基于前导事件和贝叶斯网络的储罐溢油动态风险评价

部分高风险危化品企业搬迁改造困难重重,为控制风险、保护周围人民生命和财产安全,有必要建立动态风险评价系统,对事故发生概率进行监控和预测。采用贝叶斯网络对事故发生概率进行定量分析。先在利用蝴蝶结模型辨识事故原因和后果的基础上,将其转化为贝叶斯网络模型;再导入"前导事件"信息和先验概率推导后验事故发生概率,量化分析事故发生随时间的变化概率;最后,以储罐溢流场景为例进行动态风险计算,结果表明,随化工装置生产时间和"前导事件"增长,元件失效概率和事故风险呈显著增长趋势。因此建议企业应重视"前导事件"并采取措施减少"前导事件",如优化检维修方案、及时更换关键部件、进行全面的事故调查等。     

航空维修系统危险源识别和风险分析方法

针对目前航空维修单位风险管理工作中普遍遇到的如何全面、规范、准确地识别危险源,如何科学计算和评价风险问题,提出一种危险源识别方法和风险分析方法.首先,设计维修系统的危险源引导词,并给出危险源描述方法和识别流程,以规范识别危险源;然后,设计危险源导致潜在不良后果引导词,在引导词的指引下确定危险源的所有潜在不良后果;最后,利用模糊综合评价法计算危险源导致潜在不良后果的风险.以某维修单位新增设备为例进行了危险源识别和风险计算工作,结果表明:该方法能够快速、全面、规范地找到危险源和危险源潜在不良后果,能够更为科学地计算风险,为进一步风险控制奠定基础.本方法力图使风险管理工作规范有效,并为行业内风险数据积累和分享、数据分析与预测等奠定基础.     

Risk-mitigating beliefs,risk estimates,and self-reported speeding in a sample of Australian drivers

PROBLEM: Research suggests that people who engage in risk-taking behaviors often hold specific beliefs that can mitigate or reduce their perceptions of risk associated with those behaviors. METHOD: A scale was developed (Speeding Risk Belief Scale (SRBS)) to assess beliefs about speeding-related risk and predict self-reported speeding in a random-digit telephone survey of 800 South Australian drivers between the ages of 16 and 50. RESULTS: The scale was internally consistent, and path analyses showed it to be associated with self-reported speeding, both directly and indirectly through participants' estimates of speeding-related risk. DISCUSSION: Origins of risk-mitigating beliefs and the extent to which they may be causally linked with speeding are discussed, and recommendations are made for future research. IMPACT ON INDUSTRY: This research has strong implications for the conduct of countermeasure campaigns that disseminate information on speeding-related risk.     

Dynamic risk assessment using failure assessment and Bayesian theory

To ensure the safety of a process system, engineers use different methods to identify the potential hazards that may cause severe consequences. One of the most popular methods used is quantitative risk assessment (QRA) which quantifies the risk associated with a particular process activity. One of QRA's major disadvantages is its inability to update risk during the life of a process. As the process operates, abnormal events will result in incidents and near misses. These events are often called accident precursors. A conventional QRA process is unable to use the accident precursor information to revise the risk profile. To overcome this, a methodology has been proposed based on the work of Meel and Seider (2006). Similar to Meel and Seider (2006) work, this methodology uses Bayesian theory to update the likelihood of the event occurrence and also failure probability of the safety system. In this paper the proposed methodology is outlined and its application is demonstrated using a simple case study. First, potential accident scenarios are identified and represented in terms of an event tree, next, using the event tree and available failure data end-state probabilities are estimated. Subsequently, using the available accident precursor data, safety system failure likelihood and event tree end-state probabilities are revised. The methodology has been simulated using deterministic (point value) as well as probabilistic approach. This Methodology is applied to a case study demonstrating a storage tank containing highly hazardous chemicals. The comparison between conventional QRA and the results from dynamic failure assessment approach shows the significant deviation in system failure frequency throughout the life time of the process unit.     

Incidence rates and risk factors for injury events in high school students in Lijin County, China

PROBLEM: Most investigations of injuries among Chinese populations are focused on urban or better developed areas, fewer on rural or poor areas. METHODS: From September 21 to 27, 2002, an epidemiological investigation of eight kinds of injury-related events was carried out among 1,944 students in 39 classes randomly sampled from middle schools in Lijin County, a rural area. The eight kinds of events were: (a) traffic accidents, (b) poisoning, (c) fall, (d) burn or scald, (e) blunt or sharp tools contact, (f) electrical contact, (g) animal or insect bites, and (h) non-fatal drowning. RESULTS: The total incidence rate of eight kinds of injuries in the previous year was 21.1%. The incidence rate among boys was 24.2%, while that among girls was 17.4%, which was significant (chi-square=13.4, P<0.05). The incidence rate among junior high school students was 23.1%, while that among senior high school students was 15.5%, which was also significant (chi-square=13.2, P<0.05). A case-control study of 410 students with at least one of eight kinds of injury events indicated that students' gender and their mothers' health status were related to their injuries. CONCLUSION: The injury incidence rate in a rural area was less than other results in urban or developed areas. Students' gender and mothers' health status were important factors associated with the occurrence of injury. IMPACT ON INDUSTRY: In order to improve the surroundings of the growing population of adolescents, some preventive measures should be put forward, especially to the high-risk students of injury.     

Industrial disasters: Extreme events,extremely rare. Some reflections on the treatment of uncertainties in the assessment of the associated risks

This paper addresses the issue of risk from disasters occurring due to accidents in high-consequence technologies, e.g., nuclear and oil and gas. The focus is on the challenges posed to the representation and treatment of uncertainties in the assessment of such risk, given that the occurrence of such extreme disasters is extremely unlikely, and yet they occur. A general framework of analysis is proposed.     

基于动态贝叶斯网络分析法的炸药库爆炸事故分析

炸药库一旦发生燃烧爆炸事故,影响将非常恶劣,因此,以其特殊性和危险性成为安全工作的重点.在已有的对炸药库的爆炸事故进行事故树分析法(FTA)定性分析的基础上,采用贝叶斯网络转化的方法,结合优先或门、顺序相关门等动态逻辑门进行爆炸事故树的动态贝叶斯网络转化,建立了相应的动态贝叶斯网络模型,进行了定量的事故分析并得出结论.     

在“四早”原则基础上 建议加个“早研判”

新冠肺炎疫情爆发以来,各地各部门落实早发现、早报告、早隔离、早治疗的"四早"原则。国家减灾委专家委副主任、国务院应急管理专家组组长闪淳昌建议,在"四早"原则基础上还应加个"早研判",将"五早"原则贯穿在应对突发事件的全过程。     

Working conditions,psychological/physical symptoms and occupational accidents. Bayesian network models

Each day thousands of workers suffer occupational accidents of varying degrees of severity. Accidents at work render workers incapable of carrying out their day to day activities, either temporarily or permanently, and they also have detrimental effects on family life, the company, and the general public. In order to reduce the occupational accident rate, it is necessary to determine the causes of those accidents. Although there are many different types of accidents, they generally stem from poor working conditions. The purpose of this study was to analyze the influence of working conditions on occupational accidents from data gathered in the VI National Survey of Working Conditions (VI NSWCs) in 2007. This survey utilized a random sample of the active population of Spain. The sample comprised 11,054 people (5917 males and 5137 females). In order to carry out the study, a probabilistic model was built using Bayesian networks. The model included the following variables: hygiene conditions, ergonomic conditions, job demands, physical symptoms, psychological symptoms, and occupational accidents. The study demonstrated that there were strong relationships between hygiene conditions and occupational accidents; it has been shown that poor hygienic conditions duplicate the probability of accident. Physical symptoms increased almost 50% due to poor ergonomic conditions. And finally, high job demands almost duplicated the psychological symptoms. The investigation also showed a high degree of interdependence between physical and psychological symptomatologies and the relationship between these and occupational accidents.     

Utility estimates of job performance as related to the Data,People, and Things parameters of work

The purpose of this study was to investigate the applicability of the Schmidt–Hunter global estimation method of assessing utility across a broad range of jobs. Ninety-five industrial/organizational psychologists estimated the utility of performance in 24 carefully selected jobs. The utility estimates were compared to the Data, People, and Things worker function parameters from the Dictionary of Occupational Titles. The majority of jobs (62.5 per cent) produced significantly positively skewed distributions of dollar-valued job performance. The Data, People, and Things parameters accounted for 46 per cent of the variance in the non-symmetry of the utility distributions and 33 per cent of the variance in the inter-rater reliability of the utility estimates. The implications of the results were discussed for utility assessment, and explained from a decision theoretic perspective. © 1998 John Wiley & Sons, Ltd.     

Bayesian networks make LOPA more effective,QRA more transparent and flexible,and thus safety more definable!

Quantitative risk analysis is in principle an ideal method to map one’s risks, but it has limitations due to the complexity of models, scarcity of data, remaining uncertainties, and above all because effort, cost, and time requirements are heavy. Also, software is not cheap, the calculations are not quite transparent, and the flexibility to look at various scenarios and at preventive and protective options is limited. So, the method is considered as a last resort for determination of risks. Simpler methods such as LOPA that focus on a particular scenario and assessment of protection for a defined initiating event are more popular. LOPA may however not cover the whole range of credible scenarios, and calamitous surprises may emerge.In the past few decades, Artificial Intelligence university groups, such as the Decision Systems Laboratory of the University of Pittsburgh, have developed Bayesian approaches to support decision making in situations where one has to weigh gains and costs versus risks. This paper will describe details of such an approach and will provide some examples of both discrete random variables, such as the probability values in a LOPA, and continuous distributions, which can better reflect the uncertainty in data.     

Differences in risk perception,priorities, worry and demand for risk mitigation in transport among Norwegians in 2004 and 2008

The present study aimed to investigate differences in risk perception, the demand for risk mitigation, priorities and worry related to transport among the Norwegian public in 2004 and 2008. Age, gender, education, driver licence and number of injuries in transport were controlled for. The comparison was carried out with questionnaire surveys among representative samples of the Norwegian public in 2004 (n = 1730) and 2008 (n = 1864). The results showed that the perceived probabilities of transport accidents decreased, whereas the perceived severity of consequences increased during this period. Both samples estimated higher probabilities of accidents by private means of transport. The demand for risk mitigation and priorities related to transport safety increased significantly in the same period. The 2008 sample also reported more worry regarding accidents by private transport. Results were discussed in relation to transport safety campaigns, safety measures and significant accidents which occurred in this period.     

Cross-cultural comparisons of traffic safety,risk perception,attitudes and behaviour

The core aim of the present study is to examine cultural differences in risk perception and attitudes towards traffic safety and risk, taking behaviour in the Norwegian and the Ghanaian public. An additional aim is to discuss the applicability of various traffic measures, suited for low and middle income countries in Africa.Sample: The results of the present study are based on two self-completion questionnaire surveys carried out in February and March 2006. The first was a representative sample of the Norwegian public above 18 years of age (N = 247). The second was a stratified sample of Ghanaian respondents (N = 299). In Ghana the data was collected in Accra and Cape Coast.The results showed that there is potential for further improvement of safety attitudes and risk behaviour among Ghanaians as well as Norwegians. There were also differences in the respondents’ evaluation of attitudes, risk perception and behaviour. Perceived risk and attitudes also significantly predicted risk behaviour and accidents/collisions. The implications of these results for traffic safety will be discussed.     

The relationship between recruitment processes, familiarity, trust, perceived risk and safety

Introduction and Method

Participants′ perceptions of the safety-related aspects of their organization′s recruitment processes were examined, as were their perceptions of safety aspects associated with new recruits.

Results

One hundred and fifty-four professional fire fighters indicated the trust they held in the safety-related aspects of their organizations′ selection and pre-start training. Perceived trust in pre-start training was negatively correlated (r = -.24, p < .01) with the risk associated with new recruits, and positively correlated (r = .50, p < .01) with ratings of trust in recruits to immediately work safely. Furthermore, trust in recruits to immediately work safely was negatively correlated (r = -.21, p < .01) with crews′ safety behavior toward recruits.

Conclusions

These results are interpreted as particularly dangerous for workers, as new recruits lack familiarity with aspects of their new workplace that cannot be addressed by either selection or pre-start training, making them a risk.

Impact on Industry

Organizations should actively identify new recruits, and encourage existing team members not to immediately trust new recruits to work safely.     

Work-safety tension, perceived risk, and worker injuries: a meso-mediational model

IntroductionWork-safety tension arises when workers perceive that working safely is at odds with effectively doing their jobs. We proposed that workers’ perceptions of work-safety tension would be associated with higher levels of perceived risk, which would, in turn, relate to worker injuries on the job.MethodGrocery store workers (n = 600) completed an online survey and organizational worker injury reports were obtained for a two-year period following the survey. Survey results were linked to subsequent worker injuries using hierarchical generalized linear modeling.ResultsWe found support for the proposed meso-mediation model: department work-safety tension predicted subsequent worker injuries, partially through an association with workers’ risk perceptions.ConclusionsSafety researchers and consultants and organizational leaders should look beyond typically-examined safety climate constructs, such as management commitment to safety, and pay particular attention to workers’ perceptions of work-safety tension.     

Heavy trucks, conspicuity treatment, and the decline of collision risk in darkness

IntroductionThe influence of amendments to Federal Motor Vehicle Safety Standard (FMVSS) 108, requiring conspicuity treatments on heavy tractors and trailers, was determined in analyses of the odds of fatal collisions in darkness.MethodComparisons were made between crashes in which conspicuity treatment was likely relevant, and those in which it was likely irrelevant.ResultsOver 23 years, the odds that a fatal collision involving a heavy truck occurred in darkness declined by 58% among relevant crashes, while little decline was observed for irrelevant crashes. Disaggregation into crash types revealed the largest declines occurred in fatal rear-end and angle collisions. A parallel analysis of light vehicles also found declines but no differences among crash type. Similar trends were also observed for nonfatal rear end collisions.ConclusionThe results suggest that detection failure may have contributed to the risk of striking a tractor-semitrailer in darkness, and that conspicuity treatments have reduced this risk.Impact on IndustryConspicuity treatments appear to reduce risk of collision into heavy trucks in darkness. It is likely that this benefit would also extend to other vehicles that are not included in the FMVSS 108 regulation (e.g., buses, single unit trucks, recreational vehicles), although many are so equipped, regardless of the regulation.     

The impact of risk tolerance,risk perception and hazardous attitude on safety operation among airline pilots in China

The present study integrates personality approach and social cognition approach to investigate the relationships between risk tolerance, risk perception, hazardous attitude and safety operation behavior in order to understand the mechanisms underlying pilots’ safety operation behavior in aviation. The study sample consisted of 118 commercial airline pilots from China Southern Airlines Ltd. The results show risk tolerance displays an indirect effect on safety operation behavior through influencing hazardous attitude; risk perception has a significant moderating effect on the relationship between risk tolerance and safety operation behavior. Based on the above, it can be concluded that the low risk tolerance primarily influences safety operation behavior indirectly through affecting hazardous attitude. With risk perception increasing, the negative effects of risk tolerance on safety operation behavior are gradually reduced. Practical implications for aviation safety campaigns are also discussed.