analyses indicated that retail and home storage temperature were the most important factors affecting the predicted number of illness cases. The developed QMRA model provided a framework for estimating risk associated with consumption of E. coli O157:H7-contaminated fresh-cut lettuce and can guide the evaluation and development of intervention strategies aimed at reducing such risk.

Prediction of Maintenance Period of Equipment Through Risk Assessment of Thermal Power Plants

Energy Technology Data Exchange (ETDEWEB)

Song, Gee Wook; Kim, Bum Shin; Choi, Woo Song; Park, Myung Soo [KEPCO Research Institute, Daejeon (Korea, Republic of)

2013-10-15

Risk-based inspection (RBI) is a well-known method that is used to optimize inspection activities based on risk analysis in order to identify the high-risk components of major facilities such as power plants. RBI, when implemented and maintained properly, improves plant reliability and safety while reducing unplanned outages and repair costs. Risk is given by the product of the probability of failure (Pof) and the consequence of failure (COF). A semi-quantitative method is generally used for risk assessment. Semi-quantitative risk assessment complements the low accuracy of qualitative risk assessment and the high expense and long calculation time of quantitative risk assessment. The first step of RB I is to identify important failure modes and causes in the equipment. Once these are defined, the Pof and COF can be assessed for each failure. During Pof and COF assessment, an effective inspection method and range can be easily found. In this paper, the calculation of the Pof is improved for accurate risk assessment. A modified semi-quantitative risk assessment was carried out for boiler facilities of thermal power plants, and the next maintenance schedules for the equipment were decided.

Prediction of Maintenance Period of Equipment Through Risk Assessment of Thermal Power Plants

International Nuclear Information System (INIS)

Song, Gee Wook; Kim, Bum Shin; Choi, Woo Song; Park, Myung Soo

2013-01-01

Risk-based inspection (RBI) is a well-known method that is used to optimize inspection activities based on risk analysis in order to identify the high-risk components of major facilities such as power plants. RBI, when implemented and maintained properly, improves plant reliability and safety while reducing unplanned outages and repair costs. Risk is given by the product of the probability of failure (Pof) and the consequence of failure (COF). A semi-quantitative method is generally used for risk assessment. Semi-quantitative risk assessment complements the low accuracy of qualitative risk assessment and the high expense and long calculation time of quantitative risk assessment. The first step of RB I is to identify important failure modes and causes in the equipment. Once these are defined, the Pof and COF can be assessed for each failure. During Pof and COF assessment, an effective inspection method and range can be easily found. In this paper, the calculation of the Pof is improved for accurate risk assessment. A modified semi-quantitative risk assessment was carried out for boiler facilities of thermal power plants, and the next maintenance schedules for the equipment were decided

Quantitative coronary plaque analysis predicts high-risk plaque morphology on coronary computed tomography angiography: results from the ROMICAT II trial.

Science.gov (United States)

Liu, Ting; Maurovich-Horvat, Pál; Mayrhofer, Thomas; Puchner, Stefan B; Lu, Michael T; Ghemigian, Khristine; Kitslaar, Pieter H; Broersen, Alexander; Pursnani, Amit; Hoffmann, Udo; Ferencik, Maros

2018-02-01

Semi-automated software can provide quantitative assessment of atherosclerotic plaques on coronary CT angiography (CTA). The relationship between established qualitative high-risk plaque features and quantitative plaque measurements has not been studied. We analyzed the association between quantitative plaque measurements and qualitative high-risk plaque features on coronary CTA. We included 260 patients with plaque who underwent coronary CTA in the Rule Out Myocardial Infarction/Ischemia Using Computer Assisted Tomography (ROMICAT) II trial. Quantitative plaque assessment and qualitative plaque characterization were performed on a per coronary segment basis. Quantitative coronary plaque measurements included plaque volume, plaque burden, remodeling index, and diameter stenosis. In qualitative analysis, high-risk plaque was present if positive remodeling, low CT attenuation plaque, napkin-ring sign or spotty calcium were detected. Univariable and multivariable logistic regression analyses were performed to assess the association between quantitative and qualitative high-risk plaque assessment. Among 888 segments with coronary plaque, high-risk plaque was present in 391 (44.0%) segments by qualitative analysis. In quantitative analysis, segments with high-risk plaque had higher total plaque volume, low CT attenuation plaque volume, plaque burden and remodeling index. Quantitatively assessed low CT attenuation plaque volume (odds ratio 1.12 per 1 mm 3 , 95% CI 1.04-1.21), positive remodeling (odds ratio 1.25 per 0.1, 95% CI 1.10-1.41) and plaque burden (odds ratio 1.53 per 0.1, 95% CI 1.08-2.16) were associated with high-risk plaque. Quantitative coronary plaque characteristics (low CT attenuation plaque volume, positive remodeling and plaque burden) measured by semi-automated software correlated with qualitative assessment of high-risk plaque features.

Coupling mode-destination accessibility with seismic risk assessment to identify at-risk communities

International Nuclear Information System (INIS)

Miller, Mahalia; Baker, Jack W.

2016-01-01

In this paper, we develop a framework for coupling mode-destination accessibility with quantitative seismic risk assessment to identify communities at high risk for travel disruptions after an earthquake. Mode-destination accessibility measures the ability of people to reach destinations they desire. We use a probabilistic seismic risk assessment procedure, including a stochastic set of earthquake events, ground-motion intensity maps, damage maps, and realizations of traffic and accessibility impacts. For a case study of the San Francisco Bay Area, we couple our seismic risk framework with a practical activity-based traffic model. As a result, we quantify accessibility risk probabilistically by community and household type. We find that accessibility varies more strongly as a function of travelers' geographic location than as a function of their income class, and we identify particularly at-risk communities. We also observe that communities more conducive to local trips by foot or bike are predicted to be less impacted by losses in accessibility. This work shows the potential to link quantitative risk assessment methodologies with high-resolution travel models used by transportation planners. Quantitative risk metrics of this type should have great utility for planners working to reduce risk to a region's infrastructure systems. - Highlights: • We couple mode-destination accessibility with probabilistic seismic risk assessment. • Results identify communities at high risk for post-earthquake travel disruptions. • Accessibility varies more as a function of home location than by income. • Our model predicts reduced accessibility risk for more walking-friendly communities.

Genetic toxicology and cancer risk assessment

National Research Council Canada - National Science Library

Choy, Wai Nang

2001-01-01

... their risks to humans are obvious goals for the protection of public health. When exposure is unavoidable, an accurate estimation of human risk as a result of exposure is essential for making regulatory decisions. Quantitative cancer risk assessment is an intricate process that utilizes knowledge from many different scien...

Development of a Quantitative Framework for Regulatory Risk Assessments: Probabilistic Approaches

International Nuclear Information System (INIS)

Wilmot, R.D.

2003-11-01

The Swedish regulators have been active in the field of performance assessment for many years and have developed sophisticated approaches to the development of scenarios and other aspects of assessments. These assessments have generally used dose as the assessment end-point and have been based on deterministic calculations. Recently introduced Swedish regulations have introduced a risk criterion for radioactive waste disposal: the annual risk of harmful effects after closure of a disposal facility should not exceed 10 -6 for a representative individual in the group exposed to the greatest risk. A recent review of the overall structure of risk assessments in safety cases concluded that there are a number of decisions and assumptions in the development of a risk assessment methodology that could potentially affect the calculated results. Regulatory understanding of these issues, potentially supported by independent calculations, is important in preparing for review of a proponent's risk assessment. One approach to evaluating risk in performance assessments is to use the concept of probability to express uncertainties, and to propagate these probabilities through the analysis. This report describes the various approaches available for undertaking such probabilistic analyses, both as a means of accounting for uncertainty in the determination of risk and more generally as a means of sensitivity and uncertainty analysis. The report discusses the overall nature of probabilistic analyses and how they are applied to both the calculation of risk and sensitivity analyses. Several approaches are available, including differential analysis, response surface methods and simulation. Simulation is the approach most commonly used, both in assessments for radioactive waste disposal and in other subject areas, and the report describes the key stages of this approach in detail. Decisions relating to the development of input PDFs, sampling methods (including approaches to the treatment

Fire Risk Assessment in Germany

International Nuclear Information System (INIS)

Berg, H. P.

2000-01-01

Quantitative fire risk assessment can serve as an additional tool to assess the safety level of a nuclear power plant (NPP) and to set priorities for fire protection improvement measures. The recommended approach to be applied within periodic safety reviews of NPPs in Germany starts with a screening process providing critical fire zones in which a fully developed fire has the potential to both cause an initiating event and impair the function of at least one component or system critical to safety. The second step is to perform a quantitative analysis using a standard event tree has been developed with elements for fire initiation, ventilation of the room, fire detection, fire suppression, and fire propagation. In a final step, the fire induced frequency of initiating events, the main contributors and the calculated hazard state frequency for the fire event are determined. Results of the first quantitative fire risk studies performed in Germany are reported. (author)

Use of static Quantitative Microbial Risk Assessment to determine pathogen risks in an unconfined carbonate aquifer used for Managed Aquifer Recharge.

Science.gov (United States)

Toze, Simon; Bekele, Elise; Page, Declan; Sidhu, Jatinder; Shackleton, Mark

2010-02-01

Managed Aquifer Recharge (MAR) is becoming a mechanism used for recycling treated wastewater and captured urban stormwater and is being used as a treatment barrier to remove contaminants such as pathogens from the recharged water. There is still a need, however, to demonstrate the effectiveness of MAR to reduce any residual risk of pathogens in the recovered water. A MAR research site recharging secondary treated wastewater in an unconfined carbonate aquifer was used in conjunction with a static Quantitative Microbial Risk Assessment (QMRA) to assess the microbial pathogen risk in the recovered water following infiltration and aquifer passage. The research involved undertaking a detailed hydrogeological assessment of the aquifer at the MAR site and determining the decay rates of reference pathogens from an in-situ decay study. These variables along with literature data were then used in the static QMRA which demonstrated that the recovered water at this site did not meet the Australian Guidelines for recycled water when used for differing private green space irrigation scenarios. The results also confirmed the importance of obtaining local hydrogeological data as local heterogeneity can influence of residence time in the aquifer which, in turn, influences the outcomes. The research demonstrated that a static QMRA can be used to determine the residual risk from pathogens in recovered water and showed that it can be a valuable tool in the preliminary design and operation of MAR systems and the incorporation of complementary engineered treatment processes to ensure that there is acceptable health risk from the recovered water. Crown Copyright 2009. Published by Elsevier Ltd. All rights reserved.

Risk assessment for transport operations

International Nuclear Information System (INIS)

Appleton, P.R.; Miles, J.C.

1990-01-01

The world-wide safety of the transport of radioactive material is based on the IAEA Transport Regulations. Risk assessment can provide quantitative data to help in the demonstration, understanding and improvement of the effectiveness of the Regulations in assuring safety. In this Paper the methodology, data and computer codes necessary and available for transport risk assessment are reviewed. Notable examples of assessments carried out over the past 15 years are briefly described along with current research, and the benefits and limitations of the techniques are discussed. (author)

Quantitative microbiological risk assessment in food industry: Theory and practical application.

Science.gov (United States)

Membré, Jeanne-Marie; Boué, Géraldine

2018-04-01

The objective of this article is to bring scientific background as well as practical hints and tips to guide risk assessors and modelers who want to develop a quantitative Microbiological Risk Assessment (MRA) in an industrial context. MRA aims at determining the public health risk associated with biological hazards in a food. Its implementation in industry enables to compare the efficiency of different risk reduction measures, and more precisely different operational settings, by predicting their effect on the final model output. The first stage in MRA is to clearly define the purpose and scope with stakeholders, risk assessors and modelers. Then, a probabilistic model is developed; this includes schematically three important phases. Firstly, the model structure has to be defined, i.e. the connections between different operational processing steps. An important step in food industry is the thermal processing leading to microbial inactivation. Growth of heat-treated surviving microorganisms and/or post-process contamination during storage phase is also important to take into account. Secondly, mathematical equations are determined to estimate the change of microbial load after each processing step. This phase includes the construction of model inputs by collecting data or eliciting experts. Finally, the model outputs are obtained by simulation procedures, they have to be interpreted and communicated to targeted stakeholders. In this latter phase, tools such as what-if scenarios provide an essential added value. These different MRA phases are illustrated through two examples covering important issues in industry. The first one covers process optimization in a food safety context, the second one covers shelf-life determination in a food quality context. Although both contexts required the same methodology, they do not have the same endpoint: up to the human health in the foie gras case-study illustrating here a safety application, up to the food portion in the

Quantitative falls risk estimation through multi-sensor assessment of standing balance

International Nuclear Information System (INIS)

Greene, Barry R; McGrath, Denise; Walsh, Lorcan; Doheny, Emer P; McKeown, David; Garattini, Chiara; Cunningham, Clodagh; Crosby, Lisa; Caulfield, Brian; Kenny, Rose A

2012-01-01

Falls are the most common cause of injury and hospitalization and one of the principal causes of death and disability in older adults worldwide. Measures of postural stability have been associated with the incidence of falls in older adults. The aim of this study was to develop a model that accurately classifies fallers and non-fallers using novel multi-sensor quantitative balance metrics that can be easily deployed into a home or clinic setting. We compared the classification accuracy of our model with an established method for falls risk assessment, the Berg balance scale. Data were acquired using two sensor modalities—a pressure sensitive platform sensor and a body-worn inertial sensor, mounted on the lower back—from 120 community dwelling older adults (65 with a history of falls, 55 without, mean age 73.7 ± 5.8 years, 63 female) while performing a number of standing balance tasks in a geriatric research clinic. Results obtained using a support vector machine yielded a mean classification accuracy of 71.52% (95% CI: 68.82–74.28) in classifying falls history, obtained using one model classifying all data points. Considering male and female participant data separately yielded classification accuracies of 72.80% (95% CI: 68.85–77.17) and 73.33% (95% CI: 69.88–76.81) respectively, leading to a mean classification accuracy of 73.07% in identifying participants with a history of falls. Results compare favourably to those obtained using the Berg balance scale (mean classification accuracy: 59.42% (95% CI: 56.96–61.88)). Results from the present study could lead to a robust method for assessing falls risk in both supervised and unsupervised environments. (paper)

Quantitative risk assessment of human salmonellosis in the smallholder pig value chains in urban of Vietnam.

Science.gov (United States)

Dang-Xuan, Sinh; Nguyen-Viet, Hung; Unger, Fred; Pham-Duc, Phuc; Grace, Delia; Tran-Thi, Ngan; Barot, Max; Pham-Thi, Ngoc; Makita, Kohei

2017-02-01

To quantify salmonellosis risk in humans through consumption of boiled pork in urban Hung Yen Province, Vietnam, using a quantitative microbial risk assessment. We collected 302 samples along the pork value chain in Hung Yen between April 2014 and February 2015. We developed a model in @Risk, based on microbiological, market, and household surveys on cooking, cross-contamination and consumption, and conducted sensitivity analysis. Salmonella prevalence of pen floor swabs, slaughterhouse carcasses and cut pork were 33.3, 41.7 and 44.4%, respectively. The annual incidence rate of salmonellosis in humans was estimated to be 17.7% (90% CI 0.89-45.96). Parameters with the greatest influence risk were household pork handling practice followed by prevalence in pork sold in the central market. Wide confidence interval in the incidence estimate was mainly due to the variability in the degree of reduction in bacteria concentration by cooking, and pork consumption pattern. The risk of salmonellosis in humans due to boiled pork consumption appears to be high. Control measures may include improving the safety of retailed pork and improving household hygiene.

Risk assessment of carcinogens in food

International Nuclear Information System (INIS)

Barlow, Susan; Schlatter, Josef

2010-01-01

Approaches for the risk assessment of carcinogens in food have evolved as scientific knowledge has advanced. Early methods allowed little more than hazard identification and an indication of carcinogenic potency. Evaluation of the modes of action of carcinogens and their broad division into genotoxic and epigenetic (non-genotoxic, non-DNA reactive) carcinogens have played an increasing role in determining the approach followed and provide possibilities for more detailed risk characterisation, including provision of quantitative estimates of risk. Reliance on experimental animal data for the majority of risk assessments and the fact that human exposures to dietary carcinogens are often orders of magnitude below doses used in experimental studies has provided a fertile ground for discussion and diverging views on the most appropriate way to offer risk assessment advice. Approaches used by national and international bodies differ, with some offering numerical estimates of potential risks to human health, while others express considerable reservations about the validity of quantitative approaches requiring extrapolation of dose-response data below the observed range and instead offer qualitative advice. Recognising that qualitative advice alone does not provide risk managers with information on which to prioritise the need for risk management actions, a 'margin of exposure' approach for substances that are both genotoxic and carcinogenic has been developed, which is now being used by the World Health Organization and the European Food Safety Authority. This review describes the evolution of risk assessment advice on carcinogens and discusses examples of ways in which carcinogens in food have been assessed in Europe.

Risk assessment of carcinogens in food.

Science.gov (United States)

Barlow, Susan; Schlatter, Josef

2010-03-01

Approaches for the risk assessment of carcinogens in food have evolved as scientific knowledge has advanced. Early methods allowed little more than hazard identification and an indication of carcinogenic potency. Evaluation of the modes of action of carcinogens and their broad division into genotoxic and epigenetic (non-genotoxic, non-DNA reactive) carcinogens have played an increasing role in determining the approach followed and provide possibilities for more detailed risk characterisation, including provision of quantitative estimates of risk. Reliance on experimental animal data for the majority of risk assessments and the fact that human exposures to dietary carcinogens are often orders of magnitude below doses used in experimental studies has provided a fertile ground for discussion and diverging views on the most appropriate way to offer risk assessment advice. Approaches used by national and international bodies differ, with some offering numerical estimates of potential risks to human health, while others express considerable reservations about the validity of quantitative approaches requiring extrapolation of dose-response data below the observed range and instead offer qualitative advice. Recognising that qualitative advice alone does not provide risk managers with information on which to prioritise the need for risk management actions, a "margin of exposure" approach for substances that are both genotoxic and carcinogenic has been developed, which is now being used by the World Health Organization and the European Food Safety Authority. This review describes the evolution of risk assessment advice on carcinogens and discusses examples of ways in which carcinogens in food have been assessed in Europe.

Rapid Quantification of Viable Campylobacter Bacteria on Chicken Carcasses, Using Real-Time PCR and Propidium Monoazide Treatment, as a Tool for Quantitative Risk Assessment

DEFF Research Database (Denmark)

Josefsen, Mathilde Hartmann; Löfström, Charlotta; Hansen, Tina Beck

2010-01-01

A number of intervention strategies against Campylobacter contaminated poultry focus on post-slaughter reduction of the number of cells, emphasizing the need for rapid and reliable quantitative detection of only viable Campylobacter. We present a new and rapid quantitative approach for enumeration...... method does not detect DNA from dead Campylobacter, but recognises the infectious potential of the VBNC state, and is thereby able to assess the effect of control strategies, and provide trustworthy data for risk assessment....

Quantitative assessments of indoor air pollution and the risk of childhood acute leukemia in Shanghai

International Nuclear Information System (INIS)

Gao, Yu; Zhang, Yan; Kamijima, Michihiro; Sakai, Kiyoshi; Khalequzzaman, Md; Nakajima, Tamie; Shi, Rong; Wang, Xiaojin; Chen, Didi; Ji, Xiaofan; Han, Kaiyi; Tian, Ying

2014-01-01

We investigated the association between indoor air pollutants and childhood acute leukemia (AL). A total of 105 newly diagnosed cases and 105 1:1 gender-, age-, and hospital-matched controls were included. Measurements of indoor pollutants (including nitrogen dioxide (NO 2 ) and 17 types of volatile organic compounds (VOCs)) were taken with diffusive samplers for 64 pairs of cases and controls. Higher concentrations of NO 2 and almost half of VOCs were observed in the cases than in the controls and were associated with the increased risk of childhood AL. The use of synthetic materials for wall decoration and furniture in bedroom was related to the risk of childhood AL. Renovating the house in the last 5 years, changing furniture in the last 5 years, closing the doors and windows overnight in the winter and/or summer, paternal smoking history and outdoor pollutants affected VOC concentrations. Our results support the association between childhood AL and indoor air pollution. - Highlights: • We firstly assessed the effects of indoor air pollution on childhood AL in China. • Indoor air pollutants were assessed by questionnaire and quantitative measurements. • NO 2 and 17 types of VOCs were measured in bedrooms of both cases and controls. • Higher concentrations of indoor air pollutants increased the risk of childhood AL. • Indoor behavioral factors and outdoor pollution might affect indoor air pollution. - Higher concentrations of indoor air pollutants were related to an elevated risk of childhood AL

Quantitative analysis and health risk assessment of polycyclic aromatic hydrocarbons in edible vegetable oils marketed in Shandong of China.

Science.gov (United States)

Jiang, Dafeng; Xin, Chenglong; Li, Wei; Chen, Jindong; Li, Fenghua; Chu, Zunhua; Xiao, Peirui; Shao, Lijun

2015-09-01

This work studies on the quantitative analysis and health risk assessment of polycyclic aromatic hydrocarbons (PAHs) in edible vegetable oils in Shandong, China. The concentrations of 15 PAHs in 242 samples were determined by high performance liquid chromatography coupled with fluorescence detection. The results indicated that the mean concentration of 15 PAHs in oil samples was 54.37 μg kg(-1). Low molecular weight PAH compounds were the predominant contamination. Especially, the carcinogenic benzo(a)pyrene (BaP) was detected at a mean concentration of 1.28 μg kg(-1), which was lower than the limit of European Union and China. A preliminary evaluation of human health risk assessment for PAHs was accomplished using BaP toxic equivalency factors and the incremental lifetime cancer risk (ILCR). The ILCR values for children, adolescents, adults, and seniors were all larger than 1 × 10(-6), indicating a high potential carcinogenic risk on the dietary exposed populations. Copyright © 2015 Elsevier Ltd. All rights reserved.

Predictive value of quantitative dipyridamole-thallium scintigraphy in assessing cardiovascular risk after vascular surgery in diabetes mellitus

International Nuclear Information System (INIS)

Lane, S.E.; Lewis, S.M.; Pippin, J.J.; Kosinski, E.J.; Campbell, D.; Nesto, R.W.; Hill, T.

1989-01-01

Cardiac complications represent a major risk to patients undergoing vascular surgery. Diabetic patients may be particularly prone to such complications due to the high incidence of concomitant coronary artery disease, the severity of which may be clinically unrecognized. Attempts to stratify groups by clinical criteria have been useful but lack the predictive value of currently used noninvasive techniques such as dipyridamole-thallium scintigraphy. One hundred one diabetic patients were evaluated with dipyridamole-thallium scintigraphy before undergoing vascular surgery. The incidence of thallium abnormalities was high (80%) and did not correlate with clinical markers of coronary disease. Even in a subgroup of patients with no overt clinical evidence of underlying heart disease, thallium abnormalities were present in 59%. Cardiovascular complications, however, occurred in only 11% of all patients. Statistically significant prediction of risk was not achieved with simple assessment of thallium results as normal or abnormal. Quantification of total number of reversible defects, as well as assessment of ischemia in the distribution of the left anterior descending coronary artery was required for optimum predictive accuracy. The prevalence of dipyridamole-thallium abnormalities in a diabetic population is much higher than that reported in nondiabetic patients and cannot be predicted by usual clinical indicators of heart disease. In addition, cardiovascular risk of vascular surgery can be optimally assessed by quantitative analysis of dipyridamole-thallium scintigraphy and identification of high- and low-risk subgroups

Risks, risk assessment and risk competence in toxicology.

Science.gov (United States)

Stahlmann, Ralf; Horvath, Aniko

2015-01-01

Understanding the toxic effects of xenobiotics requires sound knowledge of physiology and biochemistry. The often described lack of understanding pharmacology/toxicology is therefore primarily caused by the general absence of the necessary fundamental knowledge. Since toxic effects depend on exposure (or dosage) assessing the risks arising from toxic substances also requires quantitative reasoning. Typically public discussions nearly always neglect quantitative aspects and laypersons tend to disregard dose-effect-relationships. One of the main reasons for such disregard is the fact that exposures often occur at extremely low concentrations that can only be perceived intellectually but not by the human senses. However, thresholds in the low exposure range are often scientifically disputed. At the same time, ignorance towards known dangers is wide-spread. Thus, enhancing the risk competence of laypersons will have to be initially restricted to increasing the awareness of existing problems.

Comparison of recreational health risks associated with surfing and swimming in dry weather and post-storm conditions at Southern California beaches using quantitative microbial risk assessment (QMRA).

Science.gov (United States)

Tseng, Linda Y; Jiang, Sunny C

2012-05-01

Southern California is an increasingly urbanized hotspot for surfing, thus it is of great interest to assess the human illness risks associated with this popular ocean recreational water sport from exposure to fecal bacteria contaminated coastal waters. Quantitative microbial risk assessments were applied to eight popular Southern California beaches using readily available enterococcus and fecal coliform data and dose-response models to compare health risks associated with surfing during dry weather and storm conditions. The results showed that the level of gastrointestinal illness risks from surfing post-storm events was elevated, with the probability of exceeding the US EPA health risk guideline up to 28% of the time. The surfing risk was also elevated in comparison with swimming at the same beach due to ingestion of greater volume of water. The study suggests that refinement of dose-response model, improving monitoring practice and better surfer behavior surveillance will improve the risk estimation. Copyright © 2012 Elsevier Ltd. All rights reserved.

Risk assessment theory, methods, and applications

CERN Document Server

Rausand, Marvin

2011-01-01

With its balanced coverage of theory and applications along with standards and regulations, Risk Assessment: Theory, Methods, and Applications serves as a comprehensive introduction to the topic. The book serves as a practical guide to current risk analysis and risk assessment, emphasizing the possibility of sudden, major accidents across various areas of practice from machinery and manufacturing processes to nuclear power plants and transportation systems. The author applies a uniform framework to the discussion of each method, setting forth clear objectives and descriptions, while also shedding light on applications, essential resources, and advantages and disadvantages. Following an introduction that provides an overview of risk assessment, the book is organized into two sections that outline key theory, methods, and applications. * Introduction to Risk Assessment defines key concepts and details the steps of a thorough risk assessment along with the necessary quantitative risk measures. Chapters outline...

[Risk assessment and risk control for occupational exposure to chemical toxicants from an isophorone nitrile device].

Science.gov (United States)

Wang, Dejun; Fu, Xiaokuan; Kong, Fanling; Sui, Shaofeng; Jiang, Yuanyuan; Du, Yinglin; Zhou, Jingyang

2014-06-01

Risk assessment and risk control for occupational exposure to chemical toxicants were performed on an isophorone nitrile device with an annual production of 5,000 tons, based on improved Singaporean semi-quantitative risk assessment method, with consideration of actual situation in China and in the present project. With the use of engineering analysis and identification of occupational hazards in the improved Singaporean semi-quantitative risk assessment method, hazard rating (HR) and risk assessment were performed on chemical toxicants from an isophorone nitrile device with an annual production of 5,000 tons. The chemical toxicants in the isophorone nitrile device were mainly isophorone, hydrocyanic acid, methanol, phosphoric acid, sodium hydroxide, and sodium cyanide; the HR values were mild hazard (2), extreme hazard (5), mild hazard (2), mild hazard (2), moderate hazard (3), and extreme hazard (5), respectively, and the corresponding exposure rating (ER) values were 2.09, 2.72, 2.76, 1.68, 2.0, and 1.59, respectively. The risk of chemical toxicants in this project was assessed according to the formula Risk = [HR×ER](1/2). Hydrocyanic acid was determined as high risk, sodium hydroxide and sodium cyanide as medium risk, and isophorone, methanol, and phosphoric acid as low risk. Priority in handling of risks was determined by risk rating. The table of risk control measure was established for pre-assessment of occupational hazards. With risk assessment in this study, we concluded that the isophorone nitrile device with 5,000 ton annual production was a high-occupational hazard device. This device is a project of extreme occupational hazard. The improved Singaporean semi-quantitative risk assessment method is a scientific and applicable method, and is especially suitable for pre-evaluation of on-site project with no analogy.

Quantitative risk in radiation protection standards

International Nuclear Information System (INIS)

Bond, V.P.

1979-01-01

Although the overall aim of radiobiology is to understand the biological effects of radiation, it also has the implied practical purpose of developing rational measures for the control of radiation exposure in man. The emphasis in this presentation is to show that the enormous effort expended over the years to develop quantitative dose-effect relationships in biochemical and cellular systems, animals, and human beings now seems to be paying off. The pieces appear to be falling into place, and a framework is evolving to utilize these data. Specifically, quantitative risk assessments will be discussed in terms of the cellular, animal, and human data on which they are based; their use in the development of radiation protection standards; and their present and potential impact and meaning in relation to the quantity dose equivalent and its special unit, the rem

N reactor individual risk comparison to quantitative nuclear safety goals

International Nuclear Information System (INIS)

Wang, O.S.; Rainey, T.E.; Zentner, M.D.

1990-01-01

A full-scope level III probabilistic risk assessment (PRA) has been completed for N reactor, a US Department of Energy (DOE) production reactor located on the Hanford Reservation in the state of Washington. Sandia National Laboratories (SNL) provided the technical leadership for this work, using the state-of-the-art NUREG-1150 methodology developed for the US Nuclear Regulatory Commission (NRC). The main objectives of this effort were to assess the risks to the public and to the on-site workers posed by the operation of N reactor, to identify changes to the plant that could reduce the overall risk, and to compare those risks to the proposed NRC and DOE quantitative safety goals. This paper presents the methodology adopted by Westinghouse Hanford Company (WHC) and SNL for individual health risk evaluation, its results, and a comparison to the NRC safety objectives and the DOE nuclear safety guidelines. The N reactor results, are also compared with the five NUREG-1150 nuclear plants. Only internal events are compared here because external events are not yet reported in the current draft NUREG-1150. This is the first full-scope level III PRA study with a detailed quantitative safety goal comparison performed for DOE production reactors

Modeling number of bacteria per food unit in comparison to bacterial concentration in quantitative risk assessment: impact on risk estimates.

Science.gov (United States)

Pouillot, Régis; Chen, Yuhuan; Hoelzer, Karin

2015-02-01

When developing quantitative risk assessment models, a fundamental consideration for risk assessors is to decide whether to evaluate changes in bacterial levels in terms of concentrations or in terms of bacterial numbers. Although modeling bacteria in terms of integer numbers may be regarded as a more intuitive and rigorous choice, modeling bacterial concentrations is more popular as it is generally less mathematically complex. We tested three different modeling approaches in a simulation study. The first approach considered bacterial concentrations; the second considered the number of bacteria in contaminated units, and the third considered the expected number of bacteria in contaminated units. Simulation results indicate that modeling concentrations tends to overestimate risk compared to modeling the number of bacteria. A sensitivity analysis using a regression tree suggests that processes which include drastic scenarios consisting of combinations of large bacterial inactivation followed by large bacterial growth frequently lead to a >10-fold overestimation of the average risk when modeling concentrations as opposed to bacterial numbers. Alternatively, the approach of modeling the expected number of bacteria in positive units generates results similar to the second method and is easier to use, thus potentially representing a promising compromise. Published by Elsevier Ltd.

Quantitative Metrics and Risk Assessment: The Three Tenets Model of Cybersecurity

Directory of Open Access Journals (Sweden)

Jeff Hughes

2013-08-01

Full Text Available Progress in operational cybersecurity has been difficult to demonstrate. In spite of the considerable research and development investments made for more than 30 years, many government, industrial, financial, and consumer information systems continue to be successfully attacked and exploited on a routine basis. One of the main reasons that progress has been so meagre is that most technical cybersecurity solutions that have been proposed to-date have been point solutions that fail to address operational tradeoffs, implementation costs, and consequent adversary adaptations across the full spectrum of vulnerabilities. Furthermore, sound prescriptive security principles previously established, such as the Orange Book, have been difficult to apply given current system complexity and acquisition approaches. To address these issues, the authors have developed threat-based descriptive methodologies to more completely identify system vulnerabilities, to quantify the effectiveness of possible protections against those vulnerabilities, and to evaluate operational consequences and tradeoffs of possible protections. This article begins with a discussion of the tradeoffs among seemingly different system security properties such as confidentiality, integrity, and availability. We develop a quantitative framework for understanding these tradeoffs and the issues that arise when those security properties are all in play within an organization. Once security goals and candidate protections are identified, risk/benefit assessments can be performed using a novel multidisciplinary approach, called “QuERIES.” The article ends with a threat-driven quantitative methodology, called “The Three Tenets”, for identifying vulnerabilities and countermeasures in networked cyber-physical systems. The goal of this article is to offer operational guidance, based on the techniques presented here, for informed decision making about cyber-physical system security.

Information security risk assessment, aggregation, and mitigation

NARCIS (Netherlands)

Lenstra, A.K.; Voss, T.; Wang, H.; Pieprzyk, J.; Varadharajan, V.

2004-01-01

As part of their compliance process with the Basel 2 operational risk management requirements, banks must define how they deal with information security risk management. In this paper we describe work in progress on a new quantitative model to assess and aggregate information security risks that is

Web Applications Vulnerability Management using a Quantitative Stochastic Risk Modeling Method

Directory of Open Access Journals (Sweden)

Sergiu SECHEL

2017-01-01

Full Text Available The aim of this research is to propose a quantitative risk modeling method that reduces the guess work and uncertainty from the vulnerability and risk assessment activities of web based applications while providing users the flexibility to assess risk according to their risk appetite and tolerance with a high degree of assurance. The research method is based on the research done by the OWASP Foundation on this subject but their risk rating methodology needed de-bugging and updates in different in key areas that are presented in this paper. The modified risk modeling method uses Monte Carlo simulations to model risk characteristics that can’t be determined without guess work and it was tested in vulnerability assessment activities on real production systems and in theory by assigning discrete uniform assumptions to all risk charac-teristics (risk attributes and evaluate the results after 1.5 million rounds of Monte Carlo simu-lations.

Risks, risk assessment and risk competence in toxicology

Science.gov (United States)

Stahlmann, Ralf; Horvath, Aniko

2015-01-01

Understanding the toxic effects of xenobiotics requires sound knowledge of physiology and biochemistry. The often described lack of understanding pharmacology/toxicology is therefore primarily caused by the general absence of the necessary fundamental knowledge. Since toxic effects depend on exposure (or dosage) assessing the risks arising from toxic substances also requires quantitative reasoning. Typically public discussions nearly always neglect quantitative aspects and laypersons tend to disregard dose-effect-relationships. One of the main reasons for such disregard is the fact that exposures often occur at extremely low concentrations that can only be perceived intellectually but not by the human senses. However, thresholds in the low exposure range are often scientifically disputed. At the same time, ignorance towards known dangers is wide-spread. Thus, enhancing the risk competence of laypersons will have to be initially restricted to increasing the awareness of existing problems. PMID:26195922

Risks, risk assessment and risk competence in toxicology

Directory of Open Access Journals (Sweden)

Stahlmann, Ralf

2015-07-01

Full Text Available Understanding the toxic effects of xenobiotics requires sound knowledge of physiology and biochemistry. The often described lack of understanding pharmacology/toxicology is therefore primarily caused by the general absence of the necessary fundamental knowledge. Since toxic effects depend on exposure (or dosage assessing the risks arising from toxic substances also requires quantitative reasoning. Typically public discussions nearly always neglect quantitative aspects and laypersons tend to disregard dose-effect-relationships. One of the main reasons for such disregard is the fact that exposures often occur at extremely low concentrations that can only be perceived intellectually but not by the human senses. However, thresholds in the low exposure range are often scientifically disputed. At the same time, ignorance towards known dangers is wide-spread. Thus, enhancing the risk competence of laypersons will have to be initially restricted to increasing the awareness of existing problems.

Multiple-Strain Approach and Probabilistic Modeling of Consumer Habits in Quantitative Microbial Risk Assessment: A Quantitative Assessment of Exposure to Staphylococcal Enterotoxin A in Raw Milk.

Science.gov (United States)

Crotta, Matteo; Rizzi, Rita; Varisco, Giorgio; Daminelli, Paolo; Cunico, Elena Cosciani; Luini, Mario; Graber, Hans Ulrich; Paterlini, Franco; Guitian, Javier

2016-03-01

Quantitative microbial risk assessment (QMRA) models are extensively applied to inform management of a broad range of food safety risks. Inevitably, QMRA modeling involves an element of simplification of the biological process of interest. Two features that are frequently simplified or disregarded are the pathogenicity of multiple strains of a single pathogen and consumer behavior at the household level. In this study, we developed a QMRA model with a multiple-strain approach and a consumer phase module (CPM) based on uncertainty distributions fitted from field data. We modeled exposure to staphylococcal enterotoxin A in raw milk in Lombardy; a specific enterotoxin production module was thus included. The model is adaptable and could be used to assess the risk related to other pathogens in raw milk as well as other staphylococcal enterotoxins. The multiplestrain approach, implemented as a multinomial process, allowed the inclusion of variability and uncertainty with regard to pathogenicity at the bacterial level. Data from 301 questionnaires submitted to raw milk consumers were used to obtain uncertainty distributions for the CPM. The distributions were modeled to be easily updatable with further data or evidence. The sources of uncertainty due to the multiple-strain approach and the CPM were identified, and their impact on the output was assessed by comparing specific scenarios to the baseline. When the distributions reflecting the uncertainty in consumer behavior were fixed to the 95th percentile, the risk of exposure increased up to 160 times. This reflects the importance of taking into consideration the diversity of consumers' habits at the household level and the impact that the lack of knowledge about variables in the CPM can have on the final QMRA estimates. The multiple-strain approach lends itself to use in other food matrices besides raw milk and allows the model to better capture the complexity of the real world and to be capable of geographical

Quantitative Microbial Risk Assessment for Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes in Leafy Green Vegetables Consumed at Salad Bars, Based on Modeling Supply Chain Logistics

NARCIS (Netherlands)

Tromp, S.O.; Rijgersberg, H.; Franz, E.

2010-01-01

Quantitative microbial risk assessments do not usually account for the planning and ordering mechanisms (logistics) of a food supply chain. These mechanisms and consumer demand determine the storage and delay times of products. The aim of this study was to quantitatively assess the difference

Breach Risk Magnitude: A Quantitative Measure of Database Security.

Science.gov (United States)

Yasnoff, William A

2016-01-01

A quantitative methodology is described that provides objective evaluation of the potential for health record system breaches. It assumes that breach risk increases with the number of potential records that could be exposed, while it decreases when more authentication steps are required for access. The breach risk magnitude (BRM) is the maximum value for any system user of the common logarithm of the number of accessible database records divided by the number of authentication steps needed to achieve such access. For a one million record relational database, the BRM varies from 5.52 to 6 depending on authentication protocols. For an alternative data architecture designed specifically to increase security by separately storing and encrypting each patient record, the BRM ranges from 1.3 to 2.6. While the BRM only provides a limited quantitative assessment of breach risk, it may be useful to objectively evaluate the security implications of alternative database organization approaches.

Avalanche risk assessment in Russia

Science.gov (United States)

Komarov, Anton; Seliverstov, Yury; Sokratov, Sergey; Glazovskaya, Tatiana; Turchaniniva, Alla

2017-04-01

. The case studies of specific territories are performed using large-scale risk assessment methods. Thus, we discuss these problems by presenting an avalanche risk assessment approach on example of the developing but poorly researched ski resort areas in the North Caucasus. The suggested method includes the formulas to calculate collective and individual avalanche risk. The results of risk analysis are shown in quantitative data that can be used to determine levels of avalanche risk (acceptable, admissible and unacceptable) and to suggest methods to decrease the individual risk to acceptable level or better. It makes possible to compare risk quantitative data obtained from different mountain regions, analyze it and evaluate the economic feasibility of protection measures. At present, we are developing methods of avalanche risk assessment in economic performance. It conceder costs of objects located in avalanche prone area, traffic density values and probability of financial loss.

Extracting additional risk managers information from a risk assessment of Listeria monocytogenes in deli meats

NARCIS (Netherlands)

Pérez-Rodríguez, F.; Asselt, van E.D.; García-Gimeno, R.M.; Zurera, G.; Zwietering, M.H.

2007-01-01

The risk assessment study of Listeria monocytogenes in ready-to-eat foods conducted by the U.S. Food and Drug Administration is an example of an extensive quantitative microbiological risk assessment that could be used by risk analysts and other scientists to obtain information and by managers and

Effects of a 20 year rain event: a quantitative microbial risk assessment of a case of contaminated bathing water in Copenhagen, Denmark

DEFF Research Database (Denmark)

Andersen, Signe Tanja; Erichsen, A. C.; Mark, O.

2013-01-01

Quantitative microbial risk assessments (QMRAs) often lack data on water quality leading to great uncertainty in the QMRA because of the many assumptions. The quantity of waste water contamination was estimated and included in a QMRA on an extreme rain event leading to combined sewer overflow (CS...

A risk assessment-driven quantitative comparison of gene expression profiles in PBMCs and white adipose tissue of humans and rats after isoflavone supplementation

NARCIS (Netherlands)

Velpen, van der V.; Veer, van 't P.; Islam, M.A.; Braak, ter C.J.F.; Leeuwen, F.X.R.; Afman, L.A.; Hollman, P.C.H.; Schouten, A.; Geelen, M.M.E.E.

2016-01-01

Quantitative insight into species differences in risk assessment is expected to reduce uncertainty and variability related to extrapolation from animals to humans. This paper explores quantification and comparison of gene expression data between tissues and species from intervention studies with

A quantitative assessment of risks of heavy metal residues in laundered shop towels and their use by workers.

Science.gov (United States)

Connor, Kevin; Magee, Brian

2014-10-01

This paper presents a risk assessment of exposure to metal residues in laundered shop towels by workers. The concentrations of 27 metals measured in a synthetic sweat leachate were used to estimate the releasable quantity of metals which could be transferred to workers' skin. Worker exposure was evaluated quantitatively with an exposure model that focused on towel-to-hand transfer and subsequent hand-to-food or -mouth transfers. The exposure model was based on conservative, but reasonable assumptions regarding towel use and default exposure factor values from the published literature or regulatory guidance. Transfer coefficients were derived from studies representative of the exposures to towel users. Contact frequencies were based on assumed high-end use of shop towels, but constrained by a theoretical maximum dermal loading. The risk estimates for workers developed for all metals were below applicable regulatory risk benchmarks. The risk assessment for lead utilized the Adult Lead Model and concluded that predicted lead intakes do not constitute a significant health hazard based on potential worker exposures. Uncertainties are discussed in relation to the overall confidence in the exposure estimates developed for each exposure pathway and the likelihood that the exposure model is under- or overestimating worker exposures and risk. Copyright © 2014 Elsevier Inc. All rights reserved.

Risk assessment and food allergy: the probabilistic model applied to allergens

NARCIS (Netherlands)

Spanjersberg, M.Q.I.; Kruizinga, A.G.; Rennen, M.A.J.; Houben, G.F.

2007-01-01

In order to assess the risk of unintended exposure to food allergens, traditional deterministic risk assessment is usually applied, leading to inconsequential conclusions as 'an allergic reaction cannot be excluded'. TNO therefore developed a quantitative risk assessment model for allergens based on

Quantitative assessment of breast density from mammograms

International Nuclear Information System (INIS)

Jamal, N.; Ng, K.H.

2004-01-01

Full text: It is known that breast density is increasingly used as a risk factor for breast cancer. This study was undertaken to develop and validate a semi-automated computer technique for the quantitative assessment of breast density from digitised mammograms. A computer technique had been developed using MATLAB (Version 6.1) based GUI applications. This semi-automated image analysis tool consists of gradient correction, segmentation of breast region from background, segmentation of fibroglandular and adipose region within the breast area and calculation of breast density. The density is defined as the percentage of fibroglandular tissue area divided by the total breast area in the mammogram. This technique was clinically validated with 122 normal mammograms; these were subjectively evaluated and classified according to the five parenchyma patterns of the Tabar's scheme (Class I- V) by a consultant radiologist. There was a statistical significant correlation between the computer technique and subjective classification (r 2 = 0.84, p<0.05). 71.3% of subjective classification was correctly classified using the computer technique. We had developed a computer technique for the quantitative assessment of breast density and validated its accuracy for computerized classification based on Tabar's scheme. This quantitative tool is useful for the evaluation of a large dataset of mammograms to predict breast cancer risk based on density. Furthermore it has the potential to provide an early marker for success or failure in chemoprevention studies such as hormonal replacement therapy. Copyright (2004) Australasian College of Physical Scientists and Engineers in Medicine

Risk assessment - a research program aimed at health risks from air pollution in the general environment

International Nuclear Information System (INIS)

Lindahl-Kiessling, K.; Ahlborg, U.; Bylin, G.; Ehrenberg, L.; Hemminki, K.; Lindell, B.; Nilsson, Robert; Bostroem, C.E.; Swarn, U.

1991-01-01

The paper presents a new research program for assessment of health risks caused by air pollutants. It is important to develop general methods for quantitative risk assessments and to improve the scientific base materials. (KAE)

Quantitative evaluation of the impact of human reliability in risk assessment for nuclear power plants

International Nuclear Information System (INIS)

Samanta, P.K.

1981-01-01

The role of human beings in the safe operation of a nuclear power plant has been a matter of concern. This study describes methods for the quantitative description of that role and its impact on the risk from nuclear power plants. The impact of human errors was calculated by observing the changes in risk parameters, such as core melt probability, release category probabilities, accident sequence probabilities and system unavailabilities due to changes in the contribution to unavailablity of human errors, within the framework of risk assessment methodology. It was found that for operational pressurized water reactors the opportunity for reduction in core melt probability by reducing the human error rates without simultaneous reduction of hardware failures is limited, but that core melt probability would significantly increase as human error rates increased. More importantly, most of the dominant accident sequences showed a significant increase in their probabilities with an increase in human error rates. Release categories resulting in high consequences showed a much larger sensitivity to human errors than categories resulting in low consequences. A combination of structural importance and reliability importance measure was used to describe the importance of individual errors

Probabilistic quantitative microbial risk assessment model of norovirus from wastewater irrigated vegetables in Ghana using genome copies and fecal indicator ratio conversion for estimating exposure dose

DEFF Research Database (Denmark)

Owusu-Ansah, Emmanuel de-Graft Johnson; Sampson, Angelina; Amponsah, Samuel K.

2017-01-01

physical and environmental factors that might influence the reliability of using indicator organisms in microbial risk assessment. The challenges facing analytical studies on virus enumeration (genome copies or particles) have contributed to the already existing lack of data in QMRA modelling. This study......The need to replace the commonly applied fecal indicator conversions ratio (an assumption of 1:10− 5 virus to fecal indicator organism) in Quantitative Microbial Risk Assessment (QMRA) with models based on quantitative data on the virus of interest has gained prominence due to the different...... attempts to fit a QMRA model to genome copies of norovirus data. The model estimates the risk of norovirus infection from the intake of vegetables irrigated with wastewater from different sources. The results were compared to the results of a corresponding model using the fecal indicator conversion ratio...

Skin sensitisation quantitative risk assessment (QRA) based on aggregate dermal exposure to methylisothiazolinone in personal care and household cleaning products.

Science.gov (United States)

Ezendam, J; Bokkers, B G H; Bil, W; Delmaar, J E

2018-02-01

Contact allergy to preservatives is an important public health problem. Ideally, new substances should be evaluated for the risk on skin sensitisation before market entry, for example by using a quantitative risk assessment (QRA) as developed for fragrances. As a proof-of-concept, this QRA was applied to the preservative methylisothiazolinone (MI), a common cause of contact allergy. MI is used in different consumer products, including personal care products (PCPs) and household cleaning products (HCPs). Aggregate exposure to MI in PCPs and HCPs was therefore assessed with the Probabilistic Aggregated Consumer Exposure Model (PACEM). Two exposure scenarios were evaluated: scenario 1 calculated aggregate exposure on actual MI product concentrations before the restricted use in PCPs and scenario 2 calculated aggregate exposure using the restrictions for MI in PCPs. The QRA for MI showed that in scenarios 1 and 2, the proportion of the population at risk for skin sensitisation is 0.7% and 0.5%, respectively. The restricted use of MI in PCPs does not seem very effective in lowering the risk on skin sensitization. To conclude, it is important to consider aggregate exposure from the most important consumer products into consideration in the risk assessment. Copyright © 2018 Elsevier Ltd. All rights reserved.

Tools for Microbiological risk assessment

DEFF Research Database (Denmark)

Bassett, john; Nauta, Maarten; Lindqvist, Roland

can increase the understanding of microbiological risks in foods. It is timely to inform food safety professionals about the availability and utility of MRA tools. Therefore, the focus of this report is to aid the food safety manager by providing a concise summary of the tools available for the MRA......Microbiological Risk Assessment (MRA) has emerged as a comprehensive and systematic approach for addressing the risk of pathogens in specific foods and/or processes. At government level, MRA is increasingly recognised as a structured and objective approach to understand the level of risk in a given...... food/pathogen scenario. Tools developed so far support qualitative and quantitative assessments of the risk that a food pathogen poses to a particular population. Risk can be expressed as absolute numbers or as relative (ranked) risks. The food industry is beginning to appreciate that the tools for MRA...

Risk assessment techniques with applicability in marine engineering

Science.gov (United States)

Rudenko, E.; Panaitescu, F. V.; Panaitescu, M.

2015-11-01

Nowadays risk management is a carefully planned process. The task of risk management is organically woven into the general problem of increasing the efficiency of business. Passive attitude to risk and awareness of its existence are replaced by active management techniques. Risk assessment is one of the most important stages of risk management, since for risk management it is necessary first to analyze and evaluate risk. There are many definitions of this notion but in general case risk assessment refers to the systematic process of identifying the factors and types of risk and their quantitative assessment, i.e. risk analysis methodology combines mutually complementary quantitative and qualitative approaches. Purpose of the work: In this paper we will consider as risk assessment technique Fault Tree analysis (FTA). The objectives are: understand purpose of FTA, understand and apply rules of Boolean algebra, analyse a simple system using FTA, FTA advantages and disadvantages. Research and methodology: The main purpose is to help identify potential causes of system failures before the failures actually occur. We can evaluate the probability of the Top event.The steps of this analize are: the system's examination from Top to Down, the use of symbols to represent events, the use of mathematical tools for critical areas, the use of Fault tree logic diagrams to identify the cause of the Top event. Results: In the finally of study it will be obtained: critical areas, Fault tree logical diagrams and the probability of the Top event. These results can be used for the risk assessment analyses.

THE MODEL FOR RISK ASSESSMENT ERP-SYSTEMS INFORMATION SECURITY

Directory of Open Access Journals (Sweden)

V. S. Oladko

2016-12-01

Full Text Available The article deals with the problem assessment of information security risks in the ERP-system. ERP-system functions and architecture are studied. The model malicious impacts on levels of ERP-system architecture are composed. Model-based risk assessment, which is the quantitative and qualitative approach to risk assessment, built on the partial unification 3 methods for studying the risks of information security - security models with full overlapping technique CRAMM and FRAP techniques developed.

Quantitative Microbial Risk Assessment for in Natural and Processed Cheeses

Directory of Open Access Journals (Sweden)

Heeyoung Lee

2016-08-01

Full Text Available This study evaluated the risk of Clostridium perfringens (C. perfringens foodborne illness from natural and processed cheeses. Microbial risk assessment in this study was conducted according to four steps: hazard identification, hazard characterization, exposure assessment, and risk characterization. The hazard identification of C. perfringens on cheese was identified through literature, and dose response models were utilized for hazard characterization of the pathogen. For exposure assessment, the prevalence of C. perfringens, storage temperatures, storage time, and annual amounts of cheese consumption were surveyed. Eventually, a simulation model was developed using the collected data and the simulation result was used to estimate the probability of C. perfringens foodborne illness by cheese consumption with @RISK. C. perfringens was determined to be low risk on cheese based on hazard identification, and the exponential model (r = 1.82×10−11 was deemed appropriate for hazard characterization. Annual amounts of natural and processed cheese consumption were 12.40±19.43 g and 19.46±14.39 g, respectively. Since the contamination levels of C. perfringens on natural (0.30 Log CFU/g and processed cheeses (0.45 Log CFU/g were below the detection limit, the initial contamination levels of natural and processed cheeses were estimated by beta distribution (α1 = 1, α2 = 91; α1 = 1, α2 = 309×uniform distribution (a = 0, b = 2; a = 0, b = 2.8 to be −2.35 and −2.73 Log CFU/g, respectively. Moreover, no growth of C. perfringens was observed for exposure assessment to simulated conditions of distribution and storage. These data were used for risk characterization by a simulation model, and the mean values of the probability of C. perfringens foodborne illness by cheese consumption per person per day for natural and processed cheeses were 9.57×10−14 and 3.58×10−14, respectively. These results indicate that probability of C. perfringens

Comparative risk assessments for Guadeloupe: earthquakes and storm surge

OpenAIRE

Réveillère , Arnaud; Monfort , Daniel; Lecacheux , Sophie; Grisanti , Ludovic; Muller , Héloise; Bertil , Didier; Rohmer , Jérémy; Sedan , Olivier; Douglas , John; Baills , Audrey; Modaressi , Hormoz

2012-01-01

In France, risk assessments for natural hazards are usually carried out separately and decision makers lack comprehensive information. Moreover, since the cause of the hazard (e.g. meteorological, geological) and the physical phenomenon that causes damage (e.g. inundation, ground shaking) may be fundamentally different, the quantitative comparison of single risk assessments that were not conducted in a compatible framework is not straightforward. Comprehensive comparative risk assessments exi...

Applying quantitative benefit-risk analysis to aid regulatory decision making in diagnostic imaging: methods, challenges, and opportunities.

Science.gov (United States)

Agapova, Maria; Devine, Emily Beth; Bresnahan, Brian W; Higashi, Mitchell K; Garrison, Louis P

2014-09-01

Health agencies making regulatory marketing-authorization decisions use qualitative and quantitative approaches to assess expected benefits and expected risks associated with medical interventions. There is, however, no universal standard approach that regulatory agencies consistently use to conduct benefit-risk assessment (BRA) for pharmaceuticals or medical devices, including for imaging technologies. Economics, health services research, and health outcomes research use quantitative approaches to elicit preferences of stakeholders, identify priorities, and model health conditions and health intervention effects. Challenges to BRA in medical devices are outlined, highlighting additional barriers in radiology. Three quantitative methods--multi-criteria decision analysis, health outcomes modeling and stated-choice survey--are assessed using criteria that are important in balancing benefits and risks of medical devices and imaging technologies. To be useful in regulatory BRA, quantitative methods need to: aggregate multiple benefits and risks, incorporate qualitative considerations, account for uncertainty, and make clear whose preferences/priorities are being used. Each quantitative method performs differently across these criteria and little is known about how BRA estimates and conclusions vary by approach. While no specific quantitative method is likely to be the strongest in all of the important areas, quantitative methods may have a place in BRA of medical devices and radiology. Quantitative BRA approaches have been more widely applied in medicines, with fewer BRAs in devices. Despite substantial differences in characteristics of pharmaceuticals and devices, BRA methods may be as applicable to medical devices and imaging technologies as they are to pharmaceuticals. Further research to guide the development and selection of quantitative BRA methods for medical devices and imaging technologies is needed. Copyright © 2014 AUR. Published by Elsevier Inc. All rights

Quantitative assessment of breast density from digitized mammograms into Tabar's patterns

International Nuclear Information System (INIS)

Jamal, N; Ng, K-H; Looi, L-M; McLean, D; Zulfiqar, A; Tan, S-P; Liew, W-F; Shantini, A; Ranganathan, S

2006-01-01

We describe a semi-automated technique for the quantitative assessment of breast density from digitized mammograms in comparison with patterns suggested by Tabar. It was developed using the MATLAB-based graphical user interface applications. It is based on an interactive thresholding method, after a short automated method that shows the fibroglandular tissue area, breast area and breast density each time new thresholds are placed on the image. The breast density is taken as a percentage of the fibroglandular tissue to the breast tissue areas. It was tested in four different ways, namely by examining: (i) correlation of the quantitative assessment results with subjective classification, (ii) classification performance using the quantitative assessment technique, (iii) interobserver agreement and (iv) intraobserver agreement. The results of the quantitative assessment correlated well (r 2 = 0.92) with the subjective Tabar patterns classified by the radiologist (correctly classified 83% of digitized mammograms). The average kappa coefficient for the agreement between the readers was 0.63. This indicated moderate agreement between the three observers in classifying breast density using the quantitative assessment technique. The kappa coefficient of 0.75 for intraobserver agreement reflected good agreement between two sets of readings. The technique may be useful as a supplement to the radiologist's assessment in classifying mammograms into Tabar's pattern associated with breast cancer risk

Quantitative Microbial Risk Assessment for Escherichia coli O157 : H7, Salmonella, and Listeria monocytogenes in Leafy Green Vegetables Consumed at Salad Bars

NARCIS (Netherlands)

Franz, E.; Tromp, S.O.; Rijgersberg, H.; Fels-Klerx, van der H.J.

2010-01-01

Fresh vegetables are increasingly recognized as a source of foodborne outbreaks in many parts of the world. The purpose of this study was to conduct a quantitative microbial risk assessment for Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes infection from consumption of leafy green

Designing SQCRA as a Software to Semi-quantitative Chemical Risk Assessment in Workplace

Directory of Open Access Journals (Sweden)

Ali Karimi

2014-06-01

Full Text Available Background & Objectives : The aim of chemical risk assessment is to identify and evaluate risks originated from chemicals usages. This study aims to design a practical tool for facilitating chemical risk assessment. Methods: The proposed software was derived from chemical risk assessment method which was recommended by Ministry of Human Resources of Malaysia. All of the processes in question are designed in operating system software. Based on some revisions, this software was developed using Visual Basic (VB titled as SQCRA. The developed software was used for chemical risk assessment in Narges Vegetale Oil Company in Shiraz (center of Iran. Result: The output of software showed that the level of risk derived from sulfuric acid, phosphoric acid, aluminum sulphate, nickel catalyst, acetic acid used as a raw material were 2.4, 2.84, 2.3, 3.5 and 2.66, respectively. Moreover, risk rank and proposed control methods for each of these materials were determined. Conclusions : The developed software calculates the health risk level based on the degree of hazard and exposure in shorttime and without using risk matrix and chemical formula. After determining the risk rank, the software proposes the control procedures to reduce occupational exposure.

Ecotoxicological, ecophysiological, and biogeochemical fundamentals of risk assessment

International Nuclear Information System (INIS)

Bashkin, V.N.; Kozlov, M.Ya.; Evstafjeva, E.V.

1993-01-01

Risk assessment (RA) influenced by different factors in radionuclide polluted regions is carried out by determining the biogeochemical structure of a region. Consequently, ecological-biogeochemical regionalization, ecotoxicological and ecophysiological monitoring of human population health are the important approach to RA. These criteria should conjugate with LCA of various industrial and agricultural products. Given fundamentals and approaches are needed for areas where traditional pollutants (heavy metals, pesticides, fertilizers, POPs etc) are enforced sharply by radioactive pollution. For RA of these complex pollutants, the methods of human adaptability to a polluted environment have been carried out. These techniques include biogeochemical, ecotoxicological, and ecophysiological analyses of risk factors as well as quantitative analysis of uncertainties using expert-modeling systems. Furthermore, the modern statistical methods are used for quantitative assessment of human adaptability to radioactive and nonradioactive pollutants. The results obtained in Chernobyl regions show the acceptability of these methods for risk assessment

Ecotoxicological, ecophysiological and biogeochemical fundamentals of risk assessment

International Nuclear Information System (INIS)

Bashkin, V.; Evstafjeva, E.

1995-01-01

A quantitative risk assessment (RA) for complex influence of different factors in heavy polluted regions is possible to carry out only on a basis of determination of various links of biogeochemical trophical chains and analysis of the whole biogeochemical structure of the region under study. As an integrative assessment, the human adaptability should be chosen because the majority of trophical chains are closed by man. The given integrative criteria includes biogeochemical, ecophysiological and ecotoxicological assessment of risk factors. Consequently, ecological-biogeochemical regionalization, ecophysiological and ecotoxicological monitoring of human population health are the important approaches to RA. These criteria should be conjugated with LCA of various industrial and agricultural products. At the ultimate degree, the given approaches are needed for areas where traditional pollutants (heavy metals, POPS, pesticides, fertilizers) are enforced sharply by radioactive pollution. Due to the complex influence of pollutants, it is impossible to use individual guidelines. For RA of these complex pollutants, the methods of human adaptability assessment to a polluted environment have to be carried out. These methods include biogeochemical, ecotoxicological and ecophysiological analysis of risk factors as well as quantitative uncertainty analysis. Furthermore, the modern statistical methods such as correlative graphs etc., have to be used for quantitative assessment of human adaptability to complex influence of pollutants. The results obtained in the Chernobyl region have shown the acceptability of suggested methods

QUANTITATION OF MOLECULAR ENDPOINTS FOR THE DOSE-RESPONSE COMPONENT OF CANCER RISK ASSESSMENT

Science.gov (United States)

Cancer risk assessment involves the steps of hazard identification, dose-response assessment, exposure assessment and risk characterization. The rapid advances in the use of molecular biology approaches has had an impact on all four components, but the greatest overall current...

Supplemental Hazard Analysis and Risk Assessment - Hydrotreater

Energy Technology Data Exchange (ETDEWEB)

Lowry, Peter P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wagner, Katie A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2015-04-01

A supplemental hazard analysis was conducted and quantitative risk assessment performed in response to an independent review comment received by the Pacific Northwest National Laboratory (PNNL) from the U.S. Department of Energy Pacific Northwest Field Office (PNSO) against the Hydrotreater/Distillation Column Hazard Analysis Report issued in April 2013. The supplemental analysis used the hazardous conditions documented by the previous April 2013 report as a basis. The conditions were screened and grouped for the purpose of identifying whether additional prudent, practical hazard controls could be identified, using a quantitative risk evaluation to assess the adequacy of the controls and establish a lower level of concern for the likelihood of potential serious accidents. Calculations were performed to support conclusions where necessary.

Quantitative background parenchymal uptake on molecular breast imaging and breast cancer risk: a case-control study.

Science.gov (United States)

Hruska, Carrie B; Geske, Jennifer R; Swanson, Tiffinee N; Mammel, Alyssa N; Lake, David S; Manduca, Armando; Conners, Amy Lynn; Whaley, Dana H; Scott, Christopher G; Carter, Rickey E; Rhodes, Deborah J; O'Connor, Michael K; Vachon, Celine M

2018-06-05

Background parenchymal uptake (BPU), which refers to the level of Tc-99m sestamibi uptake within normal fibroglandular tissue on molecular breast imaging (MBI), has been identified as a breast cancer risk factor, independent of mammographic density. Prior analyses have used subjective categories to describe BPU. We evaluate a new quantitative method for assessing BPU by testing its reproducibility, comparing quantitative results with previously established subjective BPU categories, and determining the association of quantitative BPU with breast cancer risk. Two nonradiologist operators independently performed region-of-interest analysis on MBI images viewed in conjunction with corresponding digital mammograms. Quantitative BPU was defined as a unitless ratio of the average pixel intensity (counts/pixel) within the fibroglandular tissue versus the average pixel intensity in fat. Operator agreement and the correlation of quantitative BPU measures with subjective BPU categories assessed by expert radiologists were determined. Percent density on mammograms was estimated using Cumulus. The association of quantitative BPU with breast cancer (per one unit BPU) was examined within an established case-control study of 62 incident breast cancer cases and 177 matched controls. Quantitative BPU ranged from 0.4 to 3.2 across all subjects and was on average higher in cases compared to controls (1.4 versus 1.2, p Quantitative BPU was strongly correlated with subjective BPU categories (Spearman's r = 0.59 to 0.69, p quantitative BPU measure, assessed by intraclass correlation, was 0.92 and 0.98, respectively. Quantitative BPU measures showed either no correlation or weak negative correlation with mammographic percent density. In a model adjusted for body mass index and percent density, higher quantitative BPU was associated with increased risk of breast cancer for both operators (OR = 4.0, 95% confidence interval (CI) 1.6-10.1, and 2.4, 95% CI 1.2-4.7). Quantitative

Risk analysis of heat recovery steam generator with semi quantitative risk based inspection API 581

Science.gov (United States)

Prayogo, Galang Sandy; Haryadi, Gunawan Dwi; Ismail, Rifky; Kim, Seon Jin

2016-04-01

Corrosion is a major problem that most often occurs in the power plant. Heat recovery steam generator (HRSG) is an equipment that has a high risk to the power plant. The impact of corrosion damage causing HRSG power plant stops operating. Furthermore, it could be threaten the safety of employees. The Risk Based Inspection (RBI) guidelines by the American Petroleum Institute (API) 58 has been used to risk analysis in the HRSG 1. By using this methodology, the risk that caused by unexpected failure as a function of the probability and consequence of failure can be estimated. This paper presented a case study relating to the risk analysis in the HRSG, starting with a summary of the basic principles and procedures of risk assessment and applying corrosion RBI for process industries. The risk level of each HRSG equipment were analyzed: HP superheater has a medium high risk (4C), HP evaporator has a medium-high risk (4C), and the HP economizer has a medium risk (3C). The results of the risk assessment using semi-quantitative method of standard API 581 based on the existing equipment at medium risk. In the fact, there is no critical problem in the equipment components. Damage mechanisms were prominent throughout the equipment is thinning mechanism. The evaluation of the risk approach was done with the aim of reducing risk by optimizing the risk assessment activities.

Risk analysis of heat recovery steam generator with semi quantitative risk based inspection API 581

International Nuclear Information System (INIS)

Prayogo, Galang Sandy; Haryadi, Gunawan Dwi; Ismail, Rifky; Kim, Seon Jin

2016-01-01

Corrosion is a major problem that most often occurs in the power plant. Heat recovery steam generator (HRSG) is an equipment that has a high risk to the power plant. The impact of corrosion damage causing HRSG power plant stops operating. Furthermore, it could be threaten the safety of employees. The Risk Based Inspection (RBI) guidelines by the American Petroleum Institute (API) 58 has been used to risk analysis in the HRSG 1. By using this methodology, the risk that caused by unexpected failure as a function of the probability and consequence of failure can be estimated. This paper presented a case study relating to the risk analysis in the HRSG, starting with a summary of the basic principles and procedures of risk assessment and applying corrosion RBI for process industries. The risk level of each HRSG equipment were analyzed: HP superheater has a medium high risk (4C), HP evaporator has a medium-high risk (4C), and the HP economizer has a medium risk (3C). The results of the risk assessment using semi-quantitative method of standard API 581 based on the existing equipment at medium risk. In the fact, there is no critical problem in the equipment components. Damage mechanisms were prominent throughout the equipment is thinning mechanism. The evaluation of the risk approach was done with the aim of reducing risk by optimizing the risk assessment activities.

Risk analysis of heat recovery steam generator with semi quantitative risk based inspection API 581

Energy Technology Data Exchange (ETDEWEB)

Prayogo, Galang Sandy, E-mail: gasandylang@live.com; Haryadi, Gunawan Dwi; Ismail, Rifky [Department of Mechanical Engineering, Diponegoro University, Semarang (Indonesia); Kim, Seon Jin [Department of Mechanical & Automotive Engineering of Pukyong National University (Korea, Republic of)

2016-04-19

Corrosion is a major problem that most often occurs in the power plant. Heat recovery steam generator (HRSG) is an equipment that has a high risk to the power plant. The impact of corrosion damage causing HRSG power plant stops operating. Furthermore, it could be threaten the safety of employees. The Risk Based Inspection (RBI) guidelines by the American Petroleum Institute (API) 58 has been used to risk analysis in the HRSG 1. By using this methodology, the risk that caused by unexpected failure as a function of the probability and consequence of failure can be estimated. This paper presented a case study relating to the risk analysis in the HRSG, starting with a summary of the basic principles and procedures of risk assessment and applying corrosion RBI for process industries. The risk level of each HRSG equipment were analyzed: HP superheater has a medium high risk (4C), HP evaporator has a medium-high risk (4C), and the HP economizer has a medium risk (3C). The results of the risk assessment using semi-quantitative method of standard API 581 based on the existing equipment at medium risk. In the fact, there is no critical problem in the equipment components. Damage mechanisms were prominent throughout the equipment is thinning mechanism. The evaluation of the risk approach was done with the aim of reducing risk by optimizing the risk assessment activities.

Risk assessment in support of plant health

DEFF Research Database (Denmark)

Jeger, Michael; Schans, Jan; Lövei, Gabor L.

2012-01-01

environmental risk assessment and the evaluation of risk reducing options. Quantitative approaches have become increasingly important during this time. The Panel has developed such methods in climatic mapping (in association with the Joint Research Councils), application of spatial spread models, re......With the establishment of the Plant Health Panel in 2006, EFSA became the body responsible for risk assessment in the plant health area for the European Union (EU). Since then more than 70 outputs have been produced dealing with the full range of organisms harmful to plant health across all crop...... types and plants in the environment. There has been an increasing trend towards producing scientific opinions which are full pest risk assessments for the whole EU territory. In its work, and as a contribution to the wider development of risk assessment methodology, the Panel has developed a series...

Transport project evaluation: feasibility risk assessment and scenario forecasting

DEFF Research Database (Denmark)

Salling, Kim Bang; Leleur, Steen

2017-01-01

This paper presents a new approach to transport project assessment in terms of feasibility risk assessment and reference class forecasting. Conventionally, transport project assessment is based upon a Cost-Benefit Analysis (CBA) where evaluation criteria such as Benefit Cost Ratios (BCR...... on the preliminary construction cost estimates. Hereafter, a quantitative risk analysis is provided making use of Monte Carlo simulation. This approach facilitates random input parameters based upon reference class forecasting, hence, a parameter data fit has been performed in order to obtain validated probability...... Scenario Forecasting (RSF) frame. The RSF is anchored in the cost-benefit analysis; thus, it provides decision-makers with a quantitative mean of assessing the transport infrastructure project. First, the RSF method introduces uncertainties within the CBA by applying Optimism Bias uplifts...

Approaches to cancer assessment in EPA's Integrated Risk Information System.

Science.gov (United States)

Gehlhaus, Martin W; Gift, Jeffrey S; Hogan, Karen A; Kopylev, Leonid; Schlosser, Paul M; Kadry, Abdel-Razak

2011-07-15

The U.S. Environmental Protection Agency's (EPA) Integrated Risk Information System (IRIS) Program develops assessments of health effects that may result from chronic exposure to chemicals in the environment. The IRIS database contains more than 540 assessments. When supported by available data, IRIS assessments provide quantitative analyses of carcinogenic effects. Since publication of EPA's 2005 Guidelines for Carcinogen Risk Assessment, IRIS cancer assessments have implemented new approaches recommended in these guidelines and expanded the use of complex scientific methods to perform quantitative dose-response assessments. Two case studies of the application of the mode of action framework from the 2005 Cancer Guidelines are presented in this paper. The first is a case study of 1,2,3-trichloropropane, as an example of a chemical with a mutagenic mode of carcinogenic action thus warranting the application of age-dependent adjustment factors for early-life exposure; the second is a case study of ethylene glycol monobutyl ether, as an example of a chemical with a carcinogenic action consistent with a nonlinear extrapolation approach. The use of physiologically based pharmacokinetic (PBPK) modeling to quantify interindividual variability and account for human parameter uncertainty as part of a quantitative cancer assessment is illustrated using a case study involving probabilistic PBPK modeling for dichloromethane. We also discuss statistical issues in assessing trends and model fit for tumor dose-response data, analysis of the combined risk from multiple types of tumors, and application of life-table methods for using human data to derive cancer risk estimates. These issues reflect the complexity and challenges faced in assessing the carcinogenic risks from exposure to environmental chemicals, and provide a view of the current trends in IRIS carcinogenicity risk assessment. Copyright © 2011. Published by Elsevier Inc.

Approaches to cancer assessment in EPA's Integrated Risk Information System

International Nuclear Information System (INIS)

Gehlhaus, Martin W.; Gift, Jeffrey S.; Hogan, Karen A.; Kopylev, Leonid; Schlosser, Paul M.; Kadry, Abdel-Razak

2011-01-01

The U.S. Environmental Protection Agency's (EPA) Integrated Risk Information System (IRIS) Program develops assessments of health effects that may result from chronic exposure to chemicals in the environment. The IRIS database contains more than 540 assessments. When supported by available data, IRIS assessments provide quantitative analyses of carcinogenic effects. Since publication of EPA's 2005 Guidelines for Carcinogen Risk Assessment, IRIS cancer assessments have implemented new approaches recommended in these guidelines and expanded the use of complex scientific methods to perform quantitative dose-response assessments. Two case studies of the application of the mode of action framework from the 2005 Cancer Guidelines are presented in this paper. The first is a case study of 1,2,3-trichloropropane, as an example of a chemical with a mutagenic mode of carcinogenic action thus warranting the application of age-dependent adjustment factors for early-life exposure; the second is a case study of ethylene glycol monobutyl ether, as an example of a chemical with a carcinogenic action consistent with a nonlinear extrapolation approach. The use of physiologically based pharmacokinetic (PBPK) modeling to quantify interindividual variability and account for human parameter uncertainty as part of a quantitative cancer assessment is illustrated using a case study involving probabilistic PBPK modeling for dichloromethane. We also discuss statistical issues in assessing trends and model fit for tumor dose-response data, analysis of the combined risk from multiple types of tumors, and application of life-table methods for using human data to derive cancer risk estimates. These issues reflect the complexity and challenges faced in assessing the carcinogenic risks from exposure to environmental chemicals, and provide a view of the current trends in IRIS carcinogenicity risk assessment.

Quantitative prediction of oral cancer risk in patients with oral leukoplakia.

Science.gov (United States)

Liu, Yao; Li, Yicheng; Fu, Yue; Liu, Tong; Liu, Xiaoyong; Zhang, Xinyan; Fu, Jie; Guan, Xiaobing; Chen, Tong; Chen, Xiaoxin; Sun, Zheng

2017-07-11

Exfoliative cytology has been widely used for early diagnosis of oral squamous cell carcinoma. We have developed an oral cancer risk index using DNA index value to quantitatively assess cancer risk in patients with oral leukoplakia, but with limited success. In order to improve the performance of the risk index, we collected exfoliative cytology, histopathology, and clinical follow-up data from two independent cohorts of normal, leukoplakia and cancer subjects (training set and validation set). Peaks were defined on the basis of first derivatives with positives, and modern machine learning techniques were utilized to build statistical prediction models on the reconstructed data. Random forest was found to be the best model with high sensitivity (100%) and specificity (99.2%). Using the Peaks-Random Forest model, we constructed an index (OCRI2) as a quantitative measurement of cancer risk. Among 11 leukoplakia patients with an OCRI2 over 0.5, 4 (36.4%) developed cancer during follow-up (23 ± 20 months), whereas 3 (5.3%) of 57 leukoplakia patients with an OCRI2 less than 0.5 developed cancer (32 ± 31 months). OCRI2 is better than other methods in predicting oral squamous cell carcinoma during follow-up. In conclusion, we have developed an exfoliative cytology-based method for quantitative prediction of cancer risk in patients with oral leukoplakia.

Systems Toxicology: From Basic Research to Risk Assessment

Science.gov (United States)

2014-01-01

Systems Toxicology is the integration of classical toxicology with quantitative analysis of large networks of molecular and functional changes occurring across multiple levels of biological organization. Society demands increasingly close scrutiny of the potential health risks associated with exposure to chemicals present in our everyday life, leading to an increasing need for more predictive and accurate risk-assessment approaches. Developing such approaches requires a detailed mechanistic understanding of the ways in which xenobiotic substances perturb biological systems and lead to adverse outcomes. Thus, Systems Toxicology approaches offer modern strategies for gaining such mechanistic knowledge by combining advanced analytical and computational tools. Furthermore, Systems Toxicology is a means for the identification and application of biomarkers for improved safety assessments. In Systems Toxicology, quantitative systems-wide molecular changes in the context of an exposure are measured, and a causal chain of molecular events linking exposures with adverse outcomes (i.e., functional and apical end points) is deciphered. Mathematical models are then built to describe these processes in a quantitative manner. The integrated data analysis leads to the identification of how biological networks are perturbed by the exposure and enables the development of predictive mathematical models of toxicological processes. This perspective integrates current knowledge regarding bioanalytical approaches, computational analysis, and the potential for improved risk assessment. PMID:24446777

Risk assessment for biodiversity conservation planning in Pacific Northwest forests

Science.gov (United States)

Becky K. Kerns; Alan Ager

2007-01-01

Risk assessment can provide a robust strategy for landscape-scale planning challenges associated with species conservation and habitat protection in Pacific Northwest forests. We provide an overview of quantitative and probabilistic ecological risk assessment with focus on the application of approaches and influences from the actuarial, financial, and technical...

Risk assessment of safety violations for coal mines

Energy Technology Data Exchange (ETDEWEB)

Megan Orsulaka; Vladislav Kecojevicb; Larry Graysona; Antonio Nietoa [Pennsylvania State University, University Park, PA (United States). Dept of Energy and Mineral Engineering

2010-09-15

This article presents an application of a risk assessment approach in characterising the risks associated with safety violations in underground bituminous mines in Pennsylvania using the Mine Safety and Health Administration (MSHA) citation database. The MSHA database on citations provides an opportunity to assess risks in mines through scrutiny of violations of mandatory safety standards. In this study, quantitative risk assessment is performed, which allows determination of the frequency of occurrence of safety violations (through associated citations) as well as the consequences of them in terms of penalty assessments. Focus is on establishing risk matrices on citation experiences of mines, which can give early indication of emerging potentially serious problems. The resulting frequency, consequence and risk rankings present valuable tools for prioritising resource allocations, determining control strategies, and could potentially contribute to more proactive prevention of incidents and injuries.

Quantitative, Qualitative and Geospatial Methods to Characterize HIV Risk Environments.

Directory of Open Access Journals (Sweden)

Erin E Conners

Full Text Available Increasingly, 'place', including physical and geographical characteristics as well as social meanings, is recognized as an important factor driving individual and community health risks. This is especially true among marginalized populations in low and middle income countries (LMIC, whose environments may also be more difficult to study using traditional methods. In the NIH-funded longitudinal study Mapa de Salud, we employed a novel approach to exploring the risk environment of female sex workers (FSWs in two Mexico/U.S. border cities, Tijuana and Ciudad Juárez. In this paper we describe the development, implementation, and feasibility of a mix of quantitative and qualitative tools used to capture the HIV risk environments of FSWs in an LMIC setting. The methods were: 1 Participatory mapping; 2 Quantitative interviews; 3 Sex work venue field observation; 4 Time-location-activity diaries; 5 In-depth interviews about daily activity spaces. We found that the mixed-methodology outlined was both feasible to implement and acceptable to participants. These methods can generate geospatial data to assess the role of the environment on drug and sexual risk behaviors among high risk populations. Additionally, the adaptation of existing methods for marginalized populations in resource constrained contexts provides new opportunities for informing public health interventions.

Quantitative flood risk assessment for Polders

International Nuclear Information System (INIS)

Manen, Sipke E. van; Brinkhuis, Martine

2005-01-01

In the Netherlands, the design of dikes and other water retaining structures is based on an acceptable probability (frequency) of overtopping. In 1993 a new safety concept was introduced based on total flood risk. Risk was defined as the product of probability and consequences. In recent years advanced tools have become available to calculate the actual flood risk of a polder. This paper describes the application of these tools to an existing lowland river area. The complete chain of calculations necessary to estimate the risk of flooding of a polder (or dike ring) is presented. The difficulties in applying the present day tools and the largest uncertainties in the calculations are shown

Quantitative flood risk assessment for Polders

Energy Technology Data Exchange (ETDEWEB)

Manen, Sipke E. van [Ministry of Transport, Public Works and Water Management, Bouwdienst Rijkswaterstaat, Griffioenlaan 2, Utrecht 3526 (Netherlands)]. E-mail: s.e.vmanen@bwd.rws.minvenw.nl; Brinkhuis, Martine [Ministry of Transport, Public Works and Water Management, Delft (Netherlands)

2005-12-01

In the Netherlands, the design of dikes and other water retaining structures is based on an acceptable probability (frequency) of overtopping. In 1993 a new safety concept was introduced based on total flood risk. Risk was defined as the product of probability and consequences. In recent years advanced tools have become available to calculate the actual flood risk of a polder. This paper describes the application of these tools to an existing lowland river area. The complete chain of calculations necessary to estimate the risk of flooding of a polder (or dike ring) is presented. The difficulties in applying the present day tools and the largest uncertainties in the calculations are shown.

Potential impacts of radon, terrestrial gamma and cosmic rays on childhood leukemia in France: a quantitative risk assessment

Energy Technology Data Exchange (ETDEWEB)

Laurent, Olivier [French Institute for Radiological Protection and Nuclear Safety, Radiobiology and Epidemiology Department, IRSN, PRP-HOM, SRBE, LEPID, Fontenay aux Roses (France); University of California, Irvine, Department of Population Health and Disease Prevention, Irvine, CA (United States); Ancelet, Sophie; Laurier, Dominique [French Institute for Radiological Protection and Nuclear Safety, Radiobiology and Epidemiology Department, IRSN, PRP-HOM, SRBE, LEPID, Fontenay aux Roses (France); Richardson, David B. [University of North Carolina at Chapel Hill, Department of Epidemiology, School of Public Health, Chapel Hill, NC (United States); Hemon, Denis; Demoury, Claire; Clavel, Jacqueline [Inserm, CESP Center for Research in Epidemiology and Population Health, U1018, Environmental Epidemiology of Cancer Team, Villejuif (France); Paris-Sud University, UMRS 1018, Villejuif (France); Ielsch, Geraldine [French Institute for Radiological Protection and Nuclear Safety, Assessment Unit for Risks Related to Natural Radioactivity, IRSN, PRP-DGE, SEDRAN, BRN, Fontenay aux Roses (France)

2013-05-15

Previous epidemiological studies and quantitative risk assessments (QRA) have suggested that natural background radiation may be a cause of childhood leukemia. The present work uses a QRA approach to predict the excess risk of childhood leukemia in France related to three components of natural radiation: radon, cosmic rays and terrestrial gamma rays, using excess relative and absolute risk models proposed by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Both models were developed from the Life Span Study (LSS) of Japanese A-bomb survivors. Previous risk assessments were extended by considering uncertainties in radiation-related leukemia risk model parameters as part of this process, within a Bayesian framework. Estimated red bone marrow doses cumulated during childhood by the average French child due to radon, terrestrial gamma and cosmic rays are 4.4, 7.5 and 4.3 mSv, respectively. The excess fractions of cases (expressed as percentages) associated with these sources of natural radiation are 20 % [95 % credible interval (CI) 0-68 %] and 4 % (95 % CI 0-11 %) under the excess relative and excess absolute risk models, respectively. The large CIs, as well as the different point estimates obtained under these two models, highlight the uncertainties in predictions of radiation-related childhood leukemia risks. These results are only valid provided that models developed from the LSS can be transferred to the population of French children and to chronic natural radiation exposures, and must be considered in view of the currently limited knowledge concerning other potential risk factors for childhood leukemia. Last, they emphasize the need for further epidemiological investigations of the effects of natural radiation on childhood leukemia to reduce uncertainties and help refine radiation protection standards. (orig.)

Potential impacts of radon, terrestrial gamma and cosmic rays on childhood leukemia in France: a quantitative risk assessment

International Nuclear Information System (INIS)

Laurent, Olivier; Ancelet, Sophie; Laurier, Dominique; Richardson, David B.; Hemon, Denis; Demoury, Claire; Clavel, Jacqueline; Ielsch, Geraldine

2013-01-01

Previous epidemiological studies and quantitative risk assessments (QRA) have suggested that natural background radiation may be a cause of childhood leukemia. The present work uses a QRA approach to predict the excess risk of childhood leukemia in France related to three components of natural radiation: radon, cosmic rays and terrestrial gamma rays, using excess relative and absolute risk models proposed by the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR). Both models were developed from the Life Span Study (LSS) of Japanese A-bomb survivors. Previous risk assessments were extended by considering uncertainties in radiation-related leukemia risk model parameters as part of this process, within a Bayesian framework. Estimated red bone marrow doses cumulated during childhood by the average French child due to radon, terrestrial gamma and cosmic rays are 4.4, 7.5 and 4.3 mSv, respectively. The excess fractions of cases (expressed as percentages) associated with these sources of natural radiation are 20 % [95 % credible interval (CI) 0-68 %] and 4 % (95 % CI 0-11 %) under the excess relative and excess absolute risk models, respectively. The large CIs, as well as the different point estimates obtained under these two models, highlight the uncertainties in predictions of radiation-related childhood leukemia risks. These results are only valid provided that models developed from the LSS can be transferred to the population of French children and to chronic natural radiation exposures, and must be considered in view of the currently limited knowledge concerning other potential risk factors for childhood leukemia. Last, they emphasize the need for further epidemiological investigations of the effects of natural radiation on childhood leukemia to reduce uncertainties and help refine radiation protection standards. (orig.)

A Quantitative Risk Assessment Model Involving Frequency and Threat Degree under Line-of-Business Services for Infrastructure of Emerging Sensor Networks.

Science.gov (United States)

Jing, Xu; Hu, Hanwen; Yang, Huijun; Au, Man Ho; Li, Shuqin; Xiong, Naixue; Imran, Muhammad; Vasilakos, Athanasios V

2017-03-21

The prospect of Line-of-Business Services (LoBSs) for infrastructure of Emerging Sensor Networks (ESNs) is exciting. Access control remains a top challenge in this scenario as the service provider's server contains a lot of valuable resources. LoBSs' users are very diverse as they may come from a wide range of locations with vastly different characteristics. Cost of joining could be low and in many cases, intruders are eligible users conducting malicious actions. As a result, user access should be adjusted dynamically. Assessing LoBSs' risk dynamically based on both frequency and threat degree of malicious operations is therefore necessary. In this paper, we proposed a Quantitative Risk Assessment Model (QRAM) involving frequency and threat degree based on value at risk. To quantify the threat degree as an elementary intrusion effort, we amend the influence coefficient of risk indexes in the network security situation assessment model. To quantify threat frequency as intrusion trace effort, we make use of multiple behavior information fusion. Under the influence of intrusion trace, we adapt the historical simulation method of value at risk to dynamically access LoBSs' risk. Simulation based on existing data is used to select appropriate parameters for QRAM. Our simulation results show that the duration influence on elementary intrusion effort is reasonable when the normalized parameter is 1000. Likewise, the time window of intrusion trace and the weight between objective risk and subjective risk can be set to 10 s and 0.5, respectively. While our focus is to develop QRAM for assessing the risk of LoBSs for infrastructure of ESNs dynamically involving frequency and threat degree, we believe it is also appropriate for other scenarios in cloud computing.

A Quantitative Risk Assessment Model Involving Frequency and Threat Degree under Line-of-Business Services for Infrastructure of Emerging Sensor Networks

Science.gov (United States)

Jing, Xu; Hu, Hanwen; Yang, Huijun; Au, Man Ho; Li, Shuqin; Xiong, Naixue; Imran, Muhammad; Vasilakos, Athanasios V.

2017-01-01

The prospect of Line-of-Business Services (LoBSs) for infrastructure of Emerging Sensor Networks (ESNs) is exciting. Access control remains a top challenge in this scenario as the service provider’s server contains a lot of valuable resources. LoBSs’ users are very diverse as they may come from a wide range of locations with vastly different characteristics. Cost of joining could be low and in many cases, intruders are eligible users conducting malicious actions. As a result, user access should be adjusted dynamically. Assessing LoBSs’ risk dynamically based on both frequency and threat degree of malicious operations is therefore necessary. In this paper, we proposed a Quantitative Risk Assessment Model (QRAM) involving frequency and threat degree based on value at risk. To quantify the threat degree as an elementary intrusion effort, we amend the influence coefficient of risk indexes in the network security situation assessment model. To quantify threat frequency as intrusion trace effort, we make use of multiple behavior information fusion. Under the influence of intrusion trace, we adapt the historical simulation method of value at risk to dynamically access LoBSs’ risk. Simulation based on existing data is used to select appropriate parameters for QRAM. Our simulation results show that the duration influence on elementary intrusion effort is reasonable when the normalized parameter is 1000. Likewise, the time window of intrusion trace and the weight between objective risk and subjective risk can be set to 10 s and 0.5, respectively. While our focus is to develop QRAM for assessing the risk of LoBSs for infrastructure of ESNs dynamically involving frequency and threat degree, we believe it is also appropriate for other scenarios in cloud computing. PMID:28335569

78 FR 23901 - Interagency Risk Assessment-Listeria monocytogenes

Science.gov (United States)

2013-04-23

... discrimination in all its programs and activities on the basis of race, color, national origin, gender, religion....'' The purpose of this draft quantitative risk assessment (QRA) is to evaluate the public health impact... retail food store and examines how that risk may be impacted by changes to common or recommended...

Current status and future expectation concerning probabilistic risk assessment of NPPs. 1. Features and issues of probabilistic risk assessment methodology

International Nuclear Information System (INIS)

Yamashita, Masahiro

2012-01-01

Probabilistic risk assessment (PRA) of Nuclear Power Plants (NPPs) could play an important role in assuring safety of NPPs. However PRA had not always effectively used, which was indicated in Japanese government's report on Fukushima Daiichi NPP accident. At the Risk Technical Committee (RTC) of Standards Committee of Atomic Energy Society of Japan, preparation of standards (implementing criteria) focusing on PRA methodology and investigation on basic philosophy for use of PRA had been in progress. Based on activities of RTC, a serial in three articles including this described current status and future expectation concerning probabilistic risk assessment of NPPs. This article introduced features and issues of PRA methodology related to the use of PRA. Features of PRA methodology could be shown as (1) systematic and comprehensive understanding of risk, (2) support of grading approach, (3) identification of effective safety upgrade measures and (4) quantitative understanding of effects of uncertainty. Issues of PRA methodology were (1) extension of PRA application area, (2) upgrade of PRA methodology, (3) quality assurance of PRA, (4) treatment of uncertainty and (5) quantitative evaluation criteria. (T. Tanaka)

Information Risk Management: Qualitative or Quantitative? Cross industry lessons from medical and financial fields

Directory of Open Access Journals (Sweden)

Upasna Saluja

2012-06-01

Full Text Available Enterprises across the world are taking a hard look at their risk management practices. A number of qualitative and quantitative models and approaches are employed by risk practitioners to keep risk under check. As a norm most organizations end up choosing the more flexible, easier to deploy and customize qualitative models of risk assessment. In practice one sees that such models often call upon the practitioners to make qualitative judgments on a relative rating scale which brings in considerable room for errors, biases and subjectivity. On the other hand under the quantitative risk analysis approach, estimation of risk is connected with application of numerical measures of some kind. Medical risk management models lend themselves as ideal candidates for deriving lessons for Information Security Risk Management. We can use this considerably developed understanding of risk management from the medical field especially Survival Analysis towards handling risks that information infrastructures face. Similarly, financial risk management discipline prides itself on perhaps the most quantifiable of models in risk management. Market Risk and Credit Risk Information Security Risk Management can make risk measurement more objective and quantitative by referring to the approach of Credit Risk. During the recent financial crisis many investors and financial institutions lost money or went bankrupt respectively, because they did not apply the basic principles of risk management. Learning from the financial crisis provides some valuable lessons for information risk management.

Semi-Quantitative Assessment of the Health Risk of Occupational Exposure to Chemicals and Evaluation of Spirometry Indices on the Staff of Petrochemical Industry

Directory of Open Access Journals (Sweden)

Hajar Dazi

2017-01-01

Full Text Available Background & Aims of the Study: Petrochemical industry is an important industry in the economic development of the country that causes employees have exposure with several kinds of contamination. The aim of this study was Semi-quantitative assessment of the health risk of occupational exposure to chemical materials and investigation of spirometry indices between employees of petrochemical industry. Material & Methods: This cross-sectional study was conducted in one of the petrochemical industry complex in a special area of Assaluyeh in Iran in 2016. Health risk assessment of exposure to harmful chemical agents was performed in all of units and during three stages (identification of harmful material, determination of hazard rate of the chemical material, exposure rate and estimate of risk rate. Spirometry indices were measured using spirometry. Results: The results of chemical materials risk assessment showed that Raffinate in Butadiene unit has identified the highest amount of risk rank among 27 chemical materials in investigated units. In comparison with spirometry indices in Olefine unit between age with FVC parameter and history work with FVC and FEV1 parameters has observed a significant and negative correlation (P<0.05. Conclusion: The results of risk assessment in all of the petrochemical units showed that 48.14% of materials were at low risk level, 29.62% medium risk, 18.51% high risk and 3.7% had very high risk level. The variables affecting on spirometry employees such as age and work experience play an important role in reducing the pulmonary function tests in exposed subjects.

Quantitative influence of risk factors on blood glucose level.

Science.gov (United States)

Chen, Songjing; Luo, Senlin; Pan, Limin; Zhang, Tiemei; Han, Longfei; Zhao, Haixiu

2014-01-01

The aim of this study is to quantitatively analyze the influence of risk factors on the blood glucose level, and to provide theory basis for understanding the characteristics of blood glucose change and confirming the intervention index for type 2 diabetes. The quantitative method is proposed to analyze the influence of risk factors on blood glucose using back propagation (BP) neural network. Ten risk factors are screened first. Then the cohort is divided into nine groups by gender and age. According to the minimum error principle, nine BP models are trained respectively. The quantitative values of the influence of different risk factors on the blood glucose change can be obtained by sensitivity calculation. The experiment results indicate that weight is the leading cause of blood glucose change (0.2449). The second factors are cholesterol, age and triglyceride. The total ratio of these four factors reaches to 77% of the nine screened risk factors. And the sensitivity sequences can provide judgment method for individual intervention. This method can be applied to risk factors quantitative analysis of other diseases and potentially used for clinical practitioners to identify high risk populations for type 2 diabetes as well as other disease.

The profile of quantitative risk indicators in Krsko NPP

International Nuclear Information System (INIS)

Vrbanic, I.; Basic, I.; Bilic-Zabric, T.; Spiler, J.

2004-01-01

During the past decade strong initiative was observed which was aimed at incorporating information on risk into various aspects of operation of nuclear power plants. The initiative was observable in activities carried out by regulators as well as utilities and industry. It resulted in establishing the process, or procedure, which is often referred to as integrated decision making or risk informed decision making. In this process, engineering analyses and evaluations that are usually termed traditional and that rely on considerations of safety margins and defense in depth are supplemented by quantitative indicators of risk. Throughout the process, the plant risk was most commonly expressed in terms of likelihood of events involving damage to the reactor core and events with radiological releases to the environment. These became two commonly used quantitative indicators or metrics of plant risk (or, reciprocally, plant safety). They were evaluated for their magnitude (e.g. the expected number of events per specified time interval), as well as their profile (e.g. the types of contributing events). The information for quantitative risk indicators (to be used in risk informing process) is obtained from plant's probabilistic safety analyses or analyses of hazards. It is dependable on issues such as availability of input data or quality of model or analysis. Nuclear power plant Krsko has recently performed Periodic Safety Review, which was a good opportunity to evaluate and integrate the plant specific information on quantitative plant risk indicators and their profile. The paper discusses some aspects of quantitative plant risk profile and its perception.(author)

Risk indices in comparative risk assessment studies

International Nuclear Information System (INIS)

Hubert, P.

1984-01-01

More than a decade ago the development of comparative risk assessment studies aroused overwhelming interest. There was no doubt that data on the health and safety aspects of energy systems would greatly benefit, or even end, the debate on nuclear energy. Although such attempts are still strongly supported, the rose-coloured expectations of the early days have faded. The high uncertainties, and the contradictory aspect, of the first results might explain this evolution. The loose connection between the range of computed risk indices and the questions on which the debate was focused is another reason for this decline in interest. Important research work is being carried out aiming at reducing the different kinds of uncertainties. Rather than the uncertainties, the paper considers the meaning of available risk indices and proposes more significant indices with respect to the goals of risk assessment. First, the indices which are of frequent use in comparative studies are listed. The stress is put on a French comparative study from which most examples are drawn. Secondly, the increase in magnitude of the indices and the decrease in the attributability of the risk to a given system is shown to be a consequence of the trend towards more comprehensive analyses. Thirdly, the ambiguity of such indices as the collective occupational risk is underlined, and a possible solution is suggested. Whenever risk assessments are related to pragmatic decision making problems it is possible to find satisfactory risk indices. The development of cost-effectiveness analyses and the proposals for quantitative safety goals clearly demonstrate this point. In the field of comparison of social impacts some proposals are made, but there remain some gaps still to be filled. (author)

Research on risk assessment for maritime transport of radioactive materials. Preparation of maritime accident data for risk assessment

International Nuclear Information System (INIS)

Odano, Naoteru; Sawada, Ken-ichi; Mochiduki, Hiromitsu; Hirao, Yoshihiro; Asami, Mitsufumi

2010-01-01

Maritime transport of radioactive materials has been playing an important role in the nuclear fuel cycle in Japan. Due to recent increase of transported radioactive materials and diversification of transport packages with enlargement of nuclear research, development and utilization, safety securement for maritime transport of radioactive materials is one of important issues in the nuclear fuel cycle. Based squarely on the current circumstances, this paper summarizes discussion on importance of utilization of results of risk assessment for maritime transport of radioactive materials. A plan for development of comprehensive methodology to assess risks in maritime transport of radioactive materials is also described. Preparations of database of maritime accident to be necessary for risk assessment are also summarized. The prepared data could be utilized for future quantitative risk assessment, such as the event trees and fault trees analyses, for maritime transport of radioactive materials. The frequency of severe accident that the package might be damaged is also estimated using prepared data. (author)

Multi-attribute risk assessment for risk ranking of natural gas pipelines

International Nuclear Information System (INIS)

Brito, A.J.; Almeida, A.T. de

2009-01-01

The paper presents a decision model for risk assessment and for risk ranking of sections of natural gas pipelines based on multi-attribute utility theory. Pipeline hazard scenarios are surveyed and the reasons for a risk assessment model based on a multi-attribute approach are presented. Three dimensions of impact and the need to translate decision-makers' preferences into risk management decisions are highlighted. The model approaches these factors by using a multi-attribute utility function, in order to produce multi-dimensional risk measurements. By using decision analysis concepts, this model quantitatively incorporates the decision-maker's preferences and behavior regarding risk within clear and consistent risk measurements. In order to support the prioritizing of critical sections of pipeline in natural gas companies, this multi-attribute model also allows sections of pipeline to be ranked into a risk hierarchy. A numerical application based on a real case study was undertaken so that the effectiveness of the decision model could be verified

Microbial aerosol generation during laboratory accidents and subsequent risk assessment.

Science.gov (United States)

Bennett, A; Parks, S

2006-04-01

To quantify microbial aerosols generated by a series of laboratory accidents and to use these data in risk assessment. A series of laboratory accident scenarios have been devised and the microbial aerosol generated by them has been measured using a range of microbial air samplers. The accident scenarios generating the highest aerosol concentrations were, dropping a fungal plate, dropping a large bottle, centrifuge rotor leaks and a blocked syringe filter. Many of these accidents generated low particle size aerosols, which would be inhaled into the lungs of any exposed laboratory staff. Spray factors (SFs) have been calculated using the results of these experiments as an indicator of the potential for accidents to generate microbial aerosols. Model risk assessments have been described using the SF data. Quantitative risk assessment of laboratory accidents can provide data that can aid the design of containment laboratories and the response to laboratory accidents. A methodology has been described and supporting data provided to allow microbiological safety officers to carry out quantitative risk assessment of laboratory accidents.

Engineering aspects of probabilistic risk assessment

International Nuclear Information System (INIS)

vonHerrmann, J.L.; Wood, P.J.

1984-01-01

Over the last decade, the use of probabilistic risk assessment (PRA) in the nuclear industry has expanded significantly. In these analyses the probabilities of experiencing certain undesired events (for example, a plant accident which results in damage to the nuclear fuel) are estimated and the consequences of these events are evaluated in terms of some common measure. These probabilities and consequences are then combined to form a representation of the risk associated with the plant studied. In the relatively short history of probabilistic risk assessment of nuclear power plants, the primary motivation for these studies has been the quantitative assessment of public risk associated with a single plant or group of plants. Accordingly, the primary product of most PRAs performed to date has been a 'risk curve' in which the probability (or expected frequency) of exceeding a certain consequence level is plotted against that consequence. The most common goal of these assessments has been to demonstrate the 'acceptability' of the calculated risk by comparison of the resultant risk curve to risk curves associated with other plants or with other societal risks. Presented here are brief descriptions of some alternate applications of PRAs, a discussion of how these other applications compare or contrast with the currently popular uses of PRA, and a discussion of the relative benefits of each

Microbiological risk assessment for personal care products.

Science.gov (United States)

Stewart, S E; Parker, M D; Amézquita, A; Pitt, T L

2016-12-01

qualitative or semi-quantitative rather than fully quantitative risk assessment, but an added benefit is that the disciplined structuring of available knowledge enables clear identification of gaps to target resources and if appropriate, instigate data generation. © 2016 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

Quantitative assessment of breast density from digitized mammograms into Tabar's patterns

Energy Technology Data Exchange (ETDEWEB)

Jamal, N [Medical Technology Division, Malaysian Institute for Nuclear Technology Research (MINT) 43000 Kajang (Malaysia); Ng, K-H [Department of Radiology, University of Malaya, 50603 Kuala Lumpur (Malaysia); Looi, L-M [Department of Pathology, University of Malaya, 50603 Kuala Lumpur (Malaysia); McLean, D [Medical Physics Department, Westmead Hospital, Sydney, NSW 2145 (Australia); Zulfiqar, A [Department of Radiology, Hospital Universiti Kebangsaan Malaysia, 56000 Malaysia, Kuala Lumpur, Malaysia (Malaysia); Tan, S-P [Department of Radiology, Hospital Universiti Kebangsaan Malaysia, 56000 Malaysia, Kuala Lumpur, Malaysia (Malaysia); Liew, W-F [Department of Radiology, Hospital Universiti Kebangsaan Malaysia, 56000 Malaysia, Kuala Lumpur, Malaysia (Malaysia); Shantini, A [Department of Radiology, Kuala Lumpur Hospital, 50586 Kuala Lumpur (Malaysia); Ranganathan, S [Department of Radiology, University of Malaya, 50603 Kuala Lumpur (Malaysia)

2006-11-21

We describe a semi-automated technique for the quantitative assessment of breast density from digitized mammograms in comparison with patterns suggested by Tabar. It was developed using the MATLAB-based graphical user interface applications. It is based on an interactive thresholding method, after a short automated method that shows the fibroglandular tissue area, breast area and breast density each time new thresholds are placed on the image. The breast density is taken as a percentage of the fibroglandular tissue to the breast tissue areas. It was tested in four different ways, namely by examining: (i) correlation of the quantitative assessment results with subjective classification, (ii) classification performance using the quantitative assessment technique, (iii) interobserver agreement and (iv) intraobserver agreement. The results of the quantitative assessment correlated well (r{sup 2} = 0.92) with the subjective Tabar patterns classified by the radiologist (correctly classified 83% of digitized mammograms). The average kappa coefficient for the agreement between the readers was 0.63. This indicated moderate agreement between the three observers in classifying breast density using the quantitative assessment technique. The kappa coefficient of 0.75 for intraobserver agreement reflected good agreement between two sets of readings. The technique may be useful as a supplement to the radiologist's assessment in classifying mammograms into Tabar's pattern associated with breast cancer risk.

Quantitative Risk Assessment (QRA) for an Underground Blowout Scenario in the Gulf of Mexico (GoM) Well

Science.gov (United States)

Tyagi, M.; Zulqarnain, M.

2017-12-01

Offshore oil and gas exploration and production operations, involve the use of some of the cutting edge and challenging technologies of the modern time. These technological complex operations involves the risk of major accidents as well, which have been demonstrated by disasters such as the explosion and fire on the UK production platform piper alpha, the Canadian semi-submersible drilling rig Ocean Ranger and the explosion and capsizing of Deepwater horizon rig in the Gulf of Mexico. By conducting Quantitative Risk Assessment (QRA), safety of various operations as well as their associated risks and significance during the entire life phase of an offshore project can be quantitatively estimated. In an underground blowout, the uncontrolled formation fluids from higher pressure formation may charge up shallower overlying low pressure formations or may migrate to sea floor. Consequences of such underground blowouts range from no visible damage at the surface to the complete loss of well, loss of drilling rig, seafloor subsidence or hydrocarbons discharged to the environment. These blowouts might go unnoticed until the over pressured sands, which are the result of charging from higher pressure reservoir due to an underground blowout. Further, engineering formulas used to estimate the fault permeability and thickness are very simple in nature and may add to uncertainty in the estimated parameters. In this study the potential of a deepwater underground blowout are assessed during drilling life phase of a well in Popeye-Genesis field reservoir in the Gulf of Mexico to estimate the time taken to charge a shallower zone to its leak-off test (LOT) value. Parametric simulation results for selected field case show that for relatively high permeability (k = 40mD) fault connecting a deep over-pressured zone to a shallower low-pressure zone of similar reservoir volumes, the time to recharge the shallower zone up to its threshold LOT value is about 135 years. If the ratio of the

Information Risk Management: Qualitative or Quantitative? Cross industry lessons from medical and financial fields

OpenAIRE

Upasna Saluja; Norbik Bashah Idris

2012-01-01

Enterprises across the world are taking a hard look at their risk management practices. A number of qualitative and quantitative models and approaches are employed by risk practitioners to keep risk under check. As a norm most organizations end up choosing the more flexible, easier to deploy and customize qualitative models of risk assessment. In practice one sees that such models often call upon the practitioners to make qualitative judgments on a relative rating scale which brings in consid...

Food Safety Management in a Global Environment: The Role of Risk Assessment Models

OpenAIRE

Fuentes-Pila, Joaquin; Jimeno, Vicente; Manzano, Amparo; Rodriguez Monroy, Carlos; Mar Fernandez, Maria Del

2006-01-01

Quantitative risk assessment models are playing a minor role in the development of the new EU legal framework for food safety. There is a tendency of the EU institutions to apply the precautionary principle versus the predisposition of the USA institutions to rely on risk analysis. This paper provides a comparison of the role played by quantitative risk assessment models in the development of new policies on food safety in the EU and in the USA, focusing on a study case: the supply chain of s...

Contract farming risks: A quantitative assessment

Directory of Open Access Journals (Sweden)

Arkins M Kabungo

2016-03-01

Full Text Available The objective of this study is to identify the key risks facing each of the stakeholders in the export-focused paprika value chain in Zambia. Although a deterministic cost-benefit analysis indicated that this outgrower scheme would have a very satisfactory net present value (NPV, a Monte Carlo analysis using an integrated financial–economic–stakeholder model identifies a number of risk variables that could make this system unsustainable. The major risks include the variability of the real exchange rate in Zambia; the international price of paprika; and the farm yield rates. This analysis points out that irrigation systems are very important for both stabilising and increasing yields. The analysis also shows the limitations of loan financing for such outgrower arrangements when at the sector level it is difficult or even impossible to mitigate the risks from real exchange rate movements and changes in international commodity prices. This micro-level analysis shows how critical real exchange rate management policies are in achieving sustainability of such export-oriented value chains.

Advancing Risk Assessment through the Application of Systems Toxicology

Science.gov (United States)

Sauer, John Michael; Kleensang, André; Peitsch, Manuel C.; Hayes, A. Wallace

2016-01-01

Risk assessment is the process of quantifying the probability of a harmful effect to individuals or populations from human activities. Mechanistic approaches to risk assessment have been generally referred to as systems toxicology. Systems toxicology makes use of advanced analytical and computational tools to integrate classical toxicology and quantitative analysis of large networks of molecular and functional changes occurring across multiple levels of biological organization. Three presentations including two case studies involving both in vitro and in vivo approaches described the current state of systems toxicology and the potential for its future application in chemical risk assessment. PMID:26977253

A study on framework for assessing limiting condition for operation(LCOs) quantitatively in a CANDU reactor

International Nuclear Information System (INIS)

Kang, Kyung Min

2003-02-01

Limiting conditions for operations define the allowed outage times and the actions to be taken if the repair cannot be completed within the AOT. Typically the actions required are plant shutdown. In situations where the risk associated with the action, i.e., the risk of plant shutdown given a failure in the safety system, may be substantial, a strategy is needed to control the risk implications. In this study the strategy is evaluated quantitatively using a tool of system dynamics. The strategic actions associated with LCO needs to be assessed dynamically. System dynamics technique is easy enough to be applied for quantitative assessment of LCO, where the system dynamics is an important factor in evaluating operational modes of nuclear power plants. The review on the improvements of overly conservative technical specification has been performed in this study. The VENSIM tool has been applied to evaluate quantitatively the LCO of the auxiliary feed water systems in the Wol-Sung nuclear power plant. A value of core damage frequency in PSA is used as risk measure. The analysis of both full power operation and shutdown operation has been compared for the value of the CDF. This study shows a plot of LCO full power operating and shutdown risks in term of core damage probability for failure of AFWS (auxiliary feedwater system). Obtaining a lower risk level in a stable mode, compared to the LCO operation alternative, is the principal motivation of going to full power operational mode or shutdown operational mode. A time dependent framework developed in this study has been applied to assess the LCO of the example problem and it is shown that it is very flexible in that it can be applied to assess LCO quantitatively under any operational context of the technical specifications. This study contributes risk informed regulation to enhance and optimize the LCO of previous technical specifications for CANDU through developing framework in application proposed in this methodology

Accuracy of quantitative visual soil assessment

Science.gov (United States)

van Leeuwen, Maricke; Heuvelink, Gerard; Stoorvogel, Jetse; Wallinga, Jakob; de Boer, Imke; van Dam, Jos; van Essen, Everhard; Moolenaar, Simon; Verhoeven, Frank; Stoof, Cathelijne

2016-04-01

Visual soil assessment (VSA) is a method to assess soil quality visually, when standing in the field. VSA is increasingly used by farmers, farm organisations and companies, because it is rapid and cost-effective, and because looking at soil provides understanding about soil functioning. Often VSA is regarded as subjective, so there is a need to verify VSA. Also, many VSAs have not been fine-tuned for contrasting soil types. This could lead to wrong interpretation of soil quality and soil functioning when contrasting sites are compared to each other. We wanted to assess accuracy of VSA, while taking into account soil type. The first objective was to test whether quantitative visual field observations, which form the basis in many VSAs, could be validated with standardized field or laboratory measurements. The second objective was to assess whether quantitative visual field observations are reproducible, when used by observers with contrasting backgrounds. For the validation study, we made quantitative visual observations at 26 cattle farms. Farms were located at sand, clay and peat soils in the North Friesian Woodlands, the Netherlands. Quantitative visual observations evaluated were grass cover, number of biopores, number of roots, soil colour, soil structure, number of earthworms, number of gley mottles and soil compaction. Linear regression analysis showed that four out of eight quantitative visual observations could be well validated with standardized field or laboratory measurements. The following quantitative visual observations correlated well with standardized field or laboratory measurements: grass cover with classified images of surface cover; number of roots with root dry weight; amount of large structure elements with mean weight diameter; and soil colour with soil organic matter content. Correlation coefficients were greater than 0.3, from which half of the correlations were significant. For the reproducibility study, a group of 9 soil scientists and 7

Nanotechnologies risk assessment: a perspective from developing countries

CSIR Research Space (South Africa)

Musee, N

2009-09-01

Full Text Available chemicals in these states: the unique challenges of nanotechnologies from a waste perspective are modeled to develop scenarios of likely impacts to the developing countries. Both qualitative and quantitative risk assessment approaches were developed...

Health risk assessment and the practice of industrial hygiene.

Science.gov (United States)

Paustenbach, D J

1990-07-01

It has been claimed that there may be as many as 2000 airborne chemicals to which persons could be exposed in the workplace and in the community. Of these, occupational exposure limits have been set for approximately 700 chemicals, and only about 30 chemicals have limits for the ambient air. It is likely that some type of health risk assessment methodology will be used to establish limits for the remainder. Although these methods have been used for over 10 yr to set environmental limits, each step of the process (hazard identification, dose-response assessment, exposure assessment, and risk characterization) contains a number of traps into which scientists and risk managers can fall. For example, regulatory approaches to the hazard identification step have allowed little discrimination between the various animal carcinogens, even though these chemicals can vary greatly in their potency and mechanisms of action. In general, epidemiology data have been given little weight compared to the results of rodent bioassays. The dose-response extrapolation process, as generally practiced, often does not present the range of equally plausible values. Procedures which acknowledge and quantitatively account for some or all of the different classes of chemical carcinogens have not been widely adopted. For example, physiologically based pharmacokinetic (PB-PK) and biologically based models need to become a part of future risk assessments. The exposure evaluation portion of risk assessments can now be significantly more valid because of better dispersion models, validated exposure parameters, and the use of computers to account for complex environmental factors. Using these procedures, industrial hygienists are now able to quantitatively estimate the risks caused not only by the inhalation of chemicals but also those caused by dermal contact and incidental ingestion. The appropriate use of risk assessment methods should allow scientists and risk managers to set scientifically valid

EIF onshore discharges : a quantitative environmental risk assessment tool for onshore facilities

Energy Technology Data Exchange (ETDEWEB)

Hagemann, R.; Smit, M.G.D.; Frost, T.K. [Statoil ASA, Stavenger (Norway); Firth, S.K. [Firth Consultants, Bristol (United Kingdom); Stone, K. [WorleyParsons, Victoria, BC (Canada)

2009-07-01

The proper management of environmental risk is a key requirement of StatoilHydro's governing documents and is a key consideration in all phases of StatoilHydro's activities. In order to help manage risks in an effective and sustainable manner, StatoilHydro has led the development of the environmental impact factor (EIF) risk assessment tool. The EIF is utilized by all operators on the Norwegian Continental Shelf for reporting continuous improvements in produced water management to the authorities. The EIF concept has also been applied to evaluate environmental risk from air emissions, offshore oil spills and drilling discharges, discharges from onshore facilities to sea and discharges and spills from onshore installations. In order to identify the remaining hypothetical risk from a new facility, optimized with respect to environmental protection, this paper presented a case study, where the tool was applied to an oil sands steam assisted gravity drainage facility in Alberta. The paper discussed the EIF model and results of the case study. It was concluded that as a result of the use of generic principles for environmental risk assessment, combined with databases with parameter information for common soil and aquifer types, the EIF tool could be applied to any site ranging from wetlands to deserts. 5 refs., 2 tabs., 3 figs.

A spatially explicit and quantitative vulnerability assessment of ecosystem service change in Europe

NARCIS (Netherlands)

Metzger, M.J.; Schröter, D.; Leemans, R.; Cramer, W.

2008-01-01

Environmental change alters ecosystem functioning and may put the provision of services to human at risk. This paper presents a spatially explicit and quantitative assessment of the corresponding vulnerability for Europe, using a new framework designed to answer multidisciplinary policy relevant

Characterizing trabecular bone structure for assessing vertebral fracture risk on volumetric quantitative computed tomography

Science.gov (United States)

Nagarajan, Mahesh B.; Checefsky, Walter A.; Abidin, Anas Z.; Tsai, Halley; Wang, Xixi; Hobbs, Susan K.; Bauer, Jan S.; Baum, Thomas; Wismüller, Axel

2015-03-01

While the proximal femur is preferred for measuring bone mineral density (BMD) in fracture risk estimation, the introduction of volumetric quantitative computed tomography has revealed stronger associations between BMD and spinal fracture status. In this study, we propose to capture properties of trabecular bone structure in spinal vertebrae with advanced second-order statistical features for purposes of fracture risk assessment. For this purpose, axial multi-detector CT (MDCT) images were acquired from 28 spinal vertebrae specimens using a whole-body 256-row CT scanner with a dedicated calibration phantom. A semi-automated method was used to annotate the trabecular compartment in the central vertebral slice with a circular region of interest (ROI) to exclude cortical bone; pixels within were converted to values indicative of BMD. Six second-order statistical features derived from gray-level co-occurrence matrices (GLCM) and the mean BMD within the ROI were then extracted and used in conjunction with a generalized radial basis functions (GRBF) neural network to predict the failure load of the specimens; true failure load was measured through biomechanical testing. Prediction performance was evaluated with a root-mean-square error (RMSE) metric. The best prediction performance was observed with GLCM feature `correlation' (RMSE = 1.02 ± 0.18), which significantly outperformed all other GLCM features (p biomechanical strength prediction in spinal vertebrae can be significantly improved through characterization of trabecular bone structure with GLCM-derived texture features.

A Hierarchal Risk Assessment Model Using the Evidential Reasoning Rule

Directory of Open Access Journals (Sweden)

Xiaoxiao Ji

2017-02-01

Full Text Available This paper aims to develop a hierarchical risk assessment model using the newly-developed evidential reasoning (ER rule, which constitutes a generic conjunctive probabilistic reasoning process. In this paper, we first provide a brief introduction to the basics of the ER rule and emphasize the strengths for representing and aggregating uncertain information from multiple experts and sources. Further, we discuss the key steps of developing the hierarchical risk assessment framework systematically, including (1 formulation of risk assessment hierarchy; (2 representation of both qualitative and quantitative information; (3 elicitation of attribute weights and information reliabilities; (4 aggregation of assessment information using the ER rule and (5 quantification and ranking of risks using utility-based transformation. The proposed hierarchical risk assessment framework can potentially be implemented to various complex and uncertain systems. A case study on the fire/explosion risk assessment of marine vessels demonstrates the applicability of the proposed risk assessment model.

A study on graded approach for risk assessment of the Rokkasho reprocessing plant

International Nuclear Information System (INIS)

Shoji, Tatsuro; Kohata, Yuuji; Takebe, Kazumi; Tamauchi, Yoshikazu; Hayashi, Kazuya; Kurosu, Katsuya

2005-01-01

In a reprocessing plant, radioactive materials exist in several chemical processes and storage facilities, therefore we should evaluate risks of many events with various types, scenarios, frequencies and consequences in order to assess total risk of the plant. In order to assess risks of many events efficiently and effectively, the 'Graded Approach' should be applied to the assessment method taking account of importance of the consequence, complexity of scenarios and necessitated uncertainty. Therefore, we have developed a simplified quantitative method, so-called the 'improved risk index method', based on the 'risk index method' recommended by US NRC as qualitative risk evaluation method for 'Integrated safety analysis (ISA)' of fuel cycle facilities, to enhance quantitability, consistency and traceability in evaluation. The results of the 'improved risk index method' well agree with the detailed PSA in spite of the simplification. We will use this method in combination with the detailed PSA method, and will use the results for risk-informed management/regulation of the Rokkasho reprocessing plant. (author)

Risk assessment techniques for civil aviation security

Energy Technology Data Exchange (ETDEWEB)

Tamasi, Galileo, E-mail: g.tamasi@enac.rupa.i [Ente Nazionale per l' Aviazione Civile-Direzione Progetti, Studi e Ricerche, Via di Villa Ricotti, 42, 00161 Roma (Italy); Demichela, Micaela, E-mail: micaela.demichela@polito.i [SAfeR-Centro Studi su Sicurezza, Affidabilita e Rischi, Dipartimento di Scienza dei Materiali e Ingegneria Chimica, Politecnico di Torino, Corso Duca degli Abruzzi, 24, 10129 Torino (Italy)

2011-08-15

Following the 9/11 terrorists attacks in New York a strong economical effort was made to improve and adapt aviation security, both in infrastructures as in airplanes. National and international guidelines were promptly developed with the objective of creating a security management system able to supervise the identification of risks and the definition and optimization of control measures. Risk assessment techniques are thus crucial in the above process, since an incorrect risk identification and quantification can strongly affect both the security level as the investments needed to reach it. The paper proposes a set of methodologies to qualitatively and quantitatively assess the risk in the security of civil aviation and the risk assessment process based on the threats, criticality and vulnerabilities concepts, highlighting their correlation in determining the level of risk. RAMS techniques are applied to the airport security system in order to analyze the protection equipment for critical facilities located in air-side, allowing also the estimation of the importance of the security improving measures vs. their effectiveness.

Risk assessment techniques for civil aviation security

International Nuclear Information System (INIS)

Tamasi, Galileo; Demichela, Micaela

2011-01-01

Following the 9/11 terrorists attacks in New York a strong economical effort was made to improve and adapt aviation security, both in infrastructures as in airplanes. National and international guidelines were promptly developed with the objective of creating a security management system able to supervise the identification of risks and the definition and optimization of control measures. Risk assessment techniques are thus crucial in the above process, since an incorrect risk identification and quantification can strongly affect both the security level as the investments needed to reach it. The paper proposes a set of methodologies to qualitatively and quantitatively assess the risk in the security of civil aviation and the risk assessment process based on the threats, criticality and vulnerabilities concepts, highlighting their correlation in determining the level of risk. RAMS techniques are applied to the airport security system in order to analyze the protection equipment for critical facilities located in air-side, allowing also the estimation of the importance of the security improving measures vs. their effectiveness.

Food allergy and risk assessment: Current status and future directions

Science.gov (United States)

Remington, Benjamin C.

2017-09-01

Risk analysis is a three part, interactive process that consists of a scientific risk assessment, a risk management strategy and an exchange of information through risk communication. Quantitative risk assessment methodologies are now available and widely used for assessing risks regarding the unintentional consumption of major, regulated allergens but new or modified proteins can also pose a risk of de-novo sensitization. The risks due to de-novo sensitization to new food allergies are harder to quantify. There is a need for a systematic, comprehensive battery of tests and assessment strategy to identify and characterise de-novo sensitization to new proteins and the risks associated with them. A risk assessment must be attuned to answer the risk management questions and needs. Consequently, the hazard and risk assessment methods applied and the desired information are determined by the requested outcome for risk management purposes and decisions to be made. The COST Action network (ImpARAS, www.imparas.eu) has recently started to discuss these risk management criteria from first principles and will continue with the broader subject of improving strategies for allergen risk assessment throughout 2016-2018/9.

A quantitative framework for assessing ecological resilience

Science.gov (United States)

Quantitative approaches to measure and assess resilience are needed to bridge gaps between science, policy, and management. In this paper, we suggest a quantitative framework for assessing ecological resilience. Ecological resilience as an emergent ecosystem phenomenon can be de...

Application of Quantitative Microbial Risk Assessment to analyze the public health risk from poor drinking water quality in a low income area in Accra, Ghana.

Science.gov (United States)

Machdar, E; van der Steen, N P; Raschid-Sally, L; Lens, P N L

2013-04-01

In Accra, Ghana, a majority of inhabitants lives in over-crowded areas with limited access to piped water supply, which is often also intermittent. This study assessed in a densely populated area the risk from microbial contamination of various sources of drinking water, by conducting a Quantitative Microbiological Risk Assessment (QMRA) to estimate the risk to human health from microorganism exposure and dose-response relationships. Furthermore the cost-effectiveness in reducing the disease burden through targeted interventions was evaluated. Five risk pathways for drinking water were identified through a survey (110 families), namely household storage, private yard taps, communal taps, communal wells and water sachets. Samples from each source were analyzed for Escherichia coli and Ascaris contamination. Published ratios between E. coli and other pathogens were used for the QMRA and disease burden calculations. The major part of the burden of disease originated from E. coli O157:H7 (78%) and the least important contributor was Cryptosporidium (0.01%). Other pathogens contributed 16% (Campylobacter), 5% (Rotavirus) and 0.3% (Ascaris). The sum of the disease burden of these pathogens was 0.5 DALYs per person per year, which is much higher than the WHO reference level. The major contamination pathway was found to be household storage. Disinfection of water at household level was the most cost-effective intervention (Water supply network improvements were significantly less cost-effective. Copyright © 2013 Elsevier B.V. All rights reserved.

EPA`s program for risk assessment guidelines: Quantification issues

Energy Technology Data Exchange (ETDEWEB)

Dourson, M.L. [Environmental Protection Agency, Washington, DC (United States)

1990-12-31

The quantitative procedures associated with noncancer risk assessment include reference dose (RfD), benchmark dose, and severity modeling. The RfD, which is part of the EPA risk assessment guidelines, is an estimation of a level that is likely to be without any health risk to sensitive individuals. The RfD requires two major judgments: the first is choice of a critical effect(s) and its No Observed Adverse Effect Level (NOAEL); the second judgment is choice of an uncertainty factor. This paper discusses major assumptions and limitations of the RfD model.

A comparison of risk assessments on Campylobacter in broiler meat

DEFF Research Database (Denmark)

Nauta, Maarten; Hill, Andy; Rosenquist, Hanne

2009-01-01

In recent years. several quantitative risk assessments for Campylobacter in broiler meat have been developed to support risk managers in controlling this pathogen. The models encompass some or all of the consecutive stages in the broiler meat production chain: primary production, industrial...... of slaughter, the prevalence is most likely to be either very low (95%). In evaluating control strategies, all models find a negligible effect of logistic slaughter, the separate processing of positive and negative flocks. Also, all risk assessments conclude that the most effective intervention measures aim...... processing, consumer food preparation,and the close-response relationship. The modelling approaches vary between the models, and this has supported the progress of risk assessment as a research discipline. The risk assessments are not only used to assess the human incidence of campylobacteriosis due...

Innovations in Quantitative Risk Management

CERN Document Server

Scherer, Matthias; Zagst, Rudi

2015-01-01

Quantitative models are omnipresent –but often controversially discussed– in todays risk management practice. New regulations, innovative financial products, and advances in valuation techniques provide a continuous flow of challenging problems for financial engineers and risk managers alike. Designing a sound stochastic model requires finding a careful balance between parsimonious model assumptions, mathematical viability, and interpretability of the output. Moreover, data requirements and the end-user training are to be considered as well. The KPMG Center of Excellence in Risk Management conference Risk Management Reloaded and this proceedings volume contribute to bridging the gap between academia –providing methodological advances– and practice –having a firm understanding of the economic conditions in which a given model is used. Discussed fields of application range from asset management, credit risk, and energy to risk management issues in insurance. Methodologically, dependence modeling...

Microbial risk assessment of Vibrio spp. in seafood products in Mexico

Directory of Open Access Journals (Sweden)

Karla M López-Hernández

2014-05-01

Full Text Available Food-borne diseases are among the major public health problems that currently exist. Microbiological risk assessment is a process used to evaluate the hidden hazards in food, the likelihood of exposure to these hazards and their impact on public health. Risk assessment is performed in four steps: hazard identification, hazard characterization, assessment of exposure and risk characterization. According to the process/response microbial risk assessment is classified in two categories, qualitative and quantitative. The aim of this review is to underline the importance of implementing assessments in seafood that is usually consumed raw, strengthening access to good quality and safe food for the consumer’s benefit and to stress the necessity of microbiological risks assessments in Mexico.

New Approaches to Transport Project Assessment: Reference Scenario Forecasting and Quantitative Risk Analysis

DEFF Research Database (Denmark)

Salling, Kim Bang

2010-01-01

however has proved that the point estimates derived from such analyses are embedded with a large degree of uncertainty. Thus, a new scheme was proposed in terms of applying quantitative risk analysis (QRA) and Monte Carlo simulation in order to represent the uncertainties within the cost-benefit analysis....... Additionally, the handling of uncertainties is supplemented by making use of the principle of Optimism Bias, which depicts the historical tendency of overestimating transport related benefits (user demands i.e. travel time savings) and underestimating investment costs....

Environmental risk assessment as the basis for mine closure at Iscor Mining

Energy Technology Data Exchange (ETDEWEB)

Swart, S.J.; Pulles, W.; Boer, R.H.; Kirkaldy, J.; Pettit, C. [Iscor Mining, Pretoria (South Africa). Environmental Management Services

1998-01-01

This paper discusses the principles and application of risk assessment and management as the basis for environmental management within the mining industry. Unlike in other industries, mines are required to obtain closure certificates in terms of section 12 for the South African Minerals Act, which should ultimately release them from further environmental responsibilities. The focus shifts from conventional minimum legal compliance management to management of real environmental risks. The risk assessment approach has been applied to the planning of mine closure at Iscor`s Durban Navigation Collieries (Durnacol) in Kwa-Zulu Natal and certain key risk issues such as the long-term risk of water pollution from coal discard dumps have already progressed to fully quantitative risk assessment. This paper discussed the process which has been followed to date, with particular emphasis on the most recent phase, namely quantitative risk assessment and management of pollution from coal discard dumps. it is believed that the approach that is being pioneered at Durnacoal and which overcomes some of the more obvious deficineices of both the Environmental Risk Assessment Management (EMPR) and the traditional process will ultimately serve as the mode for all responsible mines in South Africa. It is also believed that this approach will enable the authorities to issue closure certificates with the confidence that there will be no unforeseen surprises in the years after closure. 9 figs., 1 tab.

Quantitative and Qualitative Assessment of Pulmonary Emphysema with T2-Weighted PROPELLER MRI in a High-Risk Population Compared to Low-Dose CT.

Science.gov (United States)

Meier-Schroers, Michael; Sprinkart, Alois Martin; Becker, Manuel; Homsi, Rami; Thomas, Daniel

2018-03-07

 To determine the suitability of T2-weighted PROPELLER MRI for the assessment of pulmonary emphysema.  60 participants in a lung cancer screening program (30 subjects with pulmonary emphysema, and 30 control subjects without emphysema) were included for this retrospective study. All subjects were examined with low-dose CT (LDCT) and MRI within the screening program. The use of a T2-weighted PROPELLER sequence for the assessment of emphysema was analyzed and correlated with the results of LDCT. The presence and the extent of pulmonary emphysema were first assessed qualitatively using a three-point score, and then quantitatively with a semi-automated software program to obtain emphysema indices.  All 30 cases with pulmonary emphysema were accurately detected by MRI. There were 3 cases with emphysema according to MRI without emphysematous changes on LDCT (false-positive results). The qualitative scores as well as the emphysema indices were significantly higher in the emphysema group compared to the control group for MRI and LDCT (p emphysema group and r = 0.668/p emphysema index: r = 0.960/p emphysema group and r = 0.746/p pulmonary emphysema may be assessed qualitatively and quantitatively by T2-weighted PROPELLER MRI with very good correlation to LDCT.   · T2-weighted PROPELLER MRI may be suitable for the assessment of pulmonary emphysema.. · There was significant correlation between MRI and LDCT regarding qualitative scores and quantitative emphysema indices in our study with correlation coefficients for different subgroups ranging from r = 0.668 to r = 0.960.. · T2-weighted PROPELLER MRI may have the potential to be used for follow-up examinations in patients with severe emphysema to avoid radiation exposure of repeated CTs.. · Meier-Schroers M, Sprinkart AM, Becker M et al. Quantitative and Qualitative Assessment of Pulmonary Emphysema with T2-Weighted PROPELLER MRI in a High-Risk Population Compared to Low-Dose CT

Quantitative microbial risk assessment for spray irrigation of dairy manure based on an empirical fate and transport model

Science.gov (United States)

Burch, Tucker R; Spencer, Susan K.; Stokdyk, Joel; Kieke, Burney A; Larson, Rebecca A; Firnstahl, Aaron; Rule, Ana M; Borchardt, Mark A.

2017-01-01

BACKGROUND: Spray irrigation for land-applying livestock manure is increasing in the United States as farms become larger and economies of scale make manure irrigation affordable. Human health risks from exposure to zoonotic pathogens aerosolized during manure irrigation are not well understood. OBJECTIVES: We aimed to a) estimate human health risks due to aerosolized zoonotic pathogens downwind of spray-irrigated dairy manure; and b) determine which factors (e.g., distance, weather conditions) have the greatest influence on risk estimates. METHODS: We sampled downwind air concentrations of manure-borne fecal indicators and zoonotic pathogens during 21 full-scale dairy manure irri- gation events at three farms. We fit these data to hierarchical empirical models and used model outputs in a quantitative microbial risk assessment (QMRA) to estimate risk [probability of acute gastrointestinal illness (AGI)] for individuals exposed to spray-irrigated dairy manure containing Campylobacter jejuni, enterohemorrhagic Escherichia coli (EHEC), or Salmonella spp. RESULTS: Median risk estimates from Monte Carlo simulations ranged from 10−5 to 10−2 and decreased with distance from the source. Risk estimates for Salmonella or EHEC-related AGI were most sensitive to the assumed level of pathogen prevalence in dairy manure, while risk estimates for C. jejuni were not sensitive to any single variable. Airborne microbe concentrations were negatively associated with distance and positively associated with wind speed, both of which were retained in models as a significant predictor more often than relative humidity, solar irradiation, or temperature. CONCLUSIONS: Our model-based estimates suggest that reducing pathogen prevalence and concentration in source manure would reduce the risk of AGI from exposure to manure irrigation, and that increasing the distance from irrigated manure (i.e., setbacks) and limiting irrigation to times of low wind speed may also reduce risk.

A Quantitative Climate-Match Score for Risk-Assessment Screening of Reptile and Amphibian Introductions

Science.gov (United States)

van Wilgen, Nicola J.; Roura-Pascual, Núria; Richardson, David M.

2009-09-01

Assessing climatic suitability provides a good preliminary estimate of the invasive potential of a species to inform risk assessment. We examined two approaches for bioclimatic modeling for 67 reptile and amphibian species introduced to California and Florida. First, we modeled the worldwide distribution of the biomes found in the introduced range to highlight similar areas worldwide from which invaders might arise. Second, we modeled potentially suitable environments for species based on climatic factors in their native ranges, using three sources of distribution data. Performance of the three datasets and both approaches were compared for each species. Climate match was positively correlated with species establishment success (maximum predicted suitability in the introduced range was more strongly correlated with establishment success than mean suitability). Data assembled from the Global Amphibian Assessment through NatureServe provided the most accurate models for amphibians, while ecoregion data compiled by the World Wide Fund for Nature yielded models which described reptile climatic suitability better than available point-locality data. We present three methods of assigning a climate-match score for use in risk assessment using both the mean and maximum climatic suitabilities. Managers may choose to use different methods depending on the stringency of the assessment and the available data, facilitating higher resolution and accuracy for herpetofaunal risk assessment. Climate-matching has inherent limitations and other factors pertaining to ecological interactions and life-history traits must also be considered for thorough risk assessment.

Assessing the value of risk: Perspectives on the role of risk information in decision making

International Nuclear Information System (INIS)

Egan, M.; Smith, Graham; Maul, P.

1999-01-01

The authors of this paper profess no formal ethical or philosophical training from which to develop their position on Values in Decisions on Risk. However, as scientists with practical experience in carrying out a range of quantitative studies, we consider that we have some understanding of the strengths and weaknesses inherent in environmental risk assessment. Moreover, in attempting to use the results of such assessments, we have observed some of the ways in which quantitative risk information is used and abused. In this paper, therefore, we offer a practitioner's perspective that underlines the essential role of risk as a tool to inform and guide decisions, while at the same time emphasising the need for its proportionate use in a complex arena. We draw on experience that includes assessments for radioactive waste management and disposal, but also incorporates a range of assignments where assessment of the scale of potential environmental liabilities was a critical factor in decision making. We do not pretend to offer a resolution to the challenges laid before this Symposium, but seek to explore common themes and lessons learned regarding the role of risk information in goal-setting, performance monitoring and the overall decision process. Policy makers and regulators must act responsibly to protect confidence, not just the health of people and the environment. In doing this, to ignore risk information as a key component of strategic thinking is equally as disproportionate as making it the sole basis for decision making. There is a clear need to explain better the basis of, and motives behind, decisions - not only in terms of transparency in risk assessment but also to distinguish between the scientific and the socio-political component of the argument

Assessing the value of risk: Perspectives on the role of risk information in decision making

Energy Technology Data Exchange (ETDEWEB)

Egan, M.; Smith, Graham; Maul, P. [QuantiSci Limited, Henley-on-Thames (United Kingdom)

1999-12-01

The authors of this paper profess no formal ethical or philosophical training from which to develop their position on Values in Decisions on Risk. However, as scientists with practical experience in carrying out a range of quantitative studies, we consider that we have some understanding of the strengths and weaknesses inherent in environmental risk assessment. Moreover, in attempting to use the results of such assessments, we have observed some of the ways in which quantitative risk information is used and abused. In this paper, therefore, we offer a practitioner's perspective that underlines the essential role of risk as a tool to inform and guide decisions, while at the same time emphasising the need for its proportionate use in a complex arena. We draw on experience that includes assessments for radioactive waste management and disposal, but also incorporates a range of assignments where assessment of the scale of potential environmental liabilities was a critical factor in decision making. We do not pretend to offer a resolution to the challenges laid before this Symposium, but seek to explore common themes and lessons learned regarding the role of risk information in goal-setting, performance monitoring and the overall decision process. Policy makers and regulators must act responsibly to protect confidence, not just the health of people and the environment. In doing this, to ignore risk information as a key component of strategic thinking is equally as disproportionate as making it the sole basis for decision making. There is a clear need to explain better the basis of, and motives behind, decisions - not only in terms of transparency in risk assessment but also to distinguish between the scientific and the socio-political component of the argument.

Development of a quantitative risk standard

International Nuclear Information System (INIS)

Temme, M.I.

1982-01-01

IEEE Working Group SC-5.4 is developing a quantitative risk standard for LWR plant design and operation. The paper describes the Working Group's conclusions on significant issues, including the scope of the standard, the need to define the process (i.e., PRA calculation) for meeting risk criteria, the need for PRA quality requirements and the importance of distinguishing standards from goals. The paper also describes the Working Group's approach to writing this standard

Microbial risk assessment and its implications for risk management in urban water systems

OpenAIRE

Westrell, Therese

2004-01-01

Infectious disease can be transmitted via various environmental pathways, many of which are incorporated into our water and wastewater systems. Quantitative microbial risk assessment (QMRA) can be a valuable tool in identifying hazard exposure pathways and estimating their associated health impacts. QMRA can be applied to establish standards and guidelines and has been adopted by the World Health Organisation for the management of risks from water-related infectious diseases. This thesis aims...

Probabilistic Risk Assessment Procedures Guide for NASA Managers and Practitioners (Second Edition)

Science.gov (United States)

Stamatelatos,Michael; Dezfuli, Homayoon; Apostolakis, George; Everline, Chester; Guarro, Sergio; Mathias, Donovan; Mosleh, Ali; Paulos, Todd; Riha, David; Smith, Curtis;

Bayesian Networks for enterprise risk assessment

Science.gov (United States)

Bonafede, C. E.; Giudici, P.

2007-08-01

According to different typologies of activity and priority, risks can assume diverse meanings and it can be assessed in different ways. Risk, in general, is measured in terms of a probability combination of an event (frequency) and its consequence (impact). To estimate the frequency and the impact (severity) historical data or expert opinions (either qualitative or quantitative data) are used. Moreover, qualitative data must be converted in numerical values or bounds to be used in the model. In the case of enterprise risk assessment the considered risks are, for instance, strategic, operational, legal and of image, which many times are difficult to be quantified. So in most cases only expert data, gathered by scorecard approaches, are available for risk analysis. The Bayesian Networks (BNs) are a useful tool to integrate different information and in particular to study the risk's joint distribution by using data collected from experts. In this paper we want to show a possible approach for building a BN in the particular case in which only prior probabilities of node states and marginal correlations between nodes are available, and when the variables have only two states.

Formal safety assessment based on relative risks model in ship navigation

Energy Technology Data Exchange (ETDEWEB)

Hu Shenping [Merchant Marine College, Shanghai Maritime University, 1550, Pudong Dadao, Shanghai 200135 (China)]. E-mail: sphu@mmc.shmtu.edu.cn; Fang Quangen [Merchant Marine College, Shanghai Maritime University, 1550, Pudong Dadao, Shanghai 200135 (China)]. E-mail: qgfang@mmc.shmtu.edu.cn; Xia Haibo [Merchant Marine College, Shanghai Maritime University, 1550, Pudong Dadao, Shanghai 200135 (China)]. E-mail: hbxia@mmc.shmtu.edu.cn; Xi Yongtao [Merchant Marine College, Shanghai Maritime University, 1550, Pudong Dadao, Shanghai 200135 (China)]. E-mail: xiyt@mmc.shmtu.edu.cn

2007-03-15

Formal safety assessment (FSA) is a structured and systematic methodology aiming at enhancing maritime safety. It has been gradually and broadly used in the shipping industry nowadays around the world. On the basis of analysis and conclusion of FSA approach, this paper discusses quantitative risk assessment and generic risk model in FSA, especially frequency and severity criteria in ship navigation. Then it puts forward a new model based on relative risk assessment (MRRA). The model presents a risk-assessment approach based on fuzzy functions and takes five factors into account, including detailed information about accident characteristics. It has already been used for the assessment of pilotage safety in Shanghai harbor, China. Consequently, it can be proved that MRRA is a useful method to solve the problems in the risk assessment of ship navigation safety in practice.

Formal safety assessment based on relative risks model in ship navigation

International Nuclear Information System (INIS)

Hu Shenping; Fang Quangen; Xia Haibo; Xi Yongtao

2007-01-01

Formal safety assessment (FSA) is a structured and systematic methodology aiming at enhancing maritime safety. It has been gradually and broadly used in the shipping industry nowadays around the world. On the basis of analysis and conclusion of FSA approach, this paper discusses quantitative risk assessment and generic risk model in FSA, especially frequency and severity criteria in ship navigation. Then it puts forward a new model based on relative risk assessment (MRRA). The model presents a risk-assessment approach based on fuzzy functions and takes five factors into account, including detailed information about accident characteristics. It has already been used for the assessment of pilotage safety in Shanghai harbor, China. Consequently, it can be proved that MRRA is a useful method to solve the problems in the risk assessment of ship navigation safety in practice

Integration of quantitative risk assessment in the health impact assessment of the recently amended Hungarian anti-smoking policy

DEFF Research Database (Denmark)

Ádám, Balázs; Molnár, Ágnes; Gulis, Gabriel

2011-01-01

Health impact assessments (HIA) dominantly apply only qualitative evaluation, although a comprehensive HIA ideally integrates both qualitative and quantitative evidence and methods, since quantification has several advantages when using assessment results in the decision making process......-smokers to introduce smoking ban in closed public places, workplaces and public transport vehicles. Full chain approach was used to identify basic rules for prioritizing the major impact pathways with special attention to the feasibility of quantifying exposure and outcome. Exposure assessment relied on international...... experiences, while outcome assessment calculated measures of disease burden, like attributable death and disability adjusted life years, for a baseline and a predicted situation after the proposed changes take place. The major impact of the proposal was identified to decreases prevalence of active and passive...

The role of risk assessment in the nuclear regulatory process

International Nuclear Information System (INIS)

Levine, S.

1979-01-01

Since the publication of the Reactor Safety Study in the USA, the basic tasks of which are summarised, the use of quantitative risk-assessment techniques for the safety of nuclear power plants has increased considerably. Some of the viewpoints expressed on the use of these techniques are examined, and their limitations are discussed. Areas where risk-assessment techniques are applied by the NRC are listed and some recent examples are discussed. Risk assessment has also been used as a criteria for deciding the topics for the NRC's recommendations for research programs. It is concluded that the major contribution of risk assessment techniques should be in the form of background analyses that will aid decision making and could also significantly affect the scope and content of regulatory reviews. (UK)

A comparison of integrated safety analysis and probabilistic risk assessment

International Nuclear Information System (INIS)

Damon, Dennis R.; Mattern, Kevin S.

2013-01-01

The U.S. Nuclear Regulatory Commission conducted a comparison of two standard tools for risk informing the regulatory process, namely, the Probabilistic Risk Assessment (PRA) and the Integrated Safety Analysis (ISA). PRA is a calculation of risk metrics, such as Large Early Release Frequency (LERF), and has been used to assess the safety of all commercial power reactors. ISA is an analysis required for fuel cycle facilities (FCFs) licensed to possess potentially critical quantities of special nuclear material. A PRA is usually more detailed and uses more refined models and data than an ISA, in order to obtain reasonable quantitative estimates of risk. PRA is considered fully quantitative, while most ISAs are typically only partially quantitative. The extension of PRA methodology to augment or supplant ISAs in FCFs has long been considered. However, fuel cycle facilities have a wide variety of possible accident consequences, rather than a few surrogates like LERF or core damage as used for reactors. It has been noted that a fuel cycle PRA could be used to better focus attention on the most risk-significant structures, systems, components, and operator actions. ISA and PRA both identify accident sequences; however, their treatment is quite different. ISA's identify accidents that lead to high or intermediate consequences, as defined in 10 Code of Federal Regulations (CFR) 70, and develop a set of Items Relied on For Safety (IROFS) to assure adherence to performance criteria. PRAs identify potential accident scenarios and estimate their frequency and consequences to obtain risk metrics. It is acceptable for ISAs to provide bounding evaluations of accident consequences and likelihoods in order to establish acceptable safety; but PRA applications usually require a reasonable quantitative estimate, and often obtain metrics of uncertainty. This paper provides the background, features, and methodology associated with the PRA and ISA. The differences between the

Quantitative microbial risk assessment for Escherichia coli O157:H7, Salmonella enterica, and Listeria monocytogenes in leafy green vegetables consumed at salad bars, based on modeling supply chain logistics.

Science.gov (United States)

Tromp, S O; Rijgersberg, H; Franz, E

2010-10-01

Quantitative microbial risk assessments do not usually account for the planning and ordering mechanisms (logistics) of a food supply chain. These mechanisms and consumer demand determine the storage and delay times of products. The aim of this study was to quantitatively assess the difference between simulating supply chain logistics (MOD) and assuming fixed storage times (FIX) in microbial risk estimation for the supply chain of fresh-cut leafy green vegetables destined for working-canteen salad bars. The results of the FIX model were previously published (E. Franz, S. O. Tromp, H. Rijgersberg, and H. J. van der Fels-Klerx, J. Food Prot. 73:274-285, 2010). Pathogen growth was modeled using stochastic discrete-event simulation of the applied logistics concept. The public health effects were assessed by conducting an exposure assessment and risk characterization. The relative growths of Escherichia coli O157 (17%) and Salmonella enterica (15%) were identical in the MOD and FIX models. In contrast, the relative growth of Listeria monocytogenes was considerably higher in the MOD model (1,156%) than in the FIX model (194%). The probability of L. monocytogenes infection in The Netherlands was higher in the MOD model (5.18×10(-8)) than in the FIX model (1.23×10(-8)). The risk of listeriosis-induced fetal mortality in the perinatal population increased from 1.24×10(-4) (FIX) to 1.66×10(-4) (MOD). Modeling the probabilistic nature of supply chain logistics is of additional value for microbial risk assessments regarding psychrotrophic pathogens in food products for which time and temperature are the postharvest preventive measures in guaranteeing food safety.

Advancing effects analysis for integrated, large-scale wildfire risk assessment

Science.gov (United States)

Matthew P. Thompson; David E. Calkin; Julie W. Gilbertson-Day; Alan A. Ager

2011-01-01

In this article, we describe the design and development of a quantitative, geospatial risk assessment tool intended to facilitate monitoring trends in wildfire risk over time and to provide information useful in prioritizing fuels treatments and mitigation measures. The research effort is designed to develop, from a strategic view, a first approximation of how both...

Qualitative and quantitative ultrasound assessment of gastric content

Directory of Open Access Journals (Sweden)

Flora Margarida Barra Bisinotto

Full Text Available Summary Objective: Pulmonary aspiration of the gastric contents is one of the most feared complications in anesthesia. Its prevention depends on preoperative fasting as well as identification of risky patients. A reliable diagnostic tool to assess gastric volume is currently lacking. The aim of this study performed on volunteers was to evaluate the feasibility of ultrasonography to identify qualitative and quantitative gastric content. Method: A standardized gastric scanning protocol was applied on 67 healthy volunteers to assess the gastric antrum in four different situations: fasting, after ingesting clear fluid, milk and a solid meal. A qualitative and quantitative assessment of the gastric content in the antrum was performed by a blinded sonographer. The antrum was considered either as empty, or containing clear or thick fluid, or solids. Total gastric volume was predicted based on a cross-sectional area of the antrum. A p-value less than 0.05 was considered statistically significant. Results: For each type of gastric content, the sonographic characteristics of the antrum and its content were described and illustrated. Sonographic qualitative assessment allowed to distinguish between an empty stomach and one with different kinds of meal. The predicted gastric volume was significantly larger after the consumption of any food source compared to fasting. Conclusion: Bedside sonography can determine the nature of gastric content. It is also possible to estimate the difference between an empty gastric antrum and one that has some food in it. Such information may be useful to estimate the risk of aspiration, particularly in situations when prandial status is unknown or uncertain.

Qualitative and quantitative ultrasound assessment of gastric content.

Science.gov (United States)

Bisinotto, Flora Margarida Barra; Pansani, Patrícia Luísa; Silveira, Luciano Alves Matias da; Naves, Aline de Araújo; Peixoto, Ana Cristina Abdu; Lima, Hellen Moreira de; Martins, Laura Bisinotto

2017-02-01

Pulmonary aspiration of the gastric contents is one of the most feared complications in anesthesia. Its prevention depends on preoperative fasting as well as identification of risky patients. A reliable diagnostic tool to assess gastric volume is currently lacking. The aim of this study performed on volunteers was to evaluate the feasibility of ultrasonography to identify qualitative and quantitative gastric content. A standardized gastric scanning protocol was applied on 67 healthy volunteers to assess the gastric antrum in four different situations: fasting, after ingesting clear fluid, milk and a solid meal. A qualitative and quantitative assessment of the gastric content in the antrum was performed by a blinded sonographer. The antrum was considered either as empty, or containing clear or thick fluid, or solids. Total gastric volume was predicted based on a cross-sectional area of the antrum. A p-value less than 0.05 was considered statistically significant. For each type of gastric content, the sonographic characteristics of the antrum and its content were described and illustrated. Sonographic qualitative assessment allowed to distinguish between an empty stomach and one with different kinds of meal. The predicted gastric volume was significantly larger after the consumption of any food source compared to fasting. Bedside sonography can determine the nature of gastric content. It is also possible to estimate the difference between an empty gastric antrum and one that has some food in it. Such information may be useful to estimate the risk of aspiration, particularly in situations when prandial status is unknown or uncertain.

A quantitative risk assessment model to evaluate effective border control measures for rabies prevention

Science.gov (United States)

Weng, Hsin-Yi; Wu, Pei-I; Yang, Ping-Cheng; Tsai, Yi-Lun; Chang, Chao-Chin

2009-01-01

Border control is the primary method to prevent rabies emergence. This study developed a quantitative risk model incorporating stochastic processes to evaluate whether border control measures could efficiently prevent rabies introduction through importation of cats and dogs using Taiwan as an example. Both legal importation and illegal smuggling were investigated. The impacts of reduced quarantine and/or waiting period on the risk of rabies introduction were also evaluated. The results showed that Taiwan’s current animal importation policy could effectively prevent rabies introduction through legal importation of cats and dogs. The median risk of a rabid animal to penetrate current border control measures and enter Taiwan was 5.33 × 10−8 (95th percentile: 3.20 × 10−7). However, illegal smuggling may pose Taiwan to the great risk of rabies emergence. Reduction of quarantine and/or waiting period would affect the risk differently, depending on the applied assumptions, such as increased vaccination coverage, enforced custom checking, and/or change in number of legal importations. Although the changes in the estimated risk under the assumed alternatives were not substantial except for completely abolishing quarantine, the consequences of rabies introduction may yet be considered to be significant in a rabies-free area. Therefore, a comprehensive benefit-cost analysis needs to be conducted before recommending these alternative measures. PMID:19822125

Qualitative risk assessment of subsurface barriers in applications supporting retrieval of SST waste

International Nuclear Information System (INIS)

Treat, R.L.

1994-04-01

This report provides a brief, qualitative assessment of risks associated with the potential use of impermeable surface barriers installed around and beneath Hanford Site single-shell tanks (SSTs) to support the retrieval of wastes from those tanks. These risks are compared to qualitative assessment of costs and risks associated with a case in which barriers are not used. A quantitative assessment of costs and risks associated with these two cases will be prepared and documented in a companion report. The companion report will compare quantitatively the costs and risks of several retrieval options with varying parameters, such as effectiveness of retrieval, effectiveness of subsurface barriers, and the use of surface barriers. For ease of comparison of qualitative risks, a case in which impermeable subsurface barriers are used in conjunction with another technology to remove tank waste is referred, to in this report as the Barrier Case. A case in which waste removal technologies are used without employing a subsurface barrier is referred to as the No Barrier Case. The technologies associated with each case are described in the following sections

Recent developments in carcinogenic risk assessment

International Nuclear Information System (INIS)

Krewski, D.; Murdoch, D.; Withey, J.R.

1989-01-01

In this paper, recent developments in the quantitative assessment of carcinogenic risks based on toxicological and epidemiological data are reviewed. In particular, model-free approaches to low-dose risk assessment which involve only the assumption of low-dose linearity are considered. Measures of carcinogenic potency which avoid the need to extrapolate to low doses are also described. The allometric bases for converting risk estimates between species are then discussed. Pharmacokinetic models for determining the dose delivered to the target tissue are examined, and the implications of using such models in extrapolating between doses, of exposure, and species are examined. The application of these concepts in chemical and radiation carcinogenesis is illustrated by means of brief case studies of methylene chloride and Rn. Biologically motivated cancer models based on the initiation-promotion-progression theory of carcinogenesis are discussed and compared with the classical multistage model. The estimation of risks with time-dependent exposure patterns is considered, and conditions under which the use of a time-weighted average dose is appropriate are identified. Finally, the estimation of carcinogenic risks posed by exposure to complex mixtures is explored. 92 references

Development of a semi-quantitative risk assessment model for evaluating environmental threat posed by the three first EU watch-list pharmaceuticals to urban wastewater treatment plants: An Irish case study.

Science.gov (United States)

Tahar, Alexandre; Tiedeken, Erin Jo; Clifford, Eoghan; Cummins, Enda; Rowan, Neil

2017-12-15

Contamination of receiving waters with pharmaceutical compounds is of pressing concern. This constitutes the first study to report on the development of a semi-quantitative risk assessment (RA) model for evaluating the environmental threat posed by three EU watch list pharmaceutical compounds namely, diclofenac, 17-beta-estradiol and 17-alpha-ethinylestradiol, to aquatic ecosystems using Irish data as a case study. This RA model adopts the Irish Environmental Protection Agency Source-Pathway-Receptor concept to define relevant parameters for calculating low, medium or high risk score for each agglomeration of wastewater treatment plant (WWTP), which include catchment, treatments, operational and management factors. This RA model may potentially be used on a national scale to (i) identify WWTPs that pose a particular risk as regards releasing disproportionally high levels of these pharmaceutical compounds, and (ii) help identify priority locations for introducing or upgrading control measures (e.g. tertiary treatment, source reduction). To assess risks for these substances of emerging concern, the model was applied to 16 urban WWTPs located in different regions in Ireland that were scored for the three different compounds and ranked as low, medium or high risk. As a validation proxy, this case study used limited monitoring data recorded at some these plants receiving waters. It is envisaged that this semi-quantitative RA approach may aid other EU countries investigate and screen for potential risks where limited measured or predicted environmental pollutant concentrations and/or hydrological data are available. This model is semi-quantitative, as other factors such as influence of climate change and drug usage or prescription data will need to be considered in a future point for estimating and predicting risks. Copyright © 2017 Elsevier B.V. All rights reserved.

Presentation of a Software Method for Use of Risk Assessment in Building Fire Safety Measure Optimization

Directory of Open Access Journals (Sweden)

A. R. Koohpaei

2012-05-01

Full Text Available Background and aims: The property loss and physical injuries due to fire events in buildings demonstrate the necessity of implementation of efficient and performance based fire safety measures. Effective and high efficiency protection is possible when design and selection of protection measures are based on risk assessment. This study aims at presenting a software method to make possible selection and design of building fire safety measures based upon quantitative risk assessment and building characteristics. Methods: based on “Fire Risk Assessment Method for Engineer (FRAME” a program in MATLB software was written. The first section of this program, according to the FRAME method and based on the specification of a building, calculates the potential risk and acceptable risk level. In the second section, according to potential risk, acceptable risk level and the fire risk level that user want, program calculate concession of protective factor for that building.Results: The prepared software make it possible to assign the fire safety measure based on quantitative risk level and all building specifications. All calculations were performed with 0.001 of precision and the accuracy of this software was assessed with handmade calculations. During the use of the software if an error occurs in calculations, it can be distinguished in the output. Conclusion: Application of quantitative risk assessment is a suitable tool for increasing of efficiency in designing and execution of fire protection measure in building. With using this software the selected fire safety measure would be more efficient and suitable since the selection of fire safety measures performed on risk assessment and particular specification of a building. Moreover fire risk in the building can be managed easily and carefully.

National report of France. Risks and risk assessment according to the law of France

International Nuclear Information System (INIS)

Backhaus, L.

1980-01-01

This report encompasses the following chapters: the fundamentals of the law governing conventional industrial facilities, normative principles of atomic energy law; risk assessments in the law concerning conventional industrial facilities, risk assessment in the law concerning nuclear power plants; application of probabilistic methods in the field of nuclear safety, probabilistic methods in the safety assessment of modern aircraft; concept of risk in police regulations, 'Theorie des risques anormaux de voisinage' in public law on indemnification, causality and probability in civil law. It is stated in this report that in France, too, the idea of completely reforming the procedures of safety analysis is gaining ground, and the change from hitherto applied deterministic methods to logical risk analyses and probabilistic licensing is to be expected in the long run. This change will most probably be effected by defining a general risk acceptance criterion by means of conventions and, on the basis of this generally accepted criterion, proceed to defining an accepted, quantitatively determined risk standard both for a complete plant and for individual systems. (orig./HSCH) [de

Risk assessment of mitigated domino scenarios in process facilities

International Nuclear Information System (INIS)

Landucci, Gabriele; Necci, Amos; Antonioni, Giacomo; Argenti, Francesca; Cozzani, Valerio

2017-01-01

The propagation of accidents among process units may lead to severe cascading events or domino effects with catastrophic consequences. Prevention, mitigation and management of domino scenarios is of utmost importance and may be achieved in industrial facilities through the adoption of multiple safety layers. The present study was aimed at developing an innovative methodology to address the quantitative risk assessment (QRA) of domino scenarios accounting for the presence and role of safety barriers. Based on the expected performance of safety barriers, a dedicated event tree analysis allowed the identification and the assessment of the frequencies of the different end-point events deriving from unmitigated and partially mitigated domino chains. Specific criteria were introduced in consequence analysis to consider the mitigation effects of end-point scenarios deriving from safety barriers. Individual and societal risk indexes were calculated accounting for safety barriers and the mitigated scenarios that may result from their actions. The application of the methodology to case-studies of industrial interest proved the importance of introducing a specific systematic and quantitative analysis of safety barrier performance when addressing escalation leading to domino effect. - Highlights: • A methodology was developed to account for safety barrier performance in escalation prevention. • The methodology allows quantitative assessment accounting for safety barrier performance. • A detailed analysis of transient mitigated scenarios is allowed by the developed procedure. • The procedure allows accounting for safety barrier performance in QRA of domino scenarios. • An important reduction in the risk due to domino scenarios is evidenced when considering safety barriers.

Dose response models and a quantitative microbial risk assessment framework for the Mycobacterium avium complex that account for recent developments in molecular biology, taxonomy, and epidemiology.

Science.gov (United States)

Hamilton, Kerry A; Weir, Mark H; Haas, Charles N

2017-02-01

Mycobacterium avium complex (MAC) is a group of environmentally-transmitted pathogens of great public health importance. This group is known to be harbored, amplified, and selected for more human-virulent characteristics by amoeba species in aquatic biofilms. However, a quantitative microbial risk assessment (QMRA) has not been performed due to the lack of dose response models resulting from significant heterogeneity within even a single species or subspecies of MAC, as well as the range of human susceptibilities to mycobacterial disease. The primary human-relevant species and subspecies responsible for the majority of the human disease burden and present in drinking water, biofilms, and soil are M. avium subsp. hominissuis, M. intracellulare, and M. chimaera. A critical review of the published literature identified important health endpoints, exposure routes, and susceptible populations for MAC risk assessment. In addition, data sets for quantitative dose-response functions were extracted from published in vivo animal dosing experiments. As a result, seven new exponential dose response models for human-relevant species of MAC with endpoints of lung lesions, death, disseminated infection, liver infection, and lymph node lesions are proposed. Although current physical and biochemical tests used in clinical settings do not differentiate between M. avium and M. intracellulare, differentiating between environmental species and subspecies of the MAC can aid in the assessment of health risks and control of MAC sources. A framework is proposed for incorporating the proposed dose response models into susceptible population- and exposure route-specific QMRA models. Copyright © 2016 Elsevier Ltd. All rights reserved.

Risk assessment for SAGD well blowouts

Energy Technology Data Exchange (ETDEWEB)

Worth, D.; Alhanati, F.; Lastiwka, M. [C-FER Technologies, Edmonton, AB (Canada); Crepin, S. [Petrocedeno, Caracas (Venezuela)

2008-10-15

This paper discussed a steam assisted gravity drainage (SAGD) pilot project currently being conducted in Venezuela's Orinoco Belt. A risk assessment was conducted as part of the pilot program in order to evaluate the use of single barrier completions in conjunction with a blowout response plan. The study considered 3 options: (1) an isolated double barrier completion with a downhole safety valve (DHSV) in the production tubing string and a packer in the production casing annulus; (2) a partially isolated completion with no DHSV and a packer in the production casing annulus; and (3) an open single barrier completion with no additional downhole barriers. A reservoir model was used to assess the blowout flowing potential of SAGD well pairs. The probability of a blowout was estimated using fault tree analysis techniques. Risk was determined for various blowout scenarios, including blowouts during normal and workover operations, as well as blowouts through various flow paths. Total risk for each completion scenario was also determined at 3 different time periods within the production life of the well pair. The possible consequences of a blowout were assessed using quantitative consequence models. Results of the study showed that environmental and economic risks were much higher for the open completion technique. Higher risks were also associated with the earlier life of the completion strings. 20 refs., 3 tabs., 19 figs.

A quantitative flood risk analysis methodology for urban areas with integration of social research data

Science.gov (United States)

Escuder-Bueno, I.; Castillo-Rodríguez, J. T.; Zechner, S.; Jöbstl, C.; Perales-Momparler, S.; Petaccia, G.

2012-09-01

Risk analysis has become a top priority for authorities and stakeholders in many European countries, with the aim of reducing flooding risk, considering the population's needs and improving risk awareness. Within this context, two methodological pieces have been developed in the period 2009-2011 within the SUFRI project (Sustainable Strategies of Urban Flood Risk Management with non-structural measures to cope with the residual risk, 2nd ERA-Net CRUE Funding Initiative). First, the "SUFRI Methodology for pluvial and river flooding risk assessment in urban areas to inform decision-making" provides a comprehensive and quantitative tool for flood risk analysis. Second, the "Methodology for investigation of risk awareness of the population concerned" presents the basis to estimate current risk from a social perspective and identify tendencies in the way floods are understood by citizens. Outcomes of both methods are integrated in this paper with the aim of informing decision making on non-structural protection measures. The results of two case studies are shown to illustrate practical applications of this developed approach. The main advantage of applying the methodology herein presented consists in providing a quantitative estimation of flooding risk before and after investing in non-structural risk mitigation measures. It can be of great interest for decision makers as it provides rational and solid information.

The use of comparative risk assessment in decision making

International Nuclear Information System (INIS)

Chicken, J.C.; Hayns, M.R.; Tolley, B.

1989-01-01

This paper justifies: 1) Comparative risk assessment provides a way of establishing whether or not the risks associated with a novel proposal are likely to satisfy current norms. 2) Comparative risk assessment is an aid to decision making when for some reason there is inadequate quantitative data about the risks associated with a project. 3) One problem is that there is no single universally acceptable norm. Norms vary both with time and from activity to activity. The spread of acceptable norms spans at least two orders of magnitude. 4) For any comparative risk assessment to be considered more than a suggestion on how acceptable a risk is, the risks that are compared must be similar and located in similar cultural and geographical environments. 5) Ulitmately justification of the acceptability of a project must be based on data generated directly by the project itself and any opinion based on comparative evidence must be iteratively revised as direct hard evidence becomes available. 6) Comparative risk assessment has a useful role in presentations to the lay public about the acceptability of a particular risk. 7) There may be more problems in making a comparative assessment of risk acceptability in socio-political terms than in technical or economic terms. The central requirement that the comparison must be based on data from similar cultural backgrounds is often hard to satisfy in relation to socio-political considerations

Combination of qualitative and quantitative sources of knowledge for risk assessment in the framework of possibility theory

NARCIS (Netherlands)

Oussalah, M.; Newby, M.J.

2004-01-01

This paper focuses on a representation of system reliability in the framework of possibility theory. Particularly, given a (probabilistic) quantitative knowledge pertaining to the time to failure of a system (risk function) and some qualitative knowledge about the degree of pessimism and optimism of

HTGR containment design options: an application of probabilistic risk assessment

International Nuclear Information System (INIS)

1977-08-01

Through the use of probabilistic risk assessment (PRA), it is possible to quantitatively evaluate the radiological risk associated with a given reactor design and to place such risk into perspective with alternative designs. The merits are discussed for several containment alternatives for the HTGR from the viewpoints of economics and licensability, as well as public risk. The quantification of cost savings and public risk indicates that presently acceptable public risk can be maintained and cost savings of $40 million can result from use of a vented confinement for the HTGR

Review of fall risk assessment in geriatric populations using inertial sensors

OpenAIRE

Howcroft, Jennifer; Kofman, Jonathan; Lemaire, Edward D

2013-01-01

Background Falls are a prevalent issue in the geriatric population and can result in damaging physical and psychological consequences. Fall risk assessment can provide information to enable appropriate interventions for those at risk of falling. Wearable inertial-sensor-based systems can provide quantitative measures indicative of fall risk in the geriatric population. Methods Forty studies that used inertial sensors to evaluate geriatric fall risk were reviewed and pertinent methodological f...

Risk Assessment Method of UHV AC/DC Power System under Serious Disasters

Directory of Open Access Journals (Sweden)

Rishang Long

2016-12-01

Full Text Available Based on the theory of risk assessment, the risk assessment method for an ultra-high voltage (UHV AC/DC hybrid power system under severe disaster is studied. Firstly, considering the whole process of cascading failure, a fast failure probability calculation method is proposed, and the whole process risk assessment model is established considering the loss of both fault stage and recovery stage based on Monte Carlo method and BPA software. Secondly, the comprehensive evaluation index system is proposed from the aspects of power system structure, fault state and economic loss, and the quantitative assessment of system risk is carried out by an entropy weight model. Finally, the risk assessment of two UHV planning schemes are carried out and compared, which proves the effectiveness of the research work.

A Quantitative Measure For Evaluating Project Uncertainty Under Variation And Risk Effects

Directory of Open Access Journals (Sweden)

A. Chenarani

2017-10-01

Full Text Available The effects of uncertainty on a project and the risk event as the consequence of uncertainty are analyzed. The uncertainty index is proposed as a quantitative measure for evaluating the uncertainty of a project. This is done by employing entropy as the indicator of system disorder and lack of information. By employing this index, the uncertainty of each activity and its increase due to risk effects as well as project uncertainty changes as a function of time can be assessed. The results are implemented and analyzed for a small turbojet engine development project as the case study. The results of this study can be useful for project managers and other stakeholders for selecting the most effective risk management and uncertainty controlling method.

Probabilistic quantitative microbial risk assessment model of norovirus from wastewater irrigated vegetables in Ghana using genome copies and fecal indicator ratio conversion for estimating exposure dose.

Science.gov (United States)

Owusu-Ansah, Emmanuel de-Graft Johnson; Sampson, Angelina; Amponsah, Samuel K; Abaidoo, Robert C; Dalsgaard, Anders; Hald, Tine

2017-12-01

The need to replace the commonly applied fecal indicator conversions ratio (an assumption of 1:10 -5 virus to fecal indicator organism) in Quantitative Microbial Risk Assessment (QMRA) with models based on quantitative data on the virus of interest has gained prominence due to the different physical and environmental factors that might influence the reliability of using indicator organisms in microbial risk assessment. The challenges facing analytical studies on virus enumeration (genome copies or particles) have contributed to the already existing lack of data in QMRA modelling. This study attempts to fit a QMRA model to genome copies of norovirus data. The model estimates the risk of norovirus infection from the intake of vegetables irrigated with wastewater from different sources. The results were compared to the results of a corresponding model using the fecal indicator conversion ratio to estimate the norovirus count. In all scenarios of using different water sources, the application of the fecal indicator conversion ratio underestimated the norovirus disease burden, measured by the Disability Adjusted Life Years (DALYs), when compared to results using the genome copies norovirus data. In some cases the difference was >2 orders of magnitude. All scenarios using genome copies met the 10 -4 DALY per person per year for consumption of vegetables irrigated with wastewater, although these results are considered to be highly conservative risk estimates. The fecal indicator conversion ratio model of stream-water and drain-water sources of wastewater achieved the 10 -6 DALY per person per year threshold, which tends to indicate an underestimation of health risk when compared to using genome copies for estimating the dose. Copyright © 2017 Elsevier B.V. All rights reserved.

Integrated national-scale assessment of wildfire risk to human and ecological values

Science.gov (United States)

Matthew P. Thompson; David E. Calkin; Mark A. Finney; Alan A. Ager; Julie W. Gilbertson-Day

2011-01-01

The spatial, temporal, and social dimensions of wildfire risk are challenging U.S. federal land management agencies to meet societal needs while maintaining the health of the lands they manage. In this paper we present a quantitative, geospatial wildfire risk assessment tool, developed in response to demands for improved risk-based decision frameworks. The methodology...

Investment appraisal using quantitative risk analysis.

Science.gov (United States)

Johansson, Henrik

2002-07-01

Investment appraisal concerned with investments in fire safety systems is discussed. Particular attention is directed at evaluating, in terms of the Bayesian decision theory, the risk reduction that investment in a fire safety system involves. It is shown how the monetary value of the change from a building design without any specific fire protection system to one including such a system can be estimated by use of quantitative risk analysis, the results of which are expressed in terms of a Risk-adjusted net present value. This represents the intrinsic monetary value of investing in the fire safety system. The method suggested is exemplified by a case study performed in an Avesta Sheffield factory.

Farm to Fork Quantitative Risk Assessment of Listeria monocytogenes Contamination in Raw and Pasteurized Milk Cheese in Ireland.

Science.gov (United States)

Tiwari, Uma; Cummins, Enda; Valero, Antonio; Walsh, Des; Dalmasso, Marion; Jordan, Kieran; Duffy, Geraldine

2015-06-01

The objective of this study was to model and quantify the level of Listeria monocytogenes in raw milk cheese (RMc) and pasteurized milk cheese (PMc) from farm to fork using a Bayesian inference approach combined with a quantitative risk assessment. The modeling approach included a prediction of contamination arising from the farm environment as well from cross-contamination within the cheese-processing facility through storage and subsequent human exposure. The model predicted a high concentration of L. monocytogenes in contaminated RMc (mean 2.19 log10 CFU/g) compared to PMc (mean -1.73 log10 CFU/g). The mean probability of illness (P1 for low-risk population, LR) and (P2 for high-risk population, HR, e.g., immunocompromised) adult Irish consumers following exposure to contaminated cheese was 7 × 10(-8) (P1 ) and 9 × 10(-4) (P2 ) for RMc and 7 × 10(-10) (P1 ) and 8 × 10(-6) (P2 ) for PMc, respectively. In addition, the model was used to evaluate performance objectives at various stages, namely, the cheese making and ripening stages, and to set a food safety objective at the time of consumption. A scenario analysis predicted various probabilities of L. monocytogenes contamination along the cheese-processing chain for both RMc and PMc. The sensitivity analysis showed the critical factors for both cheeses were the serving size of the cheese, storage time, and temperature at the distribution stage. The developed model will allow food processors and policymakers to identify the possible routes of contamination along the cheese-processing chain and to reduce the risk posed to human health. © 2015 Society for Risk Analysis.

Can we (actually) assess global risk?

Science.gov (United States)

Di Baldassarre, Giuliano

2013-04-01

The evaluation of the dynamic interactions of the different components of global risk (e.g. hazard, exposure, vulnerability or resilience) is one of the main challenges in risk assessment and management. In state-of-the-art approaches for the analysis of risk, natural and socio-economic systems are typically treated separately by using different methods. In flood risk studies, for instance, physical scientists typically focus on the study of the probability of flooding (i.e. hazard), while social scientists mainly examine the exposure, vulnerability or resilience to flooding. However, these different components are deeply interconnected. Changes in flood hazard might trigger changes in vulnerability, and vice versa. A typical example of these interactions is the so-called "levee effect", whereby heightening levees to reduce the probability of flooding often leads to increase the potential adverse consequences of flooding as people often perceive that flood risk was completely eliminated once the levee was raised. These interconnections between the different components of risk remain largely unexplored and poorly understood. This lack of knowledge is of serious concern as it limits our ability to plan appropriate risk prevention measures. To design flood control structures, for example, state-of-the-art models can indeed provide quantitative assessments of the corresponding risk reduction associated to the lower probability of flooding. Nevertheless, current methods cannot estimate how, and to what extent, such a reduction might trigger a future increase of the potential adverse consequences of flooding (the aforementioned "levee effect"). Neither can they evaluate how the latter might (in turn) lead to the requirement of additional flood control structures. Thus, while many progresses have been made in the static assessment of flood risk, more inter-disciplinary research is required for the development of methods for dynamic risk assessment, which is very much

Establishing indices for groundwater contamination risk assessment in the vicinity of hazardous waste landfills in China

International Nuclear Information System (INIS)

Li Ying; Li Jinhui; Chen Shusheng; Diao Weihua

2012-01-01

Groundwater contamination by leachate is the most damaging environmental impact over the entire life of a hazardous waste landfill (HWL). With the number of HWL facilities in China rapidly increasing, and considering the poor status of environmental risk management, it is imperative that effective environmental risk management methods be implemented. A risk assessment indices system for HWL groundwater contamination is here proposed, which can simplify the risk assessment procedure and make it more user-friendly. The assessment framework and indices were drawn from five aspects: source term, underground media, leachate properties, risk receptors and landfill management quality, and a risk assessment indices system consisting of 38 cardinal indicators was established. Comparison with multimedia models revealed that the proposed indices system was integrated and quantitative, that input data for it could be easily collected, and that it could be widely used for environmental risk assessment (ERA) in China. - Highlights: ► No comprehensive environmental risk assessment method for hazardous waste management is proposed in China. ► An assessment indices system is established for groundwater contamination in the vicinity of hazardous waste landfill. ► All indicators are quantitative and applicable in China. - Capsule: This research identified critical indices and established a system for environmental risk assessment for groundwater contamination in the vicinity of HWLs in China.

Participatory Risk Assessment for Environmental Decision-Making

International Nuclear Information System (INIS)

Homan, Jacqueline; Petts, Judith

2001-01-01

Recent research, discussion and practice in the role environmental decision-making as an integral part of a democratic society have resulted in legislation, policy and guidance that encourage, and indeed may require, greater participation. The focus of this research paper is to explore these participatory ideas in the context of environmental risk assessment. Participation methods have generic application. However, the importance of fitting method to purpose requires that different contexts and issues relative to the objectives be addressed. In relation to environmental risk assessment these issues include: the complexity of risk issues per se; the inherent uncertainty that dominates any risk assessment; the quantitative nature of many risk assessments and the difficulty of dealing with low probability-high consequence outconies; the possibility of controversy in relation to decisions involving risk and thus the careful attention needed to the process and identification of participants; the traditional role and culture of experts in risk decisions and the challenge of reconciling this with the role of lay knowledge and the potential for the public to act as quality assurers in the risk decision process; the tendency for people to need reassurance when confronted with risk, even during a participation process; the need to acknowledge the public's ability to deal with complex technical issues and the need for information and data to respond to their questions, and the fact that 'risk' per se will often not be the only issue of public concern. The contributions to the risk debate from the social sciences are having considerable influence on the practice of environmental decision-making. Calls for increased stakeholder involvement in risk decisions are requiring greater access to and engagement with environmental risk assessments. Mechanisms for this level of involvement, however, are not well defined. For these aspirational calls to be realised in practice, decision

Participatory Risk Assessment for Environmental Decision-Making

Energy Technology Data Exchange (ETDEWEB)

Homan, Jacqueline; Petts, Judith [Univ. of Birmingham (United Kingdom). Centre for Environmental Research and Training; Pollard, Simon; Twigger-Ross, Clare [National Centre for Risk Analysis and Options Appraisal, London (United Kingdom)

2001-07-01

Recent research, discussion and practice in the role environmental decision-making as an integral part of a democratic society have resulted in legislation, policy and guidance that encourage, and indeed may require, greater participation. The focus of this research paper is to explore these participatory ideas in the context of environmental risk assessment. Participation methods have generic application. However, the importance of fitting method to purpose requires that different contexts and issues relative to the objectives be addressed. In relation to environmental risk assessment these issues include: the complexity of risk issues per se; the inherent uncertainty that dominates any risk assessment; the quantitative nature of many risk assessments and the difficulty of dealing with low probability-high consequence outconies; the possibility of controversy in relation to decisions involving risk and thus the careful attention needed to the process and identification of participants; the traditional role and culture of experts in risk decisions and the challenge of reconciling this with the role of lay knowledge and the potential for the public to act as quality assurers in the risk decision process; the tendency for people to need reassurance when confronted with risk, even during a participation process; the need to acknowledge the public's ability to deal with complex technical issues and the need for information and data to respond to their questions, and the fact that 'risk' per se will often not be the only issue of public concern. The contributions to the risk debate from the social sciences are having considerable influence on the practice of environmental decision-making. Calls for increased stakeholder involvement in risk decisions are requiring greater access to and engagement with environmental risk assessments. Mechanisms for this level of involvement, however, are not well defined. For these aspirational calls to be realised in

Potential application of quantitative microbiological risk assessment techniques to an aseptic-UHT process in the food industry.

Science.gov (United States)

Pujol, Laure; Albert, Isabelle; Johnson, Nicholas Brian; Membré, Jeanne-Marie

2013-04-01

Aseptic ultra-high-temperature (UHT)-type processed food products (e.g., milk or soup) are ready to eat products which are consumed extensively globally due to a combination of their comparative high quality and long shelf life, with no cold chain or other preservation requirements. Due to the inherent microbial vulnerability of aseptic-UHT product formulations, the safety and stability-related performance objectives (POs) required at the end of the manufacturing process are the most demanding found in the food industry. The key determinants to achieving sterility, and which also differentiates aseptic-UHT from in-pack sterilised products, are the challenges associated with the processes of aseptic filling and sealing. This is a complex process that has traditionally been run using deterministic or empirical process settings. Quantifying the risk of microbial contamination and recontamination along the aseptic-UHT process, using the scientifically based process quantitative microbial risk assessment (QMRA), offers the possibility to improve on the currently tolerable sterility failure rate (i.e., 1 defect per 10,000 units). In addition, benefits of applying QMRA are (i) to implement process settings in a transparent and scientific manner; (ii) to develop a uniform common structure whatever the production line, leading to a harmonisation of these process settings, and; (iii) to bring elements of a cost-benefit analysis of the management measures. The objective of this article is to explore how QMRA techniques and risk management metrics may be applied to aseptic-UHT-type processed food products. In particular, the aseptic-UHT process should benefit from a number of novel mathematical and statistical concepts that have been developed in the field of QMRA. Probabilistic techniques such as Monte Carlo simulation, Bayesian inference and sensitivity analysis, should help in assessing the compliance with safety and stability-related POs set at the end of the manufacturing

A probabilistic method for computing quantitative risk indexes from medical injuries compensation claims.

Science.gov (United States)

Dalle Carbonare, S; Folli, F; Patrini, E; Giudici, P; Bellazzi, R

2013-01-01

The increasing demand of health care services and the complexity of health care delivery require Health Care Organizations (HCOs) to approach clinical risk management through proper methods and tools. An important aspect of risk management is to exploit the analysis of medical injuries compensation claims in order to reduce adverse events and, at the same time, to optimize the costs of health insurance policies. This work provides a probabilistic method to estimate the risk level of a HCO by computing quantitative risk indexes from medical injury compensation claims. Our method is based on the estimate of a loss probability distribution from compensation claims data through parametric and non-parametric modeling and Monte Carlo simulations. The loss distribution can be estimated both on the whole dataset and, thanks to the application of a Bayesian hierarchical model, on stratified data. The approach allows to quantitatively assessing the risk structure of the HCO by analyzing the loss distribution and deriving its expected value and percentiles. We applied the proposed method to 206 cases of injuries with compensation requests collected from 1999 to the first semester of 2007 by the HCO of Lodi, in the Northern part of Italy. We computed the risk indexes taking into account the different clinical departments and the different hospitals involved. The approach proved to be useful to understand the HCO risk structure in terms of frequency, severity, expected and unexpected loss related to adverse events.

Quantitative structure-activity relationships for predicting potential ecological hazard of organic chemicals for use in regulatory risk assessments.

Science.gov (United States)

Comber, Mike H I; Walker, John D; Watts, Chris; Hermens, Joop

2003-08-01

The use of quantitative structure-activity relationships (QSARs) for deriving the predicted no-effect concentration of discrete organic chemicals for the purposes of conducting a regulatory risk assessment in Europe and the United States is described. In the United States, under the Toxic Substances Control Act (TSCA), the TSCA Interagency Testing Committee and the U.S. Environmental Protection Agency (U.S. EPA) use SARs to estimate the hazards of existing and new chemicals. Within the Existing Substances Regulation in Europe, QSARs may be used for data evaluation, test strategy indications, and the identification and filling of data gaps. To illustrate where and when QSARs may be useful and when their use is more problematic, an example, methyl tertiary-butyl ether (MTBE), is given and the predicted and experimental data are compared. Improvements needed for new QSARs and tools for developing and using QSARs are discussed.

Definition of a short-cut methodology for assessing earthquake-related Na-Tech risk

International Nuclear Information System (INIS)

Busini, Valentina; Marzo, Enrico; Callioni, Andrea; Rota, Renato

2011-01-01

Highlights: → In industrial sites located in natural hazard-prone areas technological accidents may be triggered by natural events, generating the so-called Na-Tech accidents. → In this paper, a qualitative screening methodology for assessing the earthquake Na-Tech risk has been developed with the aim of identifying which situations deserve a much more expensive Quantitative Risk Analysis. → The simple procedure developed, which summarizes in a suitable Key Hazard Indicator the Na-Tech risk level, has been validated by comparing its results with those of some Quantitative Risk Analyses involving also Na-Tech events and previously presented in the literature. - Abstract: Na-Tech (Natural and Technological) refers to industrial accidents triggered by natural events such as storms, earthquakes, flooding, and lightning. Herein, a qualitative methodology for the initial assessment of earthquake Na-Tech risk has been developed as a screening tool to identify which situations require a much more expensive Quantitative Risk Analysis (QRA). The proposed methodology, through suitable Key Hazard Indicators (KHIs), identifies the Na-Tech risk level associated with a given situation (i.e., a process plant located in a given territory), using the Analytical Hierarchy Process as a multi-criteria decision tool for the evaluation of such KHIs. The developed methodology was validated by comparing its computational results with QRA results that involved Na-Tech events previously presented in literature.

A quantitative flood risk analysis methodology for urban areas with integration of social research data

Directory of Open Access Journals (Sweden)

I. Escuder-Bueno

2012-09-01

Full Text Available Risk analysis has become a top priority for authorities and stakeholders in many European countries, with the aim of reducing flooding risk, considering the population's needs and improving risk awareness. Within this context, two methodological pieces have been developed in the period 2009–2011 within the SUFRI project (Sustainable Strategies of Urban Flood Risk Management with non-structural measures to cope with the residual risk, 2nd ERA-Net CRUE Funding Initiative. First, the "SUFRI Methodology for pluvial and river flooding risk assessment in urban areas to inform decision-making" provides a comprehensive and quantitative tool for flood risk analysis. Second, the "Methodology for investigation of risk awareness of the population concerned" presents the basis to estimate current risk from a social perspective and identify tendencies in the way floods are understood by citizens. Outcomes of both methods are integrated in this paper with the aim of informing decision making on non-structural protection measures. The results of two case studies are shown to illustrate practical applications of this developed approach. The main advantage of applying the methodology herein presented consists in providing a quantitative estimation of flooding risk before and after investing in non-structural risk mitigation measures. It can be of great interest for decision makers as it provides rational and solid information.

Computer codes to assess risks from nuclear power plants with LWR's

International Nuclear Information System (INIS)

Alonso, A.; Blanco, J.; Francia, L.; Gallego, E.; Morales, L.; Ortega, P.; Torres, C.

1986-01-01

The codes used to quantify risks from nuclear power plants are described. For QRA level 1 (quantitative risk assessment) qualitative and quantitative codes are described. Codes to estimate uncertainties, importance and dependent failures are also included. For QRA-level 2, the most important codes dealing with thermohydraulics, molten core and aerosols behaviour are described. For QRA-level 3 the list includes integrated as well as separate models. Only light water reactors are considered. The presentation is general but the authors describe with more detail those codes they are more familiar with or the ones they have created through their research effort. (author)

Rapid Response Risk Assessment in New Project Development

Science.gov (United States)

Graber, Robert R.

2010-01-01

A capability for rapidly performing quantitative risk assessments has been developed by JSC Safety and Mission Assurance for use on project design trade studies early in the project life cycle, i.e., concept development through preliminary design phases. A risk assessment tool set has been developed consisting of interactive and integrated software modules that allow a user/project designer to assess the impact of alternative design or programmatic options on the probability of mission success or other risk metrics. The risk and design trade space includes interactive options for selecting parameters and/or metrics for numerous design characteristics including component reliability characteristics, functional redundancy levels, item or system technology readiness levels, and mission event characteristics. This capability is intended for use on any project or system development with a defined mission, and an example project will used for demonstration and descriptive purposes, e.g., landing a robot on the moon. The effects of various alternative design considerations and their impact of these decisions on mission success (or failure) can be measured in real time on a personal computer. This capability provides a high degree of efficiency for quickly providing information in NASA s evolving risk-based decision environment

Quantitative risk assessment for Escherichia coli O157:H7 in frozen ground beef patties consumed by young children in French households.

Science.gov (United States)

Delignette-Muller, M L; Cornu, M

2008-11-30

A quantitative risk assessment for Escherichia coli O157:H7 in frozen ground beef patties consumed by children under 10 years of age in French households was conducted by a national study group describing an outbreak which occurred in France in 2005. Our exposure assessment model incorporates results from French surveys on consumption frequency of ground beef patties, serving size and consumption preference, microbial destruction experiments and microbial counts on patties sampled from the industrial batch which were responsible for the outbreak. Two different exposure models were proposed, respectively for children under the age of 5 and for children between 5 and 10 years. For each of these two age groups, a single-hit dose-response model was proposed to describe the probability of hemolytic and uremic syndrome (HUS) as a function of the ingested dose. For each group, the single parameter of this model was estimated by Bayesian inference, using the results of the exposure assessment and the epidemiological data collected during the outbreak. Results show that children under 5 years of age are roughly 5 times more susceptible to the pathogen than children over 5 years. Exposure and dose-response models were used in a scenario analysis in order to validate the use of the model and to propose appropriate guidelines in order to prevent new outbreaks. The impact of the cooking preference was evaluated, showing that only a well-done cooking notably reduces the HUS risk, without annulling it. For each age group, a relation between the mean individual HUS risk per serving and the contamination level in a ground beef batch was proposed, as a tool to help French risk managers.

Quantitative weight of evidence assessment of higher tier studies on the toxicity and risks of neonicotinoids in honeybees. 3. Clothianidin.

Science.gov (United States)

Solomon, Keith R; Stephenson, Gladys L

2017-01-01

A quantitative weight of evidence (QWoE) methodology was used to assess higher tier studies on the effects of clothianidin (CTD) on honeybees. Assessment endpoints were population size and viability of commercially managed bees and quantity of hive products. A colony-level no-observed-adverse effect concentration (NOAEC) of 25 µg CTD/kg syrup, equivalent to an oral no-observed-adverse effect-dose (NOAED) of 7.3 ng/bee/d for all responses measured. Based on a NOAEC of 19.7 µg/kg pollen, the NOAED for honeybee larvae was 2.4 ng/bee larva/d. For exposures via dust, a no-observed-adverse effect rate of 4 g CTD/ha was used to assess relevance of exposures via deposition of dust. The overall weight of evidence suggested that there is minimal risk to honeybees from exposure to CTD from its use as a seed treatment. For exposures via dust, dust/seed and dust/foliar applications, there were no exposures greater than the NOAED for CTD in nectar and pollen, indicating a de minimis risk to honeybees when the route of exposure was via uptake in plants. Analysis of effect studies in the field indicated a consistent lack of relevant effects, regardless of the way CTD was applied. For exposures via dust, there were no adverse effects because of these applications and there were no exposures greater than the NOAED for CTD in nectar and pollen. The overall weight of evidence based on many studies indicated no adverse effects on colony viability or survival of the colony. Thus, the overall conclusion is that clothianidin, as currently used in good agricultural practices, does not present a significant risk to honeybees at the level of the colony.

Thrombotic risk assessment in APS: the Global APS Score (GAPSS).

Science.gov (United States)

Sciascia, S; Bertolaccini, M L

2014-10-01

Recently, we developed a risk score for antiphospholipid syndrome (APS) (Global APS Score or GAPSS). This score derived from the combination of independent risk factors for thrombosis and pregnancy loss, taking into account the antiphospholipid antibodies (aPL) profile (criteria and non-criteria aPL), the conventional cardiovascular risk factors, and the autoimmune antibodies profile. We demonstrate that risk profile in APS can be successfully assessed, suggesting that GAPSS can be a potential quantitative marker of APS-related clinical manifestations. © The Author(s) 2014 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav.

BBN based Quantitative Assessment of Software Design Specification

International Nuclear Information System (INIS)

Eom, Heung-Seop; Park, Gee-Yong; Kang, Hyun-Gook; Kwon, Kee-Choon; Chang, Seung-Cheol

2007-01-01

Probabilistic Safety Assessment (PSA), which is one of the important methods in assessing the overall safety of a nuclear power plant (NPP), requires quantitative reliability information of safety-critical software, but the conventional reliability assessment methods can not provide enough information for PSA of a NPP. Therefore current PSA which includes safety-critical software does not usually consider the reliability of the software or uses arbitrary values for it. In order to solve this situation this paper proposes a method that can produce quantitative reliability information of safety-critical software for PSA by making use of Bayesian Belief Networks (BBN). BBN has generally been used to model an uncertain system in many research fields including the safety assessment of software. The proposed method was constructed by utilizing BBN which can combine the qualitative and the quantitative evidence relevant to the reliability of safety critical software. The constructed BBN model can infer a conclusion in a formal and a quantitative way. A case study was carried out with the proposed method to assess the quality of software design specification (SDS) of safety-critical software that will be embedded in a reactor protection system. The intermediate V and V results of the software design specification were used as inputs to the BBN model

Quantitative Risk Assessment of Patient Manual Handling in Wards of One of the Hospitals of Tehran using MAPO Method, Iran

Directory of Open Access Journals (Sweden)

Sajad Ataei

2017-05-01

Full Text Available Background and Objectives: Manual handling of disabled patients is one of the important and effective factors in acute low back pain among exposed nurses. The present study was conducted with the objective of quantitative risk assessment of patient manual handling among nurses in wards of one of the hospitals in Tehran using MAPO method. Methods: The present study was conducted as an analytical-cross-sectional study in 26 wards of one of the hospitals in Tehran city. Samples were selected by census method from nurses and paramedics of different wards of hospital. Data collection was performed using demographic information and MAPO checklist. Results: The highest score of MAPO were, respectively, related to wards of DI clinic (score, 14.7, men orthopedic (score, 6.3, and general operating room (score, 57. 53.8% of hospital wards were at the level 2 corrective action, which indicated that the risk of musculoskeletal disorder is 2.4 times higher than level 1 corrective action. Conclusion: Given that the proportion of disabled patient in cooperation and/or partial cooperation, lifting tools, auxiliary, wheelchair, and training have the most role among risk factors for above-mentioned wards, increasing the number of human resources and wheelchair, use of lifting and auxiliary tools and training reduce MAPO score and consequently the risk of musculoskeletal disorders.

Considerations on comprehensive risk assessment and mitigation planning of volcanic ash-fall

International Nuclear Information System (INIS)

Toshida, Kiyoshi

2010-01-01

Volcanic ash-fall is inevitable hazard throughout Japan, and causes wide range of effects due to its physical and chemical properties. Nuclear power plants in Japan face the necessity to assess the risk from volcanic ash-fall. Risk assessment of the volcanic ash-fall should include engineering solution and mitigation planning as well as the ash-fall hazard. This report points out the characteristics for reducing the various effects of volcanic ash-fall as follows. Large-scale eruptions produce prominent volcanic ash-falls that can approach power plants at a great distance. Aftermath hazards of ash-fall events, such as remobilization of fine ash particles and generation of lahars, require further assessments. The kind and extent of damages becomes greater whenever ash is wet. Wet ash requires separate assessments in contrast to dry ash. The mitigation and recovery measures at power plants involve quick cleanup operations of volcanic ash. Those operations should be prepared through comprehensive risk assessment, and by cooperation with authorities, during pre-eruption repose period. The comprehensive assessment for volcanic ash-fall hazards, however, has yet to be conducted. Development of risk communication method may result in increased implementation mitigation planning. Numerical analysis of the ash-fall hazards provides quantitative data on particle motions that can be used in the risk assessment. In order to implement the quantitative assessment method, the verification on the effect of ambient air condition to the altitude of volcanic ash cloud is necessary. We need to develop a three-dimensional model of volcanic ash cloud, and calculate motions of ash clouds under multiple conditions of ambient air. (author)

Comparative measurement and quantitative risk assessment of alcohol consumption through wastewater-based epidemiology: An international study in 20 cities

DEFF Research Database (Denmark)

Ryu, Yeonsuk; Barceló, Damià; Barron, Leon P.

2016-01-01

Quantitative measurement of drug consumption biomarkers in wastewater can provide objective information on community drug use patterns and trends. This study presents the measurement of alcohol consumption in 20 cities across 11 countries through the use of wastewater-based epidemiology (WBE...... consumption biomarker, ethyl sulfate (EtS) was determined by liquid chromatography coupled to tandem mass spectrometry. The EtS concentrations were used for estimation of per capita alcohol consumption in each city, which was further compared with international reports and applied for risk assessment by MOE....... The average per capita consumption in 20 cities ranged between 6.4 and 44.3. L/day/1000 inhabitants. An increase in alcohol consumption during the weekend occurred in all cities, however the level of this increase was found to differ. In contrast to conventional data (sales statistics and interviews), WBE...

Navigational Traffic Conflict Technique: A Proactive Approach to Quantitative Measurement of Collision Risks in Port Waters

Science.gov (United States)

Debnath, Ashim Kumar; Chin, Hoong Chor

Navigational safety analysis relying on collision statistics is often hampered because of the low number of observations. A promising alternative approach that overcomes this problem is proposed in this paper. By analyzing critical vessel interactions this approach proactively measures collision risk in port waters. The proposed method is illustrated for quantitative measurement of collision risks in Singapore port fairways, and validated by examining correlations between the measured risks with those perceived by pilots. This method is an ethically appealing alternative to the collision-based analysis for fast, reliable and effective safety assessment, thus possessing great potential for managing collision risks in port waters.

Assessing the risk posed by natural hazards to infrastructures

Science.gov (United States)

Eidsvig, Unni Marie K.; Kristensen, Krister; Vidar Vangelsten, Bjørn

2017-03-01

This paper proposes a model for assessing the risk posed by natural hazards to infrastructures, with a focus on the indirect losses and loss of stability for the population relying on the infrastructure. The model prescribes a three-level analysis with increasing level of detail, moving from qualitative to quantitative analysis. The focus is on a methodology for semi-quantitative analyses to be performed at the second level. The purpose of this type of analysis is to perform a screening of the scenarios of natural hazards threatening the infrastructures, identifying the most critical scenarios and investigating the need for further analyses (third level). The proposed semi-quantitative methodology considers the frequency of the natural hazard, different aspects of vulnerability, including the physical vulnerability of the infrastructure itself, and the societal dependency on the infrastructure. An indicator-based approach is applied, ranking the indicators on a relative scale according to pre-defined ranking criteria. The proposed indicators, which characterise conditions that influence the probability of an infrastructure malfunctioning caused by a natural event, are defined as (1) robustness and buffer capacity, (2) level of protection, (3) quality/level of maintenance and renewal, (4) adaptability and quality of operational procedures and (5) transparency/complexity/degree of coupling. Further indicators describe conditions influencing the socio-economic consequences of the infrastructure malfunctioning, such as (1) redundancy and/or substitution, (2) cascading effects and dependencies, (3) preparedness and (4) early warning, emergency response and measures. The aggregated risk estimate is a combination of the semi-quantitative vulnerability indicators, as well as quantitative estimates of the frequency of the natural hazard, the potential duration of the infrastructure malfunctioning (e.g. depending on the required restoration effort) and the number of users of

Risk assessment for construction projects of transport infrastructure objects

Science.gov (United States)

Titarenko, Boris

2017-10-01

The paper analyzes and compares different methods of risk assessment for construction projects of transport objects. The management of such type of projects demands application of special probabilistic methods due to large level of uncertainty of their implementation. Risk management in the projects requires the use of probabilistic and statistical methods. The aim of the work is to develop a methodology for using traditional methods in combination with robust methods that allow obtaining reliable risk assessments in projects. The robust approach is based on the principle of maximum likelihood and in assessing the risk allows the researcher to obtain reliable results in situations of great uncertainty. The application of robust procedures allows to carry out a quantitative assessment of the main risk indicators of projects when solving the tasks of managing innovation-investment projects. Calculation of damage from the onset of a risky event is possible by any competent specialist. And an assessment of the probability of occurrence of a risky event requires the involvement of special probabilistic methods based on the proposed robust approaches. Practice shows the effectiveness and reliability of results. The methodology developed in the article can be used to create information technologies and their application in automated control systems for complex projects.

Risk Assessment for Mobile Systems Through a Multilayered Hierarchical Bayesian Network.

Science.gov (United States)

Li, Shancang; Tryfonas, Theo; Russell, Gordon; Andriotis, Panagiotis

2016-08-01

Mobile systems are facing a number of application vulnerabilities that can be combined together and utilized to penetrate systems with devastating impact. When assessing the overall security of a mobile system, it is important to assess the security risks posed by each mobile applications (apps), thus gaining a stronger understanding of any vulnerabilities present. This paper aims at developing a three-layer framework that assesses the potential risks which apps introduce within the Android mobile systems. A Bayesian risk graphical model is proposed to evaluate risk propagation in a layered risk architecture. By integrating static analysis, dynamic analysis, and behavior analysis in a hierarchical framework, the risks and their propagation through each layer are well modeled by the Bayesian risk graph, which can quantitatively analyze risks faced to both apps and mobile systems. The proposed hierarchical Bayesian risk graph model offers a novel way to investigate the security risks in mobile environment and enables users and administrators to evaluate the potential risks. This strategy allows to strengthen both app security as well as the security of the entire system.

Lessons learned from first generation nuclear plant probabalistic risk assessments

International Nuclear Information System (INIS)

Garrick, B.J.

1984-01-01

The paper by Garrick summarizes the state-of-the-art in what are perhaps the most archetypical probabilistic risk assessments (PRAs). Because of its unique regulatory environment and because of the high levels of perceived (not necessarily actual) risk, the nuclear industry more than any other has been concerned with quantitative risk analysis. Garrick's paper summarizes the lessons learned from ten PRA's conducted in the nuclear industry, including six that can be characterized as full-scope risk studies. Most of the quantitative data, though, came from two especially thorough studies done for the Zion and Indian Point power plants, operated by Commonwealth Edison and Consolidated Edison respectively. The principal conclusions of the Garrick survey are that the public risk (from radiation release) is now known to be very small for commercial nuclear power plants, but that the risk to utilities (from core damage) is somewhat larger. Significant radiation releases require both core meltdown -- an event occurring only about once every 10,000 reactor-years -- and containment failure, occurring only about once in every hundred meltdowns

Quantitative rock-fall hazard and risk assessment for Yosemite Valley, Yosemite National Park, California

Science.gov (United States)

Stock, Greg M.; Luco, Nicolas; Collins, Brian D.; Harp, Edwin L.; Reichenbach, Paola; Frankel, Kurt L.

2014-01-01

Rock falls are common in Yosemite Valley, California, posing substantial hazard and risk to the approximately four million annual visitors to Yosemite National Park. Rock falls in Yosemite Valley over the past few decades have damaged structures and caused injuries within developed regions located on or adjacent to talus slopes highlighting the need for additional investigations into rock-fall hazard and risk. This assessment builds upon previous investigations of rock-fall hazard and risk in Yosemite Valley and focuses on hazard and risk to structures posed by relatively frequent fragmental-type rock falls as large as approximately 100,000 (cubic meters) in volume.

Assessment of yellow fever epidemic risk: an original multi-criteria modeling approach.

Directory of Open Access Journals (Sweden)

Sylvie Briand

Full Text Available BACKGROUND: Yellow fever (YF virtually disappeared in francophone West African countries as a result of YF mass vaccination campaigns carried out between 1940 and 1953. However, because of the failure to continue mass vaccination campaigns, a resurgence of the deadly disease in many African countries began in the early 1980s. We developed an original modeling approach to assess YF epidemic risk (vulnerability and to prioritize the populations to be vaccinated. METHODS AND FINDINGS: We chose a two-step assessment of vulnerability at district level consisting of a quantitative and qualitative assessment per country. Quantitative assessment starts with data collection on six risk factors: five risk factors associated with "exposure" to virus/vector and one with "susceptibility" of a district to YF epidemics. The multiple correspondence analysis (MCA modeling method was specifically adapted to reduce the five exposure variables to one aggregated exposure indicator. Health districts were then projected onto a two-dimensional graph to define different levels of vulnerability. Districts are presented on risk maps for qualitative analysis in consensus groups, allowing the addition of factors, such as population migrations or vector density, that could not be included in MCA. The example of rural districts in Burkina Faso show five distinct clusters of risk profiles. Based on this assessment, 32 of 55 districts comprising over 7 million people were prioritized for preventive vaccination campaigns. CONCLUSION: This assessment of yellow fever epidemic risk at the district level includes MCA modeling and consensus group modification. MCA provides a standardized way to reduce complexity. It supports an informed public health decision-making process that empowers local stakeholders through the consensus group. This original approach can be applied to any disease with documented risk factors.

Taking the Risk Out of Risk Assessment

Science.gov (United States)

2005-01-01

The ability to understand risks and have the right strategies in place when risky events occur is essential in the workplace. More and more organizations are being confronted with concerns over how to measure their risks or what kind of risks they can take when certain events transpire that could have a negative impact. NASA is one organization that faces these challenges on a daily basis, as effective risk management is critical to the success of its missions especially the Space Shuttle missions. On July 29, 1996, former NASA Administrator Daniel Goldin charged NASA s Office of Safety and Mission Assurance with developing a probabilistic risk assessment (PRA) tool to support decisions on the funding of Space Shuttle upgrades. When issuing the directive, Goldin said, "Since I came to NASA [in 1992], we've spent billions of dollars on Shuttle upgrades without knowing how much they improve safety. I want a tool to help base upgrade decisions on risk." Work on the PRA tool began immediately. The resulting prototype, the Quantitative Risk Assessment System (QRAS) Version 1.0, was jointly developed by NASA s Marshall Space Flight Center, its Office of Safety and Mission Assurance, and researchers at the University of Maryland. QRAS software automatically expands the reliability logic models of systems to evaluate the probability of highly detrimental outcomes occurring in complex systems that are subject to potential accident scenarios. Even in its earliest forms, QRAS was used to begin PRA modeling of the Space Shuttle. In parallel, the development of QRAS continued, with the goal of making it a world-class tool, one that was especially suited to NASA s unique needs. From the beginning, an important conceptual goal in the development of QRAS was for it to help bridge the gap between the professional risk analyst and the design engineer. In the past, only the professional risk analyst could perform, modify, use, and perhaps even adequately understand PRA. NASA wanted

Human-Associated Fecal Quantitative Polymerase Chain ReactionMeasurements and Simulated Risk of Gastrointestinal Illness in Recreational Waters Contaminated with Raw Sewage

Science.gov (United States)

We used quantitative microbial risk assessment (QMRA) to estimate the risk of gastrointestinal (GI) illness associated with swimming in recreational waters containing different concentrations of human-associated fecal qPCR markers from raw sewage– HF183 and HumM2. The volume/volu...

A New Approach to Feasibility Risk Assessment within Transport Infrastructure Appraisal

DEFF Research Database (Denmark)

Salling, Kim Bang

2013-01-01

This paper introduces a new approach of applying feasibility risk assessment within transport project infrastructure appraisal. The procedure is based upon quantitative risk analysis and Monte Carlo simulation in combination with conventional cost-benefit analysis converting deterministic benefit...... are, hereby, often basing their decisions on wrongful material. The presented approach to transport infrastructure appraisal is to include uncertainties and risks in the evaluation. Correspondingly, the handling of uncertainties and risk within transport project assessment are often made up...... by sensitivity tests producing deterministically based output values. Research has proven that traditional sensitivity analysis seldomnly captures the total variability especially as concerns the costs and demands estimated in the pre-stage of the evaluation. Therefore, this paper introduces an approach...

Reinforcement of qualitative risk assessment proposals from computer science

International Nuclear Information System (INIS)

Friedlhuber, T.; Hibti, M.; Rauzy, A.

2013-01-01

During the last decade a lot of research has been made to evaluate concepts and methos of quantitative risk assessment in order to predict hazards more precisely. Nevertheless, the occurrence of new catastrophes like the Indonesian Tsunami in 2004, the Deepwater Horizon accident in 2010 or recently the Fukushima accidents in 2011 raise the question whether we may underestimate some natural limits of annotative risk assessment or even mistake its significance. Especially in the case of very unlikely events, in combination with uncertainty and severe consequences, may be we would do better to concentrate more on understanding risk than on calculating probability values. In this paper we apply progresses, made in the field of computer science, to tools and modelling concepts used in risk assessment. Regarding computer science, we point out now concepts, that may improve the quality of risk models and the process of model engineering. The goal is to reinforce the importance of qualitative risk assessment with the help of sophisticated tools and modelling. Qualitative risk assessment aims to understand risk and therefore reflects the initial idea of risk assessment. Risk understanding requires understanding systems and relations of components. It is fundamental to comprehend the meaning of components in fault- and event trees, to retrace all applied modifications and to highlight critical aspects. It is important how PSA models are visualized, documented, navigated, how results are presented and how model maintenance, integration and version control are performed. Also, the conjoint usage of different type of models (for example PSA models together with event sequence diagrams) can contribute to quality assurance. We present new concepts for various kind of problems. (author)

The Next Generation of Risk Assessment Multi-Year Study—Highlights of Findings, Applications to Risk Assessment, and Future Directions

Science.gov (United States)

Cote, Ila; Andersen, Melvin E.; Ankley, Gerald T.; Barone, Stanley; Birnbaum, Linda S.; Boekelheide, Kim; Bois, Frederic Y.; Burgoon, Lyle D.; Chiu, Weihsueh A.; Crawford-Brown, Douglas; Crofton, Kevin M.; DeVito, Michael; Devlin, Robert B.; Edwards, Stephen W.; Guyton, Kathryn Z.; Hattis, Dale; Judson, Richard S.; Knight, Derek; Krewski, Daniel; Lambert, Jason; Maull, Elizabeth Anne; Mendrick, Donna; Paoli, Gregory M.; Patel, Chirag Jagdish; Perkins, Edward J.; Poje, Gerald; Portier, Christopher J.; Rusyn, Ivan; Schulte, Paul A.; Simeonov, Anton; Smith, Martyn T.; Thayer, Kristina A.; Thomas, Russell S.; Thomas, Reuben; Tice, Raymond R.; Vandenberg, John J.; Villeneuve, Daniel L.; Wesselkamper, Scott; Whelan, Maurice; Whittaker, Christine; White, Ronald; Xia, Menghang; Yauk, Carole; Zeise, Lauren; Zhao, Jay; DeWoskin, Robert S.

2016-01-01

Background: The Next Generation (NexGen) of Risk Assessment effort is a multi-year collaboration among several organizations evaluating new, potentially more efficient molecular, computational, and systems biology approaches to risk assessment. This article summarizes our findings, suggests applications to risk assessment, and identifies strategic research directions. Objective: Our specific objectives were to test whether advanced biological data and methods could better inform our understanding of public health risks posed by environmental exposures. Methods: New data and methods were applied and evaluated for use in hazard identification and dose–response assessment. Biomarkers of exposure and effect, and risk characterization were also examined. Consideration was given to various decision contexts with increasing regulatory and public health impacts. Data types included transcriptomics, genomics, and proteomics. Methods included molecular epidemiology and clinical studies, bioinformatic knowledge mining, pathway and network analyses, short-duration in vivo and in vitro bioassays, and quantitative structure activity relationship modeling. Discussion: NexGen has advanced our ability to apply new science by more rapidly identifying chemicals and exposures of potential concern, helping characterize mechanisms of action that influence conclusions about causality, exposure–response relationships, susceptibility and cumulative risk, and by elucidating new biomarkers of exposure and effects. Additionally, NexGen has fostered extensive discussion among risk scientists and managers and improved confidence in interpreting and applying new data streams. Conclusions: While considerable uncertainties remain, thoughtful application of new knowledge to risk assessment appears reasonable for augmenting major scope assessments, forming the basis for or augmenting limited scope assessments, and for prioritization and screening of very data limited chemicals. Citation: Cote I

Risk assessment

International Nuclear Information System (INIS)

Kinchin, G.H.

1983-01-01

After defining risk and introducing the concept of individual and societal risk, the author considers each of these, restricting considerations to risk of death. Some probabilities of death arising from various causes are quoted, and attention drawn to the care necessary in making comparisons between sets of data and to the distinction between voluntary and involuntary categories and between early and delayed deaths. The presentation of information on societal risk is discussed and examples given. The history of quantified risk assessment is outlined, particularly related to the nuclear industry, the process of assessing risk discussed: identification of hazard causes, the development of accident chains and the use of event trees, the evaluation of probability through the collection of data and their use with fault trees, and the assessment of consequences of hazards in terms of fatalities. Reference is made to the human element and common-made failures, and to studies supporting the development of reliability assessment techniques. Acceptance criteria are discussed for individual and societal risk in the nuclear field, and it is shown that proposed criteria lead to risks conservative by comparison with risks from day-to-day accidents and other potentially hazardous industries. (U.K.)

Environmental risk assessment in GMO analysis.

Science.gov (United States)

Pirondini, Andrea; Marmiroli, Nelson

2010-01-01

Genetically modified or engineered organisms (GMOs, GEOs) are utilised in agriculture, expressing traits of interest, such as insect or herbicide resistance. Soybean, maize, cotton and oilseed rape are the GM crops with the largest acreage in the world. The distribution of GM acreage in the different countries is related with the different positions concerning labelling of GMO products: based on the principle of substantial equivalence, or rather based on the precautionary principle. The paper provides an overview on how the risks associated with release of GMO in the environments can be analysed and predicted, in view of a possible coexistence of GM and non-GM organisms in agriculture.Risk assessment procedures, both qualitative and quantitative, are compared in the context of application to GMOs considering also legislation requirements (Directive 2001/18/EC). Criteria and measurable properties to assess harm for human health and environmental safety are listed, and the possible consequences are evaluated in terms of significance.Finally, a mapping of the possible risks deriving from GMO release is reported, focusing on gene transfer to related species, horizontal gene transfer, direct and indirect effects on non target organisms, development of resistance in target organisms, and effects on biodiversity.

BIOLOGICAL RESPONSES OF THE SEA URCHIN, ARBACIA PUNTULATA, TO LEAD CONTAMINATION FOR AN ESTUARINE ECOLOGICAL RISK ASSESSMENT

Science.gov (United States)

An estuarine ecological risk assessment for the Portsmouth Naval Shipyard (PNS) Kittery, ME, was conducted utilizing the U.S. EPA's Framework for Ecological Risk Assessment (ERA). As part of the analysis phase of the ERA, laboratory studies were conducted to develop quantitative ...

Development of Improved Caprock Integrity and Risk Assessment Techniques

Energy Technology Data Exchange (ETDEWEB)

Bruno, Michael [Geomechanics Technologies, Incorporated, Monrovia, CA (United States)

2014-09-30

GeoMechanics Technologies has completed a geomechanical caprock integrity analysis and risk assessment study funded through the US Department of Energy. The project included: a detailed review of historical caprock integrity problems experienced in the natural gas storage industry; a theoretical description and documentation of caprock integrity issues; advanced coupled transport flow modelling and geomechanical simulation of three large-scale potential geologic sequestration sites to estimate geomechanical effects from CO₂ injection; development of a quantitative risk and decision analysis tool to assess caprock integrity risks; and, ultimately the development of recommendations and guidelines for caprock characterization and CO₂ injection operating practices. Historical data from gas storage operations and CO₂ sequestration projects suggest that leakage and containment incident risks are on the order of 10-1 to 10-2, which is higher risk than some previous studies have suggested for CO₂. Geomechanical analysis, as described herein, can be applied to quantify risks and to provide operating guidelines to reduce risks. The risk assessment tool developed for this project has been applied to five areas: The Wilmington Graben offshore Southern California, Kevin Dome in Montana, the Louden Field in Illinois, the Sleipner CO₂ sequestration operation in the North Sea, and the In Salah CO₂ sequestration operation in North Africa. Of these five, the Wilmington Graben area represents the highest relative risk while the Kevin Dome area represents the lowest relative risk.

Quantitative Deficits of Preschool Children at Risk for Mathematical Learning Disability

Directory of Open Access Journals (Sweden)

Felicia W. Chu

2013-05-01

Full Text Available The study tested the hypothesis that acuity of the potentially inherent approximate number system (ANS contributes to risk of mathematical learning disability (MLD. Sixty-eight (35 boys preschoolers at risk for school failure were assessed on a battery of quantitative tasks, and on intelligence, executive control, preliteracy skills, and parental education. Mathematics achievement scores at the end of one year of preschool indicated that 34 of these children were at high risk for MLD. Relative to the 34 typically achieving children, the at risk children were less accurate on the ANS task, and a one standard deviation deficit on this task resulted in a 2.4 fold increase in the odds of MLD status. The at risk children also had a poor understanding of ordinal relations, and had slower learning of Arabic numerals, number words, and their cardinal values. Poor performance on these tasks resulted in 3.6 to 4.5 fold increases in the odds of MLD status. The results provide some support for the ANS hypothesis but also suggest these deficits are not the primary source of poor mathematics learning.

Process Review for Development of Quantitative Risk Analyses for Transboundary Animal Disease to Pathogen-Free Territories

Directory of Open Access Journals (Sweden)

Jonathan Miller

2017-10-01

Full Text Available Outbreaks of transboundary animal diseases (TADs have the potential to cause significant detriment to animal, human, and environmental health; severe economic implications; and national security. Challenges concerning data sharing, model development, decision support, and disease emergence science have recently been promoted. These challenges and recommendations have been recognized and advocated in the disciplines intersecting with outbreak prediction and forecast modeling regarding infectious diseases. To advance the effective application of computation and risk communication, analytical products ought to follow a collaboratively agreed common plan for implementation. Research articles should seek to inform and assist prioritization of national and international strategies in developing established criteria to identify and follow best practice standards to assess risk model attributes and performance. A well-defined framework to help eliminate gaps in policy, process, and planning knowledge areas would help alleviate the intense need for the formation of a comprehensive strategy for countering TAD outbreak risks. A quantitative assessment that accurately captures the risk of introduction of a TAD through various pathways can be a powerful tool in guiding where government, academic, and industry resources ought to be allocated, whether implementation of additional risk management solutions is merited, and where research efforts should be directed to minimize risk. This review outlines a part of a process for the development of quantitative risk analysis to collect, analyze, and communicate this knowledge. A more comprehensive and unabridged manual was also developed. The framework used in supporting the application of aligning computational tools for readiness continues our approach to apply a preparedness mindset to challenges concerning threats to global biosecurity, secure food systems, and risk-mitigated agricultural economies.

Risk Assessment Overview

Science.gov (United States)

Prassinos, Peter G.; Lyver, John W., IV; Bui, Chinh T.

2011-01-01

Risk assessment is used in many industries to identify and manage risks. Initially developed for use on aeronautical and nuclear systems, risk assessment has been applied to transportation, chemical, computer, financial, and security systems among others. It is used to gain an understanding of the weaknesses or vulnerabilities in a system so modification can be made to increase operability, efficiency, and safety and to reduce failure and down-time. Risk assessment results are primary inputs to risk-informed decision making; where risk information including uncertainty is used along with other pertinent information to assist management in the decision-making process. Therefore, to be useful, a risk assessment must be directed at specific objectives. As the world embraces the globalization of trade and manufacturing, understanding the associated risk become important to decision making. Applying risk assessment techniques to a global system of development, manufacturing, and transportation can provide insight into how the system can fail, the likelihood of system failure and the consequences of system failure. The risk assessment can identify those elements that contribute most to risk and identify measures to prevent and mitigate failures, disruptions, and damaging outcomes. In addition, risk associated with public and environment impact can be identified. The risk insights gained can be applied to making decisions concerning suitable development and manufacturing locations, supply chains, and transportation strategies. While risk assessment has been mostly applied to mechanical and electrical systems, the concepts and techniques can be applied across other systems and activities. This paper provides a basic overview of the development of a risk assessment.

Quantitative microbial risk assessment for Escherichia coli O157:H7, salmonella, and Listeria monocytogenes in leafy green vegetables consumed at salad bars.

Science.gov (United States)

Franz, E; Tromp, S O; Rijgersberg, H; van der Fels-Klerx, H J

2010-02-01

Fresh vegetables are increasingly recognized as a source of foodborne outbreaks in many parts of the world. The purpose of this study was to conduct a quantitative microbial risk assessment for Escherichia coli O157:H7, Salmonella, and Listeria monocytogenes infection from consumption of leafy green vegetables in salad from salad bars in The Netherlands. Pathogen growth was modeled in Aladin (Agro Logistics Analysis and Design Instrument) using time-temperature profiles in the chilled supply chain and one particular restaurant with a salad bar. A second-order Monte Carlo risk assessment model was constructed (using @Risk) to estimate the public health effects. The temperature in the studied cold chain was well controlled below 5 degrees C. Growth of E. coli O157:H7 and Salmonella was minimal (17 and 15%, respectively). Growth of L. monocytogenes was considerably greater (194%). Based on first-order Monte Carlo simulations, the average number of cases per year in The Netherlands associated the consumption leafy greens in salads from salad bars was 166, 187, and 0.3 for E. coli O157:H7, Salmonella, and L. monocytogenes, respectively. The ranges of the average number of annual cases as estimated by second-order Monte Carlo simulation (with prevalence and number of visitors as uncertain variables) were 42 to 551 for E. coli O157:H7, 81 to 281 for Salmonella, and 0.1 to 0.9 for L. monocytogenes. This study included an integration of modeling pathogen growth in the supply chain of fresh leafy vegetables destined for restaurant salad bars using software designed to model and design logistics and modeling the public health effects using probabilistic risk assessment software.

Waste management project’s alternatives: A risk-based multi-criteria assessment (RBMCA) approach

International Nuclear Information System (INIS)

Karmperis, Athanasios C.; Sotirchos, Anastasios; Aravossis, Konstantinos; Tatsiopoulos, Ilias P.

2012-01-01

Highlights: ► We examine the evaluation of a waste management project’s alternatives. ► We present a novel risk-based multi-criteria assessment (RBMCA) approach. ► In the RBMCA the evaluation criteria are based on the quantitative risk analysis of the project’s alternatives. ► Correlation between the criteria weight values and the decision makers’ risk preferences is examined. ► Preference to the multi-criteria against the one-criterion evaluation process is discussed. - Abstract: This paper examines the evaluation of a waste management project’s alternatives through a quantitative risk analysis. Cost benefit analysis is a widely used method, in which the investments are mainly assessed through the calculation of their evaluation indicators, namely benefit/cost (B/C) ratios, as well as the quantification of their financial, technical, environmental and social risks. Herein, a novel approach in the form of risk-based multi-criteria assessment (RBMCA) is introduced, which can be used by decision makers, in order to select the optimum alternative of a waste management project. Specifically, decision makers use multiple criteria, which are based on the cumulative probability distribution functions of the alternatives’ B/C ratios. The RBMCA system is used for the evaluation of a waste incineration project’s alternatives, where the correlation between the criteria weight values and the decision makers’ risk preferences is analyzed and useful conclusions are discussed.

Use of epidemiologic data in Integrated Risk Information System (IRIS) assessments

International Nuclear Information System (INIS)

Persad, Amanda S.; Cooper, Glinda S.

2008-01-01

In human health risk assessment, information from epidemiologic studies is typically utilized in the hazard identification step of the risk assessment paradigm. However, in the assessment of many chemicals by the Integrated Risk Information System (IRIS), epidemiologic data, both observational and experimental, have also been used in the derivation of toxicological risk estimates (i.e., reference doses [RfD], reference concentrations [RfC], oral cancer slope factors [CSF] and inhalation unit risks [IUR]). Of the 545 health assessments posted on the IRIS database as of June 2007, 44 assessments derived non-cancer or cancer risk estimates based on human data. RfD and RfC calculations were based on a spectrum of endpoints from changes in enzyme activity to specific neurological or dermal effects. There are 12 assessments with IURs based on human data, two assessments that extrapolated human inhalation data to derive CSFs and one that used human data to directly derive a CSF. Lung or respiratory cancer is the most common endpoint for cancer assessments based on human data. To date, only one chemical, benzene, has utilized human data for derivation of all three quantitative risk estimates (i.e., RfC, RfD, and dose-response modeling for cancer assessment). Through examples from the IRIS database, this paper will demonstrate how epidemiologic data have been used in IRIS assessments for both adding to the body of evidence in the hazard identification process and in the quantification of risk estimates in the dose-response component of the risk assessment paradigm

Qualitative risk assessment: a conceptual context and three diverse applications

International Nuclear Information System (INIS)

Elsea, K.J.; Conger, D.S.

1992-01-01

Risk is defined as the probability of an occurrence multiplied by the consequences of that occurrence. Such a definition implies a quantitative or at least a mathematical operation. However, qualitative uses of risk have proved useful tools in incident investigation and management decision making. This paper provides a conceptual context for qualitative risk assessment and discusses three efforts at subject organizations [an aerospace firm, a US Department of Energy weapons-related facility, and a commercial nuclear reactor] that have applied qualitative risk techniques for different uses and with different results. A lessons-learned section summarizes and provides future direction

Introduction to risk assessment

International Nuclear Information System (INIS)

Raina, V.M.

2002-01-01

This paper gives an introduction to risk assessment. It discusses the basic concepts of risk assessment, nuclear risk assessment process and products, the role of risk assessment products in nuclear safety assurance, the relationship between risk assessment and other safety analysis and risk assessment and safe operating envelope

Significant vestibular system impairment is common in a cohort of elderly patients referred for assessment of falls risk.

Science.gov (United States)

Jacobson, Gary P; McCaslin, Devin L; Grantham, Sarah L; Piker, Erin G

2008-01-01

Falls in elderly patients are associated with morbidity, mortality, and cost to the healthcare system. The development of falls risk assessment programs have represented a method of responding to what is known about injurious falls. The multidimensional assessments involve the comparison against normative data of a patient's performance on metrics known to influence the likelihood of future falls. The factors assessed usually include falls and medication history, measures of mentation, depression, orthostatic hypotension, simple or choice reaction time, gait stability, postural stability, and the integrity of the patient's vision, somesthetic, and vestibular senses. This investigation was conducted to measure the proportion of patients referred for falls risk assessment who have evidence of vestibular system impairment. Qualitative, retrospective review of data collected from 2003 to 2007. The cohort was 185 consecutive patients referred for multidimensional assessments of falls risk. Patients underwent quantitative assessments of peripheral and central vestibular system function consisting of electro- or videonystagmography (i.e., ENG/VNG), and sinusoidal harmonic acceleration testing. Results of these tests were compared to normative data. We found that 73% of the sample who underwent vestibular system assessment had quantitative evidence of either peripheral or central vestibular system impairment. Our results suggest that quantitative assessments of the vestibulo-ocular reflex should be conducted on patients who are evaluated for falls risk. These examinations should include at least caloric testing and, where available, rotational testing.

From risk analysis to risk control in land transport of dangerous materials. Contribution of quantitative evaluation

International Nuclear Information System (INIS)

Hubert, Ph.; Pages, P.

1985-03-01

The different approaches of risks and risk management system are described: statistics, potential risk, prevention, information and intervention. Quantitative evaluation is developed: data collection, purposes and methods. Two examples of application are given on risks associated to road transport of propane and of uranium hexafluoride. In conclusion level of risk and practical use of studies on risks are examined. 41 refs [fr

Cumulative Risk Assessment (CRA): transforming the way we assess health risks.

Science.gov (United States)

Williams, Pamela R D; Dotson, G Scott; Maier, Andrew

2012-10-16

Human health risk assessments continue to evolve and now focus on the need for cumulative risk assessment (CRA). CRA involves assessing the combined risk from coexposure to multiple chemical and nonchemical stressors for varying health effects. CRAs are broader in scope than traditional chemical risk assessments because they allow for a more comprehensive evaluation of the interaction between different stressors and their combined impact on human health. Future directions of CRA include greater emphasis on local-level community-based assessments; integrating environmental, occupational, community, and individual risk factors; and identifying and implementing common frameworks and risk metrics for incorporating multiple stressors.

Fuzzy hierarchical model for risk assessment principles, concepts, and practical applications

CERN Document Server

Chan, Hing Kai

2013-01-01

Risk management is often complicated by situational uncertainties and the subjective preferences of decision makers. Fuzzy Hierarchical Model for Risk Assessment introduces a fuzzy-based hierarchical approach to solve risk management problems considering both qualitative and quantitative criteria to tackle imprecise information.   This approach is illustrated through number of case studies using examples from the food, fashion and electronics sectors to cover a range of applications including supply chain management, green product design and green initiatives. These practical examples explore how this method can be adapted and fine tuned to fit other industries as well.   Supported by an extensive literature review, Fuzzy Hierarchical Model for Risk Assessment  comprehensively introduces a new method for project managers across all industries as well as researchers in risk management.

urrent status and assessment of quantitative and qualitative one leg ...

African Journals Online (AJOL)

... of only a quantitative assessment. These findings indicate that, when evaluating the one leg balance in children aged 3-6 years, a quantitative and qualitative assessment should be used in combination together to assure a more accurate assessment. (S. African J. for Research in Sport, Physical Ed. and Recreation: 2001 ...

Clinical risk assessment in intensive care unit

Directory of Open Access Journals (Sweden)

Saeed Asefzadeh

2013-01-01

Full Text Available Background: Clinical risk management focuses on improving the quality and safety of health care services by identifying the circumstances and opportunities that put patients at risk of harm and acting to prevent or control those risks. The goal of this study is to identify and assess the failure modes in the ICU of Qazvin′s Social Security Hospital (Razi Hospital through Failure Mode and Effect Analysis (FMEA. Methods: This was a qualitative-quantitative research by Focus Discussion Group (FDG performed in Qazvin Province, Iran during 2011. The study population included all individuals and owners who are familiar with the process in ICU. Sampling method was purposeful and the FDG group members were selected by the researcher. The research instrument was standard worksheet that has been used by several researchers. Data was analyzed by FMEA technique. Results: Forty eight clinical errors and failure modes identified, results showed that the highest risk probability number (RPN was in respiratory care "Ventilator′s alarm malfunction (no alarm" with the score 288, and the lowest was in gastrointestinal "not washing the NG-Tube" with the score 8. Conclusions: Many of the identified errors can be prevented by group members. Clinical risk assessment and management is the key to delivery of effective health care.

The importance of radiation risk assessment

International Nuclear Information System (INIS)

Pochin, E.E.

1979-01-01

In its Publication 26, ICRP recommends a system of radiation dose limitation that is designed to ensure adequate protection from the harmful effects of radiation in conditions both of occupational and of environmental exposure. Clearly, however, no such system can be recommended or accepted as sufficiently safe unless the risks of the resultant exposures have been quantitatively assessed. Publication 26 reflects the increasing quantitative information that is now available on (a) carcinogenic risks of radiation in man, both from exposure of the whole body and from that of individual organs, at moderate exposures; (b) theoretical bases for inference of risk, from moderate to lower exposures; (c) genetic risks in the mouse, and inferences from such risks to those in man; (d) the dose equivalent levels at which certain non-stochastic effects may be induced. Despite a number of uncertainties, substantially improved estimates can therefore be made of the levels of safety that are likely to be achieved by observing the Commission's recommended dose limits, and the associated system of limitation of exposures to levels as low as reasonably achievable below these limits. Both for occupational exposure and for the exposure of the members of the public, these estimates are expressed in Publication 26 in terms of the risk of inducing fatal malignancies or serious hereditary ill health. These frequencies are compared with those of occupational fatalities in other industries or with accidental fatalities amongst the general public. The comparison between harm from radiation and from other agents in different industries is extended in ICRP-27 (on ''Problems Involved in Developing an Index of Harm'') in a review of the time lost through occupational diseases and non-fatal accidents, as well as from fatal diseases and accidents, so that the levels of safety achievable by the Commission's recommendations can be reviewed in the general perspective of occupational safety. (author)

Chemical Exposure Assessment Program at Los Alamos National Laboratory: A risk based approach

International Nuclear Information System (INIS)

Stephenson, D.J.

1996-01-01

The University of California Contract And DOE Order 5480.10 require that Los Alamos National Laboratory (LANL) perform health hazard assessments/inventories of all employee workplaces. In response to this LANL has developed the Chemical Exposure Assessment Program. This program provides a systematic risk-based approach to anticipation, recognition, evaluation and control of chemical workplace exposures. Program implementation focuses resources on exposures with the highest risks for causing adverse health effects. Implementation guidance includes procedures for basic characterization, qualitative risk assessment, quantitative validation, and recommendations and reevaluation. Each component of the program is described. It is shown how a systematic method of assessment improves documentation, retrieval, and use of generated exposure information

Biomechanical rupture risk assessment of abdominal aortic aneurysms based on a novel probabilistic rupture risk index.

Science.gov (United States)

Polzer, Stanislav; Gasser, T Christian

2015-12-06

A rupture risk assessment is critical to the clinical treatment of abdominal aortic aneurysm (AAA) patients. The biomechanical AAA rupture risk assessment quantitatively integrates many known AAA rupture risk factors but the variability of risk predictions due to model input uncertainties remains a challenging limitation. This study derives a probabilistic rupture risk index (PRRI). Specifically, the uncertainties in AAA wall thickness and wall strength were considered, and wall stress was predicted with a state-of-the-art deterministic biomechanical model. The discriminative power of PRRI was tested in a diameter-matched cohort of ruptured (n = 7) and intact (n = 7) AAAs and compared to alternative risk assessment methods. Computed PRRI at 1.5 mean arterial pressure was significantly (p = 0.041) higher in ruptured AAAs (20.21(s.d. 14.15%)) than in intact AAAs (3.71(s.d. 5.77)%). PRRI showed a high sensitivity and specificity (discriminative power of 0.837) to discriminate between ruptured and intact AAA cases. The underlying statistical representation of stochastic data of wall thickness, wall strength and peak wall stress had only negligible effects on PRRI computations. Uncertainties in AAA wall stress predictions, the wide range of reported wall strength and the stochastic nature of failure motivate a probabilistic rupture risk assessment. Advanced AAA biomechanical modelling paired with a probabilistic rupture index definition as known from engineering risk assessment seems to be superior to a purely deterministic approach. © 2015 The Author(s).

Assessment of Logistics Risk using Collective Artificial Intelligence

Directory of Open Access Journals (Sweden)

Skitsko Volodymyr I.

2017-12-01

Full Text Available In substantiating management decisions in logistics, there can be used various economic and mathematical methods and models for quantitative risk assessment constructed with the help of a variety of instruments. Due to the increase in the processing power of computer equipment, economic and mathematical models become more complex, more precise, and the range of modeling tools expands. The current promising area in mathematical modeling is collective artificial intelligence, with the help of which it is possible to effectively solve weakly structured, multi-criteria, multi-purpose, complex economic problems. The mathematical model of the bat algorithm, the basic rules and steps of its functioning are presented, the application of the bat algorithm to solve the multi-index transport problem in the formulation of which the logistics risk is taken into account is shown, and the way to assess the logistics risk using the results of the functioning of the bat algorithm is shown.

Validation study of a quantitative multigene reverse transcriptase-polymerase chain reaction assay for assessment of recurrence risk in patients with stage II colon cancer.

Science.gov (United States)

Gray, Richard G; Quirke, Philip; Handley, Kelly; Lopatin, Margarita; Magill, Laura; Baehner, Frederick L; Beaumont, Claire; Clark-Langone, Kim M; Yoshizawa, Carl N; Lee, Mark; Watson, Drew; Shak, Steven; Kerr, David J

2011-12-10

We developed quantitative gene expression assays to assess recurrence risk and benefits from chemotherapy in patients with stage II colon cancer. We sought validation by using RNA extracted from fixed paraffin-embedded primary colon tumor blocks from 1,436 patients with stage II colon cancer in the QUASAR (Quick and Simple and Reliable) study of adjuvant fluoropyrimidine chemotherapy versus surgery alone. A recurrence score (RS) and a treatment score (TS) were calculated from gene expression levels of 13 cancer-related genes (n = 7 recurrence genes and n = 6 treatment benefit genes) and from five reference genes with prespecified algorithms. Cox proportional hazards regression models and log-rank methods were used to analyze the relationship between the RS and risk of recurrence in patients treated with surgery alone and between TS and benefits of chemotherapy. Risk of recurrence was significantly associated with RS (hazard ratio [HR] per interquartile range, 1.38; 95% CI, 1.11 to 1.74; P = .004). Recurrence risks at 3 years were 12%, 18%, and 22% for predefined low, intermediate, and high recurrence risk groups, respectively. T stage (HR, 1.94; P < .001) and mismatch repair (MMR) status (HR, 0.31; P < .001) were the strongest histopathologic prognostic factors. The continuous RS was associated with risk of recurrence (P = .006) beyond these and other covariates. There was no trend for increased benefit from chemotherapy at higher TS (P = .95). The continuous 12-gene RS has been validated in a prospective study for assessment of recurrence risk in patients with stage II colon cancer after surgery and provides prognostic value that complements T stage and MMR. The TS was not predictive of chemotherapy benefit.

A quantitative screening-level approach to incorporate chemical exposure and risk into alternative assessment evaluations.

Science.gov (United States)

Arnold, Scott M; Greggs, Bill; Goyak, Katy O; Landenberger, Bryce D; Mason, Ann M; Howard, Brett; Zaleski, Rosemary T

2017-11-01

As the general public and retailers ask for disclosure of chemical ingredients in the marketplace, a number of hazard screening tools were developed to evaluate the so-called "greenness" of individual chemical ingredients and/or formulations. The majority of these tools focus only on hazard, often using chemical lists, ignoring the other part of the risk equation: exposure. Using a hazard-only focus can result in regrettable substitutions, changing 1 chemical ingredient for another that turns out to be more hazardous or shifts the toxicity burden to others. To minimize the incidents of regrettable substitutions, BizNGO describes "Common Principles" to frame a process for informed substitution. Two of these 6 principles are: "reduce hazard" and "minimize exposure." A number of frameworks have emerged to evaluate and assess alternatives. One framework developed by leading experts under the auspices of the US National Academy of Sciences recommended that hazard and exposure be specifically addressed in the same step when assessing candidate alternatives. For the alternative assessment community, this article serves as an informational resource for considering exposure in an alternatives assessment using elements of problem formulation; product identity, use, and composition; hazard analysis; exposure analysis; and risk characterization. These conceptual elements build on practices from government, academia, and industry and are exemplified through 2 hypothetical case studies demonstrating the questions asked and decisions faced in new product development. These 2 case studies-inhalation exposure to a generic paint product and environmental exposure to a shampoo rinsed down the drain-demonstrate the criteria, considerations, and methods required to combine exposure models addressing human health and environmental impacts to provide a screening level hazard and exposure (risk) analysis. This article informs practices for these elements within a comparative risk context

Risk assessment of work at height in construction

Directory of Open Access Journals (Sweden)

Letice Dalla Lana

2014-02-01

Full Text Available The construction presents alarming statistics when it comes to the risks that these workers are subject. Higher risks still present work at a height where the fall is the biggest causal factor of fatal accidents. Thus the managements of companies who seek to reduce these risks and this has going for technical evaluation of operational risks. Three of these techniques are discussed in this article: PHA, FTA and CIT. The goal is to determine which one is most effective in assessing the risks of working at height in construction. The methodology used was case study of three works on three different construction of Santa Maria, RS. For a better understanding of the phenomenon suggests that the techniques are used together, but the CIT has provided a better quantitative analysis of incidents and the PHA contributes towards already establish the possible effects that each risk may have.

Quantitative microbial risk assessment (QMRA) shows increased public health risk associated with exposure to river water under conditions of riverbed sediment resuspension.

Science.gov (United States)

Abia, Akebe Luther King; Ubomba-Jaswa, Eunice; Genthe, Bettina; Momba, Maggy Ndombo Benteke

2016-10-01

Although higher microbial concentrations have been reported in sediments than in the overlying water column, most quantitative microbial risk assessment (QMRA) studies have not clearly indicated the contribution of sediment-borne pathogens to estimated risks. Thus, the present study aimed at determining the public health risk associated with exposure to pathogenic bacteria in polluted river water under undisturbed conditions and conditions of sediment resuspension in the Apies River, Gauteng, South Africa. Microbial pathogens were isolated and identified using culture and molecular methods. The beta-Poisson dose-response model was used to estimate the probability of infection (Pi) with the various pathogens, following accidental/intentional ingestion of 1mL or 100mL (or 50mL) of untreated river water. Mean wet season Escherichia coli counts ranged between 5.8E+01 and 8.8E+04MPN/100mL (water column) and between 2.40E+03 and 1.28E+05MPN/100mL (sediments). Mean dry season E. coli counts ranged between 5.11E+00 and 3.40E+03MPN/100mL (water column) and between 5.09E+00 and 6.30E+03MPN/100mL (sediments). Overall (water and sediments) Vibrio cholerae was the most detected pathogen (58.8%) followed by Salmonella spp. (23.9%) and Shigella (10.1%). Ingestion of 1mL of river water could lead to 0%-4% and 1%-74% Pi with E. coli during the dry and wet season, respectively. During the dry season, the Pi with V. cholerae, Salmonella spp. and Shigella spp. were 0%-1.39%, 0%-4.11% and 0%-0.16% respectively, depending on volume of water ingested. The risks of infections with all microorganisms increased during the wet season. A 2-log increase in water E. coli count following sediments disturbance led to approximately 10 times higher Pi with E. coli than when sediments were undisturbed. Therefore, the use of the untreated water from the Apies River for drinking, household purposes or recreational activities poses a potential health risk to the users of the river. Copyright © 2016

Fire risk assessment in Germany. Procedure, data, results

International Nuclear Information System (INIS)

Berg, H.P.

2000-01-01

The recommended approach for a quantitative fire risk assessment to be applied within periodic safety reviews of nuclear power plants in Germany starts with a screening process providing critical fire zones and is followed by a quantitative analysis using a standard event tree with elements for fire initiation, ventilation of the room, fire detection, fire suppression, and fire propagation. In a final step, the fire induced frequency of initiating events, the main contributors and the calculated hazard state frequency for the fire event are determined. For that purpose, a comprehensive data base is needed which has been developed in particular for active fire protection measures. As an example results of one fire PSA are reported. (author)

Computer-Aided Nodule Assessment and Risk Yield Risk Management of Adenocarcinoma: The Future of Imaging?

Science.gov (United States)

Foley, Finbar; Rajagopalan, Srinivasan; Raghunath, Sushravya M; Boland, Jennifer M; Karwoski, Ronald A; Maldonado, Fabien; Bartholmai, Brian J; Peikert, Tobias

2016-01-01

Increased clinical use of chest high-resolution computed tomography results in increased identification of lung adenocarcinomas and persistent subsolid opacities. However, these lesions range from very indolent to extremely aggressive tumors. Clinically relevant diagnostic tools to noninvasively risk stratify and guide individualized management of these lesions are lacking. Research efforts investigating semiquantitative measures to decrease interrater and intrarater variability are emerging, and in some cases steps have been taken to automate this process. However, many such methods currently are still suboptimal, require validation and are not yet clinically applicable. The computer-aided nodule assessment and risk yield software application represents a validated tool for the automated, quantitative, and noninvasive tool for risk stratification of adenocarcinoma lung nodules. Computer-aided nodule assessment and risk yield correlates well with consensus histology and postsurgical patient outcomes, and therefore may help to guide individualized patient management, for example, in identification of nodules amenable to radiological surveillance, or in need of adjunctive therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

Waste area Grouping 2 Phase I task data report: Human health risk assessment

International Nuclear Information System (INIS)

Purucker, S.T.; Douthat, D.M.

1996-06-01

This report is one of five reports issued in 1996 that provide follow- up information to the Phase 1 Remedial Investigation (RI) Report for Waste Area Grouping (WAG) 2 at Oak Ridge National Laboratory (ORNL). The five reports address areas of concern that could cause potential human health risk and ecological risk within WAG2 at ORNL. The purpose of this report is to present a summary of the human health risk assessment results based on the data collected for the WAG 2 Phase 1 RI. Estimates of risk are provided based on measured concentrations in the surface water, floodplain soil, and sediment of White Oak Creek, Melton Branch, and their tributaries. The human health risk assessment methodology used in this risk assessment is based on Risk Assessment Guidance for Superfund (RAGS). First, the data for the different media are elevated to determine usability for risk assessment. Second, through the process of selecting chemicals of potential concern (COPCs), contaminants to be considered in the risk assessment are identified for each assessment of exposure potential is performed, and exposure pathways are identified. Subsequently, exposure is estimated quantitatively, and the toxicity of each of the COPCs is determined. The results of these analyses are combined and summarized in a risk characterization

Risk assessment as rhetorical practice: The ironic mathematics behind terrorism, banking, and public policy.

Science.gov (United States)

Danisch, Robert

2013-02-01

The twin problems of possible terrorist attacks and a global economic recession have been, and continue to be, critical components of contemporary political culture. At the center of both problems is the assessment of future risk. To calculate the probability that a loan will default or to estimate the likelihood of an act of bioterrorism crippling an American city is to engage in the quantitative science of risk assessment. The process of risk assessment is an attempt to rationalize the uncertainty and contingency of the future. In this essay, I read risk assessments made by the Department of Homeland Security and by major banks during the recent financial collapse as examples of rhetorical practice. As such, I show the rhetorical form and function of risk assessments in order to determine the effect that they have on contemporary political culture.

Variability and uncertainty in Swedish exposure factors for use in quantitative exposure assessments.

Science.gov (United States)

Filipsson, Monika; Öberg, Tomas; Bergbäck, Bo

2011-01-01

Information of exposure factors used in quantitative risk assessments has previously been compiled and reported for U.S. and European populations. However, due to the advancement of science and knowledge, these reports are in continuous need of updating with new data. Equally important is the change over time of many exposure factors related to both physiological characteristics and human behavior. Body weight, skin surface, time use, and dietary habits are some of the most obvious examples covered here. A wealth of data is available from literature not primarily gathered for the purpose of risk assessment. Here we review a number of key exposure factors and compare these factors between northern Europe--here represented by Sweden--and the United States. Many previous compilations of exposure factor data focus on interindividual variability and variability between sexes and age groups, while uncertainty is mainly dealt with in a qualitative way. In this article variability is assessed along with uncertainty. As estimates of central tendency and interindividual variability, mean, standard deviation, skewness, kurtosis, and multiple percentiles were calculated, while uncertainty was characterized using 95% confidence intervals for these parameters. The presented statistics are appropriate for use in deterministic analyses using point estimates for each input parameter as well as in probabilistic assessments. © 2010 Society for Risk Analysis.

An OECD perspective of the role of risk assessment in policy development

Energy Technology Data Exchange (ETDEWEB)

Brydon, Jim [Environmental Health and Safety Division, Organization for Economic Co-operation and Development, Paris (France)

1992-07-01

OECD is an intergovernmental organization bringing together 24 industrialised countries from North America, Western Europe, and the Pacific. Its basic aims include the following: - to achieve high sustainable development, economic growth and employment; - to achieve high economic and social welfare and a high standard of living throughout the OECD area and in non-Member countries: The specialised Agencies and Directorates of OECD cover the full breadth of economic and social activities of concern to the Conference. Under their programmes, there are a variety of activities which involve various elements of qualitative and quantitative risk assessment. Risk assessment methodology, policies options regarding the use of risk assessment, the role of risk assessment in policy and decision-making are all routine in OECD work. This work ranges from, for example, work on the economics of investment policies, through work on food safety, to the analysis of nuclear safety technology.

An OECD perspective of the role of risk assessment in policy development

International Nuclear Information System (INIS)

Brydon, Jim

1992-01-01

OECD is an intergovernmental organization bringing together 24 industrialised countries from North America, Western Europe, and the Pacific. Its basic aims include the following: - to achieve high sustainable development, economic growth and employment; - to achieve high economic and social welfare and a high standard of living throughout the OECD area and in non-Member countries: The specialised Agencies and Directorates of OECD cover the full breadth of economic and social activities of concern to the Conference. Under their programmes, there are a variety of activities which involve various elements of qualitative and quantitative risk assessment. Risk assessment methodology, policies options regarding the use of risk assessment, the role of risk assessment in policy and decision-making are all routine in OECD work. This work ranges from, for example, work on the economics of investment policies, through work on food safety, to the analysis of nuclear safety technology

Risk analysis within environmental impact assessment of proposed construction activity

Energy Technology Data Exchange (ETDEWEB)

Zeleňáková, Martina; Zvijáková, Lenka

2017-01-15

Environmental impact assessment is an important process, prior to approval of the investment plan, providing a detailed examination of the likely and foreseeable impacts of proposed construction activity on the environment. The objective of this paper is to develop a specific methodology for the analysis and evaluation of environmental impacts of selected constructions – flood protection structures using risk analysis methods. The application of methodology designed for the process of environmental impact assessment will develop assumptions for further improvements or more effective implementation and performance of this process. The main objective of the paper is to improve the implementation of the environmental impact assessment process. Through the use of risk analysis methods in environmental impact assessment process, the set objective has been achieved. - Highlights: This paper is informed by an effort to develop research with the aim of: • Improving existing qualitative and quantitative methods for assessing the impacts • A better understanding of relations between probabilities and consequences • Methodology for the EIA of flood protection constructions based on risk analysis • Creative approaches in the search for environmentally friendly proposed activities.

Risk analysis within environmental impact assessment of proposed construction activity

International Nuclear Information System (INIS)

Zeleňáková, Martina; Zvijáková, Lenka

2017-01-01

Environmental impact assessment is an important process, prior to approval of the investment plan, providing a detailed examination of the likely and foreseeable impacts of proposed construction activity on the environment. The objective of this paper is to develop a specific methodology for the analysis and evaluation of environmental impacts of selected constructions – flood protection structures using risk analysis methods. The application of methodology designed for the process of environmental impact assessment will develop assumptions for further improvements or more effective implementation and performance of this process. The main objective of the paper is to improve the implementation of the environmental impact assessment process. Through the use of risk analysis methods in environmental impact assessment process, the set objective has been achieved. - Highlights: This paper is informed by an effort to develop research with the aim of: • Improving existing qualitative and quantitative methods for assessing the impacts • A better understanding of relations between probabilities and consequences • Methodology for the EIA of flood protection constructions based on risk analysis • Creative approaches in the search for environmentally friendly proposed activities.

Quantitative evaluation of risks for individuals in diagnostic radiology

Energy Technology Data Exchange (ETDEWEB)

Iinuma, T A; Tateno, Y; Hashizume, T [National Inst. of Radiological Sciences, Chiba (Japan)

1980-05-01

A method to estimate quantitatively risks of individual patients due to exposure to diagnostic radiation (carcinogenetic and genetic effects of radiation) was proposed on the basis of ICRP-26. Carcinogenetic effect of radiation was calculated by multiplying mean dose equivalent for each organ per each radiological examination by shortening of average life-expectancy which was calculated from incidence of fetal carcinoma of each organ, latent period of carcinoma, and incidence period of carcinoma. Genetic effect of radiation was calculated by multiplying mean dose equivalent for gonad per each radiological examination by incidence of genetically severe radiation damages due to parent's exposure and child expectancy rate. Three examples were shown on calculations of risks in the photofluorographic examinations of the stomach and chest, and mammography. The same method of calculation could be applied to the in-vivo nuclear medicine examinations. Further investigation was required to calculate the risks quantitatively for various types of diagnostic procedures using radiation.

Quantitative evaluation of risks for individuals in diagnostic radiology

International Nuclear Information System (INIS)

Iinuma, T.A.; Tateno, Yukio; Hashizume, Tadashi

1980-01-01

A method to estimate quantitatively risks of individual patients due to exposure to diagnostic radiation (carcinogenetic and genetic effects of radiation) was proposed on the basis of ICRP-26. Carcinogenetic effect of radiation was calculated by multiplying mean dose equivalent for each organ per each radiological examination by shortening of average life-expectancy which was calculated from incidence of fetal carcinoma of each organ, latent period of carcinoma, and incidence period of carcinoma. Genetic effect of radiation was calculated by multiplying mean dose equivalent for gonad per each radiological examination by incidence of genetically severe radiation damages due to parent's exposure and child expectancy rate. Three examples were shown on calculations of risks in the photofluorographic examinations of the stomach and chest, and mammography. The same method of calculation could be applied to the in-vivo nuclear medicine examinations. Further investigation was required to calculate the risks quantitatively for various types of diagnostic procedures using radiation. (Tsunoda, M.)

Operational risk assessment.

Science.gov (United States)

McKim, Vicky L

2017-06-01

In the world of risk management, which encompasses the business continuity disciplines, many types of risk require evaluation. Financial risk is most often the primary focus, followed by product and market risks. Another critical area, which typically lacks a thorough review or may be overlooked, is operational risk. This category encompasses many risk exposure types including those around building structures and systems, environmental issues, nature, neighbours, clients, regulatory compliance, network, data security and so on. At times, insurance carriers will assess internal hazards, but seldom do these assessments include more than a cursory look at other types of operational risk. In heavily regulated environments, risk assessments are required but may not always include thorough assessments of operational exposures. Vulnerabilities may linger or go unnoticed, only to become the catalyst for a business disruption at a later time, some of which are so severe that business recovery becomes nearly impossible. Businesses may suffer loss of clients as the result of a prolonged disruption of services. Comprehensive operational risk assessments can assist in identifying such vulnerabilities, exposures and threats so that the risk can be minimised or removed. This paper lays out how an assessment of this type can be successfully conducted.

Multi-hazard national-level risk assessment in Africa using global approaches

Science.gov (United States)

Fraser, Stuart; Jongman, Brenden; Simpson, Alanna; Murnane, Richard

2016-04-01

In recent years Sub-Saharan Africa has been characterized by unprecedented opportunity for transformation and sustained growth. However, natural disasters such as droughts, floods, cyclones, earthquakes, landslides, volcanic eruptions and extreme temperatures cause significant economic and human losses, and major development challenges. Quantitative disaster risk assessments are an important basis for governments to understand disaster risk in their country, and to develop effective risk management and risk financing solutions. However, the data-scarce nature of many Sub-Saharan African countries as well as a lack of financing for risk assessments has long prevented detailed analytics. Recent advances in globally applicable disaster risk modelling practices and data availability offer new opportunities. In December 2013 the European Union approved a € 60 million contribution to support the development of an analytical basis for risk financing and to accelerate the effective implementation of a comprehensive disaster risk reduction. The World Bank's Global Facility for Disaster Reduction and Recovery (GFDRR) was selected as the implementing partner of the Program for Result Area 5: the "Africa Disaster Risk Assessment and Financing Program." As part of this effort, the GFDRR is overseeing the production of national-level multi-hazard risk profiles for a range of countries in Sub-Saharan Africa, using a combination of national and global datasets and state-of-the-art hazard and risk assessment methodologies. In this presentation, we will highlight the analytical approach behind these assessments, and show results for the first five countries for which the assessment has been completed (Kenya, Uganda, Senegal, Niger and Ethiopia). The presentation will also demonstrate the visualization of the risk assessments into understandable and visually attractive risk profile documents.

HOW TO CALCULATE INFORMATION VALUE FOR EFFECTIVE SECURITY RISK ASSESSMENT

Directory of Open Access Journals (Sweden)

Mario Sajko

2006-12-01

Full Text Available The actual problem of information security (infosec risk assessment is determining the value of information property or asset. This is particularly manifested through the use of quantitative methodology in which it is necessary to state the information value in quantitative sizes. The aim of this paper is to describe the evaluation possibilities of business information values, and the criteria needed for determining importance of information. For this purpose, the dimensions of information values will be determined and the ways used to present the importance of information contents will be studied. There are two basic approaches that can be used in evaluation: qualitative and quantitative. Often they are combined to determine forms of information content. The proposed criterion is the three-dimension model, which combines the existing experiences (i.e. possible solutions for information value assessment with our own criteria. An attempt for structuring information value in a business environment will be made as well.

Probabilistic earthquake risk assessment as a tool to improve safety and explanatory adequacy

International Nuclear Information System (INIS)

Itoi, Tatsuya

2015-01-01

This paper explains the concept of probabilistic earthquake risk assessment, mainly from the viewpoint as a tool to improve safety and explanatory adequacy. The definition of risk is the expected value of undesirable effect in an engineering meaning that is likely to occur in the future, and it is defined in risk management as the triplet of scenario (what can happen), frequency, and impact. As for the earthquake risk assessment of a nuclear power plant, the fragility of structure / system / component (SSC) against earthquake (so-called earthquake fragility) is assessed, and by combining with the earthquake hazard that has been separately obtained, the occurrence frequency and impact of the accident are obtained. From the view of the authors, earthquake risk assessment is for the purpose of decision-making, and is not intended to calculate the probability in a scientifically rigorous manner. For ensuring the quality of risk assessment, the table of 'Expert utilization standards for the evaluation of epistemological uncertainty' is used. Sole quantitative risk assessment is not necessarily sufficient for risk management. It would be important to find how to build the 'framework for comprehensive decision-making.' (A.O.)

Novel Threat-risk Index Using Probabilistic Risk Assessment and Human Reliability Analysis - Final Report

Energy Technology Data Exchange (ETDEWEB)

George A. Beitel

2004-02-01

In support of a national need to improve the current state-of-the-art in alerting decision makers to the risk of terrorist attack, a quantitative approach employing scientific and engineering concepts to develop a threat-risk index was undertaken at the Idaho National Engineering and Environmental Laboratory (INEEL). As a result of this effort, a set of models has been successfully integrated into a single comprehensive model known as Quantitative Threat-Risk Index Model (QTRIM), with the capability of computing a quantitative threat-risk index on a system level, as well as for the major components of the system. Such a threat-risk index could provide a quantitative variant or basis for either prioritizing security upgrades or updating the current qualitative national color-coded terrorist threat alert.

Quantitative microbial risk assessment of Salmonella in dry fermented sausage (salami) in Southern Brazil

DEFF Research Database (Denmark)

Corbellini, Luis Gustavo; Costa, Eduardo de Freitas; Cardoso, Marisa

2017-01-01

Dry fermented sausage (salami) is a very popular ready-to-eat product in Southern Brazil, of which the raw materials can be contaminated with pathogens such as Salmonella. This product can put consumers at risk if a failure occurs during the manufacturing process. To investigate this risk...... and heterogeneous). In general, it was observed that the mean exposure to Salmonella due to ingestion of a portion of contaminated salami was very low; "zero risks" (with no cases of salmonellosis among 100,000 consumed portions of salami) were found in 65% of the scenarios (265/405) assessed and low risks were...... low, selling dry fermented sausage before complete maturation of the product and failure in fermentation can pose a risk to the consumers from the studied region. It was found that a maturation period of 24 days can be considered safe, even in a situation with high initial levels of contamination....

A spatially-evaluated methodology for assessing risk to a population from contaminated land

International Nuclear Information System (INIS)

Gay, J. Rebecca; Korre, Anna

2006-01-01

A methodology is proposed which combines quantitative probabilistic human health risk assessment and spatial statistical methods (geostatistics) to produce an assessment of risks to human health from exposure to contaminated land, in a manner which preserves the spatial distribution of risks and provides a measure of uncertainty in the assessment. Maps of soil contaminant levels, which incorporate uncertainty, are produced from sparse sample data using sequential indicator simulation. A real, age-stratified population is mapped across the contaminated area, and intake of soil contaminants by individuals is calculated probabilistically using an adaptation of the Contaminated Land Exposure Assessment (CLEA) model. An abundance of information is contained in results which can be interrogated at the population and individual level, and mapped to provide a powerful visual tool for risk managers, enabling efficient targeting of risk reduction measures to different locations. - A methodology for calculating and mapping risks to a population from intake of soil contaminants

Formulation and Presentation of Risk Assessments to Address Risk Targets for Radioactive Waste Disposal

International Nuclear Information System (INIS)

Wilmot, R.D.

2002-10-01

. Supporting calculations to explore these issues quantitatively could provide additional support for conducting such a review. Regulatory guidance on these issues would be a further means of supporting the review process. In addition to a review of approaches to the calculation of risk, the report also examines alternative measures that have been proposed for assessing long-term performance of a disposal system. Such alternative performance measures include environmental concentrations, radionuclide fluxes and radiotoxicity. Such measures have been adopted in some regulatory regimes, but their use is not sufficiently widespread to draw definitive conclusions as to their usefulness. Alternative performance measures may be of value in developing an understanding of system performance, but stakeholders may find their use as regulatory criteria less easy to understand than measures of dose or risk. Additional work on developing a methodology for formulating and quantifying alternative performance measures is therefore suggested, together with consultation on the benefits and disadvantages associated with the adoption of such measures

Formulation and Presentation of Risk Assessments to Address Risk Targets for Radioactive Waste Disposal

Energy Technology Data Exchange (ETDEWEB)

Wilmot, R.D. [Galson Sciences Ltd, Oakham (United Kingdom)

2002-10-01

. Supporting calculations to explore these issues quantitatively could provide additional support for conducting such a review. Regulatory guidance on these issues would be a further means of supporting the review process. In addition to a review of approaches to the calculation of risk, the report also examines alternative measures that have been proposed for assessing long-term performance of a disposal system. Such alternative performance measures include environmental concentrations, radionuclide fluxes and radiotoxicity. Such measures have been adopted in some regulatory regimes, but their use is not sufficiently widespread to draw definitive conclusions as to their usefulness. Alternative performance measures may be of value in developing an understanding of system performance, but stakeholders may find their use as regulatory criteria less easy to understand than measures of dose or risk. Additional work on developing a methodology for formulating and quantifying alternative performance measures is therefore suggested, together with consultation on the benefits and disadvantages associated with the adoption of such measures.

Parameters for Pyrethroid Insecticide QSAR and PBPK/PD Models for Human Risk Assessment

Science.gov (United States)

This pyrethroid insecticide parameter review is an extension of our interest in developing quantitative structure–activity relationship–physiologically based pharmacokinetic/pharmacodynamic (QSAR-PBPK/PD) models for assessing health risks, which interest started with the organoph...

A review of regulatory risk assessment with formaldehyde as an example.

Science.gov (United States)

Imbus, H R

1988-09-01

Quantitative risk assessment may vary by over a millionfold depending upon the model used. The EPA currently uses models which project the highest potential risk. Furthermore, there is no consideration of the probability that a chemical is a human carcinogen. Such an approach may result in unrealistically high risk at exposures far below current ambient levels. In the case of formaldehyde, three alternative approaches to risk assessment are examined. One uses the maximum likelihood estimate of the multistage model, another uses the no observable adverse effect level divided by a safety factor of 100, and the third uses a probability estimate that the substance is carcinogenic at typical ambient exposures multiplied by EPA's upper bound estimate. The probability estimate is made from considerations of metabolism and pharmacokinetics, toxicology, short-term tests, animal tests, and epidemiology.

Presentation of a method for consequence modeling and quantitative risk assessment of fire and explosion in process industry (Case study: Hydrogen Production Process

Directory of Open Access Journals (Sweden)

M J Jafari

2013-05-01

 .Conclusion: Since the proposed method is applicable in all phases of process or system design, and estimates the risk of fire and explosion by a quantitative, comprehensive and mathematical-based equations approach. It can be used as an alternative method instead of qualitative and semi quantitative methods.

Quantitative weight of evidence assessment of risk to honeybee colonies from use of imidacloprid, clothianidin, and thiamethoxam as seed treatments: a postscript.

Science.gov (United States)

Solomon, Keith R; Stephenson, Gladys L

2017-01-01

This paper is a postscript to the four companion papers in this issue of the Journal (Solomon and Stephenson 2017a , 2017b ; Stephenson and Solomon 2017a , 2017b ). The first paper in the series described the conceptual model and the methods of the QWoE process. The other three papers described the application of the QWoE process to studies on imidacloprid (IMI), clothianidin (CTD), and thiamethoxam (TMX). This postscript was written to summarize the utility of the methods used in the quantitative weight of evidence (QWoE), the overall relevance of the results, and the environmental implications of the findings. Hopefully, this will be helpful to others who wish to conduct QWoEs and use these methods in assessment of risks.

Qualitative versus quantitative assessment of cerebrovascular reserve capacity

International Nuclear Information System (INIS)

Okuguchi, Taku

2000-01-01

Quantitative studies of cerebral blood flow (CBF) combined with a acetazolamide (ACZ) challenge have defined a subgroup of patients with symptomatic carotid or middle cerebral artery (MCA) occlusive diseases who are at an increased risk for stroke. Recent reports suggest that qualitative CBF techniques could also define the same high-risk subgroup. To evaluate the accuracy of the qualitative method, we compared qualitative ratios with quantitative CBF data, obtained using iodine-123-N-isopropyl-p-iodoamphetamine (IMP) single-photon emission computed tomography (SPECT). We analyzed qualitative and quantitative IMP SPECT images for 50 patients with symptomatic carotid or middle cerebral artery occlusive diseases. Quantitative CBF data were measured by the autoradiographic technique. One region-of-interest within each hemisphere was within the MCA territory. Relative cerebrovascular reserve capacity (CVRC) obtained using qualitative images before and after the intravenous administration of 1 g of ACZ was defined as follows: ( ACZ C occl / ACZ C non )/( baseline C occl / baseline C non ). The threshold for abnormal relative CVRC was defined as less than 1.0. Quantitative CBF was considered abnormal when the response to ACZ (percent change) on the symptomatic side (absolute CVRC) was a decrease of more than 10%. Of 39 patients whose relative CVRC were considered abnormal, 29 (74%) were normal in absolute CVRC (i.e., false positive). Two of 12 (17%) who were not considered compromised by qualitative criteria had abnormal absolute CVRC (i.e., false negative). This study demonstrates that this important subgroup cannot be accurately defined with qualitative methodology. (author)

Qualitative versus quantitative assessment of cerebrovascular reserve capacity

Energy Technology Data Exchange (ETDEWEB)

Okuguchi, Taku [Iwate Medical Univ., Morioka (Japan). School of Medicine

2000-06-01

Quantitative studies of cerebral blood flow (CBF) combined with a acetazolamide (ACZ) challenge have defined a subgroup of patients with symptomatic carotid or middle cerebral artery (MCA) occlusive diseases who are at an increased risk for stroke. Recent reports suggest that qualitative CBF techniques could also define the same high-risk subgroup. To evaluate the accuracy of the qualitative method, we compared qualitative ratios with quantitative CBF data, obtained using iodine-123-N-isopropyl-p-iodoamphetamine (IMP) single-photon emission computed tomography (SPECT). We analyzed qualitative and quantitative IMP SPECT images for 50 patients with symptomatic carotid or middle cerebral artery occlusive diseases. Quantitative CBF data were measured by the autoradiographic technique. One region-of-interest within each hemisphere was within the MCA territory. Relative cerebrovascular reserve capacity (CVRC) obtained using qualitative images before and after the intravenous administration of 1 g of ACZ was defined as follows: ({sub ACZ}C{sub occl}/{sub ACZ}C{sub non})/({sub baseline}C{sub occl}/{sub baseline}C{sub n}= {sub on}). The threshold for abnormal relative CVRC was defined as less than 1.0. Quantitative CBF was considered abnormal when the response to ACZ (percent change) on the symptomatic side (absolute CVRC) was a decrease of more than 10%. Of 39 patients whose relative CVRC were considered abnormal, 29 (74%) were normal in absolute CVRC (i.e., false positive). Two of 12 (17%) who were not considered compromised by qualitative criteria had abnormal absolute CVRC (i.e., false negative). This study demonstrates that this important subgroup cannot be accurately defined with qualitative methodology. (author)

Trial of risk assessment of a hypothetical nuclear facility

International Nuclear Information System (INIS)

Terao, Norichika; Suzuki, Mitsutoshi

2013-01-01

An equation for risk assessment in physical protection is shown by a probability of an adversary attack during a period time, P A , a probability of system effectiveness, P E , and consequence value, C. In addition, P E is shown as the multiplication of a probability of interruption of the facility, P I , by a probability of neutralization by response force, P N . In this study, it is assumed that an adversary assaults a hypothetical nuclear facility. The new quantification method about P A and P I in risk evaluation formula is devised, and risk assessment is attempted. In case of P A , the possibility of assaults against a nuclear facility is discussed by using terrorism data written in the open source database of terrorism, Global Terrorism Database (GTD), summarized by University of Maryland. In addition, it is discussed about P I by using the way of thinking of a risk assessment tool, EASI, developed by the Sandia National Laboratories (SNL). In the hypothetical nuclear facility, the performance of response force, sensors, and communication is expressed quantitatively by probability distribution based on some assumptions. (author)