基于动态风险平衡的海洋平台事故连锁风险研究

针对海洋平台事故风险特点,提出动态风险平衡概念,以此建立事故动力模型,并将该模型运用到墨西哥湾"深水地平线"井喷事故。动态风险平衡表征事故动力与事故阻力之间的动态平衡状态,具有动态性和暂时稳定性。事故动力模型以海洋平台可能发生的重大事故为研究对象,从工艺、技术和管理等角度分析事故可能致因和事故发展可能影响因素。该模型首先分析对象的初始事故动力,建立事故连锁风险图,然后计算初始动力发生情况下,传递动力和传递阻力的概率分布,最后提出相应风险控制措施。实例分析表明,基于动态风险平衡建立的事故动力模型能有效分析海洋平台事故连锁风险。     

A procedure for annually estimating wage losses due to accidents in the U.S.

The demand for accident cost information has increased in recent times as safety professionals seek to compare accident costs with other societal problems. Addressing one component of accident costs, this study proposes a procedure for estimating the cost of lost wages due to accidents with separate estimates generated for motor vehicle, work, home, and public accidents, as well as the overall total. Estimates were developed from data that can be updated annually so that cost estimates can be kept current. Deaths, permanent disabilities, and temporary disabilities of workers were included as part of the framework. In addition, the value of homemaker services lost due to accidents was estimated. The procedure utilized the ‘human capital’ approach, whereby the discounted present value of lost future earnings is taken as the appropriate measure of the productivity loss to society due to accidents. Other cost estimating approaches were discussed. Using this procedure, it was estimated that accidental injuries resulted in $31.1 billion in wage losses in 1985, about 1.6% of all wages and salaries paid in that year.     

Evacuation, escape, and rescue experiences from offshore accidents including the Deepwater Horizon

When a major hazard occurs on an installation, evacuation, escape, and rescue (EER) operations play a vital role in safeguarding the lives of personnel. There have been several major offshore accidents where most of the crew has been killed during EER operations. The major hazards and EER operations can be divided into three categories; depending on the hazard, time pressure and the risk influencing factors (RIFs). The RIFs are categorized into human elements, the installation and hazards. A step by step evacuation sequence is illustrated. The escape and evacuation sequence from the Deepwater Horizon offshore drilling platform is reviewed based on testimonies from the survivors. Although no casualties were reported as a result of the EER operations from the Deepwater Horizon, the number of survivors offers a limited insight into the level of success of the EER operations. Several technical and non-technical improvements are suggested to improve EER operations. There is need for a comprehensive analysis of the systems used for the rescue of personnel at sea, life rafts and lifeboats in the Gulf of Mexico.     

Management walk-arounds: Lessons from the Gulf of Mexico oil well blowout

Many companies understand that good management requires senior managers to spend time with front line workers. Some companies build into performance agreements for senior managers a requirement that they conduct a certain number of such site visits each year. The challenge is to make productive use of these visits. Safety is often a focus for visiting VIPs, but too often safety is understood to be a matter of “slips, trips and falls”, rather than the major hazards that can blow the plant or the rig apart. This paper will examine a VIP visit made to the Deepwater Horizon rig by senior managers from BP and from the rig owner, Transocean, just hours before the explosion. It will argue that, despite their best of intentions, these managers fell into the trap identified above. The paper looks at things that senior managers can do to focus attention on the most significant hazards.     

Trends in chemical hazards in Japan

In the past, the chemical industry in Japan has been the cause of a number of major industrial accidents. Subsequent to each accident, specific lessons have been learned. These lessons learned have been implemented in terms of safety education of the employees and/or safety measures of the equipment and facilities resulting in a rapid decrease of corresponding accident frequencies. In this paper, we summarized both recent and past major accidents caused by chemical substances in fixed installations in Japan. Case studies show that runaway reactions are among the main causes of major accident occurrences in the chemical process industry in Japan. A recent fatal poisoning accident caused by H₂S gas generated during maintenance work again highlights the necessity of adequate safety management in a chemical factory. Therefore, even if hazard evaluation of chemical substances and chemical processes is necessary to prevent runaway reactions, human error is also an important factor contributing to reaction hazards [Wakakura, M. (1997) Human factor in chemical accidents, J. Safety Eng. High Press. Gas. Safety Inst. Japan, 34, 846].     

Off-road truck-related accidents in U.S. mines

IntroductionOff-road trucks are one of the major sources of equipment-related accidents in the U.S. mining industries. A systematic analysis of all off-road truck-related accidents, injuries, and illnesses, which are reported and published by the Mine Safety and Health Administration (MSHA), is expected to provide practical insights for identifying the accident patterns and trends in the available raw database. Therefore, appropriate safety management measures can be administered and implemented based on these accident patterns/trends.MethodsA hybrid clustering-classification methodology using K-means clustering and gene expression programming (GEP) is proposed for the analysis of severe and non-severe off-road truck-related injuries at U.S. mines. Using the GEP sub-model, a small subset of the 36 recorded attributes was found to be correlated to the severity level.ResultsGiven the set of specified attributes, the clustering sub-model was able to cluster the accident records into 5 distinct groups. For instance, the first cluster contained accidents related to minerals processing mills and coal preparation plants (91%). More than two-thirds of the victims in this cluster had less than 5 years of job experience. This cluster was associated with the highest percentage of severe injuries (22 severe accidents, 3.4%). Almost 50% of all accidents in this cluster occurred at stone operations. Similarly, the other four clusters were characterized to highlight important patterns that can be used to determine areas of focus for safety initiatives.ConclusionsThe identified clusters of accidents may play a vital role in the prevention of severe injuries in mining. Further research into the cluster attributes and identified patterns will be necessary to determine how these factors can be mitigated to reduce the risk of severe injuries.Practical applicationAnalyzing injury data using data mining techniques provides some insight into attributes that are associated with high accuracies for predicting injury severity.     

Precursor-based hierarchical Bayesian approach for rare event frequency estimation: A case of oil spill accidents

Due to a scarcity of data, the estimate of the frequency of a rare event is a consistently challenging problem in probabilistic risk assessment (PRA). However, the use of precursor data has been shown to help in obtaining more accurate estimates. Moreover, the use of hyper-priors to represent prior parameters in the hierarchical Bayesian approach (HBA) generates more consistent results in comparison to the conventional Bayesian method. This study proposes a framework that uses a precursor-based HBA for rare event frequency estimation. The proposed method is demonstrated using the recent BP Deepwater Horizon accident in the Gulf of Mexico. The conventional Bayesian method is also applied to the same case study. The results show that the proposed approach is more effective with regards to the following perspectives: (a) using the HBA in the proposed framework provides an opportunity to take full advantage of the sparse data available and add information from indirect but relevant data; (b) the HBA is more sensitive to changes in precursor data than the conventional Bayesian method; and (c) using hyper-priors to represent prior parameters, the HBA is able to model the variability that can exist among different sources of data.     

The development of a more risk-sensitive and flexible airport safety area strategy: Part II. Accident location analysis and airport risk assessment case studies

This two-part paper presents the development of an improved airport risk assessment methodology aimed at assessing risks related to aircraft accidents at and in the vicinity of airports and managing Airport Safety Areas (ASAs) as a risk mitigation measure. The improved methodology is more quantitative, risk-sensitive, flexible and transparent than standard risk assessment approaches. As such, it contributes to the implementation of Safety Management Systems at airports, as stipulated by the International Civil Aviation Organisation.The second part of the paper presents the analysis of accident locations, including the plotting of Complementary Cumulative Probability Distributions for the relevant accident types. These were then used in conjunction with the improved accident frequency models to produce Complementary Cumulative Frequency Distributions that could be used to assess risks related to specific runways and determine Airport Safety Area (ASA) dimensions necessary to meet a quantitative target level of safety. The approach not only takes into account risk factors previously ignored by standard risk assessments but also considers the operational and traffic characteristics of the runway concerned. The use of the improved risk assessment technique and risk management strategy using ASAs was also demonstrated in two case studies based on New York LaGuardia Airport and Boca Raton Airport in Florida.     

BP墨西哥湾漏油事件应急处置与危机管理的启示

发生在2010年4月份的越洋钻探公司＂深水地平线＂钻井平台井喷爆炸着火事故,造成人员伤亡和引发墨西哥湾污染事件,被美国定为国家级灾难,损失之大、污染之重、影响范围之广,已经引起了全球的高度反思。如何从BP公司这样的跨国公司处置漏油事件过程中学习应急管理,从社会责任的展示学到危机应对,应当成为当今社会安全文化建设的重点问题。本文通过这一典型案例分析,结合历史发展的必然和应急工作的现实,提出了对＂应急与危机＂新的认识,以求得我们对安全文化建设新的思考。     

石油钻井作业的安全葡萄图管理技术

石油钻井作业是一个高风险行业,其风险具有严重性、突发性、隐蔽性、随机性的特点,是石油石化行业中最主要的事故频发区之一.震惊世界的“12.23”事故以后,在国家和企业安全生产的指导与监督下,事故较以前明显减少,但钻井作业的特点决定了其风险因素不会被消除,只能通过人的因素去预防事故发生.安全葡萄图从人的因素考虑,结合了人体生物节律与葡萄图两者的优点,除了具有葡萄图的特点外,还具有预测性、记录性和选拔性,是安全管理方面的一种新方法.安全葡萄图是一种以人为本的安全管理方法,通过加强人员安全管理来减少和消除事故隐患的目的.该方法简单实用,适合于钻井等高风险行业使用.     

Safety in the mining industry and the unfinished legacy of mining accidents: Safety levers and defense-in-depth for addressing mining hazards

Mining remains one of the most hazardous occupations worldwide and underground coal mines are especially notorious for their high accident rates. In this work, we provide an overview of the broad and multi-faceted topic of safety in the mining industry. After reviewing some statistics of mining accidents in the United States, we focus on one pervasive and deadly failure mode in mines, namely explosions. The repeated occurrence of mine explosions, often in similar manner, is the loud unfinished legacy of mining accidents and their occurrence in the 21st century is inexcusable and should constitute a strong call for action for all stakeholders in this industry to settle this problem. We analyze one such recent mine disaster in which deficiencies in various safety barriers failed to prevent the accident initiating event from occurring, then subsequent lines of defense failed to block this accident scenario from unfolding and to mitigate its consequences. We identify the technical, organizational, and regulatory deficiencies that failed to prevent the escalation of the mine hazards into an accident, and the accident into a “disaster”. This case study provides an opportunity to illustrate several concepts that help describe the phenomenology of accidents, such as initiating events, precursor or lead indicator, and accident pathogen. Next, we introduce the safety principle of defense-in-depth, which is the basis for regulations and risk-informed decisions by the US Nuclear Regulatory Commission, and we examine its relevance and applicability to the mining system in support of accident prevention and coordinating actions on all the safety levers, technical, organizational, and regulatory to improve mining safety. The mining system includes the physical confines and characteristics of the mine, the equipment in the mine, the individuals and the organization that operate the mine, as well as the processes and regulatory constraints under which the mine operates. We conclude this article with the proposition for the establishment of defense-in-depth as the guiding safety principle for the mining industry and we indicate possible benefits for adopting this structured hazard-centric system approach to mining safety.     

The effectiveness of U.S. OSHA process safety management inspection – A preliminary quantitative evaluation

This study attempted to evaluate the inspection effectiveness of the U.S. OSHA process safety management (PSM) standard using statistical correlation test. A total of 6578 citations of past 1277 OSHA PSM inspections from 1992 to 2006 were quantitatively compared with the findings of the U.S. Chemical Safety and Hazard Investigation Board (CSB) investigations on root and contributing causes of 19 major chemical accidents. Nonparametric Spearman's coefficient of rank correlation tests showed a moderately strong agreement between OSHA PSM inspection citations and CSB findings at p < .01 significant level, and the degree of agreement increased with time. These results suggested that past OSHA PSM inspections had cited the problems that were the accident root causes, and the effectiveness of PSM citations has been improved as more inspections were conducted since the standard promulgation. However, factors such as standard coverage, inspection frequency, inspection resources allocation, and inspection strategy, were critical for effective PSM standard enforcement and implementation. Future studies should include more aspects of PSM citations and CSB accident investigation data for better evaluation of inspection effectiveness. The results may be valuable to the PSM enforcement policy makers.     

Technical note on the contribution of sociotechnical factors to accidents notified to MARS

Not least due to the new `Seveso II Directive', Safety Management Systems (SMS) have become a hot topic in the `safety business'. To reveal in a structured way how organisations manage safety at their plants, classification schemes can be applied to identify plant-specific precautions on different hierarchical levels, e.g. from `top level' equipment reliability to `bottom level' safety climate. In this paper, such a model is used to classify the accidents reported to the European Commission's Major Accident Reporting System (MARS) according to the levels on which failures resulting in actual accidents did occur, and to cross-compare the levels of causation with the overall `severity' of the accidents. It is analytically shown that ∼66% of the accidents are caused by latent SMS failures, and that especially those accidents which are caused by failures in the `deepest layers of latency' have significantly higher `severities' than accidents caused by more `immediate' failures. In other words, it is quite likely that the deeper the underlying causes of an accident, the more `severe' its consequences. Implementing SMS is thus worth the effort.     

中国民航行业可接受的安全水平研究

中国民航局提出持续安全理念,并正在制定国家航空安全方案,推动行业安全管理由目前基于规章符合性的安全监管逐渐转向规章符合性基础上的安全绩效监管,其中一项重要的工作是设定中国民航业可接受的安全水平,来衡量民航业是否满足持续改进安全的目标的要求。本文根据国际民航组织对可接受安全水平的设定指南,同时参考国外民航常用的事故指标,设计了一套中国民航行业可接受安全水平的指标体系,该指标体系包括安全评估指标、安全绩效评估指标和安全指数三层,并对该指标体系内事故率指标和事故征候率指标设定了未来10年的目标值。该指标体系及其目标值的设定不仅可作为衡量民航是否持续安全的标准,也可为航空运输企业设定自身的安全绩效考核指标提供参考。     

The development of a more risk-sensitive and flexible airport safety area strategy: Part I. The development of an improved accident frequency model

This two-part paper presents the development of an improved airport risk assessment methodology aimed at assessing risks related to aircraft accidents at and in the vicinity of airports and managing airport safety areas (ASAs) as a risk mitigation measure. The improved methodology is more quantitative, risk-sensitive, flexible and transparent than standard risk assessment approaches. As such, it contributes to the implementation of Safety Management Systems at airports, as stipulated by the International Civil Aviation Organisation.The first part of the paper presents the methodological advances made in the development of accident frequency models; namely the building of a single comprehensive database of all relevant accident types, the collection and use of normal operations data in quantifying the criticality of a series of risk factors, and modelling accident frequency using multivariate logistic regression. The resulting models have better goodness-of-fit, sensitivity and specificity than standard risk assessment methodologies.     

A capping technique for emergency response in offshore blowout accidents

Capping stack is an emergency shut-in technique that can effectively control offshore blowout accidents. This technique stemmed the spilled oil well (Macondo) in 2010 Deepwater Horizon blowout accident. However, few efforts have been devoted to studying the way to efficiently and safely conduct the operation of capping stack. In this paper, program evaluation and review technique (PERT) was employed to quantitatively design the operation procedure of capping stack. A mechanical model was established to determine the configuration scheme of capping stack. And a sensitivity analysis of operational factors of capping stack was conducted through orthogonal tests. Experimental results recommend to optimize the operation process by reducing the working time of diamond cutting tool down-pass, Lower Marine Riser Package (LMRP) upper riser incision, LMRP and original Blowout Preventer (BOP) separation, and LMRP recovery, in order to guarantee that the whole operation can be completed as scheduled. The results show that the number of ram BOPs has little effect on the equivalent stress of conductors. To improve system reliability, a five-ram capping stack is recommended to be applied in the defined accident scenario. The maximum equivalent stress of conductors rates the drilling vessel offset as the primary factor, followed by shut-in pressure, ocean current and top tension. The drilling vessel offset needs to be given the priority control and the shut-in pressure should be jointly monitored.     

Analysis of work related accidents in the Spanish mining sector from 1982-2006

Introduction

The rate for work related accidents in the Spanish mining sector is notably higher than in other countries such as the United States. It produces a very negative impact on the mining industry. This paper is the report of a study on serious and fatal accidents in Spanish mining from 1982-2006. It is based on the reports of 212 accidents (serious or fatal) carried out by the General Management of Energy and Mining of Catalonia (Spain). Method: The high work-related accident rate in the Spanish mining sector makes it necessary to carry out an analysis and research that can shed light on the causes of this high rate; this is the only way that a solution can be found. The study is based on Feyer and Williamson's analysis of accident causes, as they apply to 212 accidents. The types and causes of the accidents are coded according to the coding system used by the Spanish National Institute for Safety and Hygiene in the Workplace, which allows us to identify a series of direct causes and contributing factors in different accidents. Results If all the causes and factors that are present in the accidents are known, we are able to look for appropriate solutions to reduce them as much as possible. In short, we are able to come up with a series of conclusions that expose the weak links in the management of accident prevention in companies. This is helpful in the struggle to reduce work injuries in the Spanish mining sector.     

Modelling of BP Texas City refinery accident using dynamic risk assessment approach

Process industries involve handling of hazardous substances which on release may potentially cause catastrophic consequences in terms of assets lost, human fatalities or injuries and loss of public confidence of the company. In spite of using endless end-of-the-pipe safety systems, tragic accidents such as BP Texas City refinery still occur. One of the main reasons of such rare but catastrophic events is lack of effective monitoring and modelling approaches that provide early warnings and help to prevent such event. To develop a predictive model one has to rely on past occurrence data, as such events are rare, enough data are usually not available to better understand and model such behavior. In such situations, it is advisable to use near misses and incident data to predict system performance and estimate accident likelihood. This paper is an attempt to demonstrate testing and validation of one such approach, dynamic risk assessment, using data from the BP Texas City refinery incident.Dynamic risk assessment is a novel approach which integrates Bayesian failure updating mechanism with the consequence assessment. The implementation of this methodology to the BP Texas City incident proves that the approach has the ability to learn from near misses, incident, past accidents and predict event occurrence likelihood in the next time interval.