Method for identifying contributors to chemical process accidents

The paper presents a new method for identifying contributors to chemical process accidents by exploiting knowledge on causes of past accident cases. Accident reports from the Failure Knowledge Database were analyzed and utilized for hazard identification. The accident information gathered was used as a basis to develop an accidents ranking and points-to-look-for approach for the safe design and operation of chemical process equipment. In the method, accident contributors including technical, design and operation errors of major process equipment types and piping are identified. The method is applicable throughout the process lifecycle, even for process changes in the early design stages. The Bhopal tragedy is used as a case study to demonstrate and test the method. The proposed method can predict on average up to 85% of accident causes and design and operation errors.     

A study of maintenance-related major accident cases in the 21st century

This paper is based on a review of 183 detailed, major accident investigation and analysis reports related to the handling, processing and storage of hydrocarbons and hazardous chemicals over a decade from 2000 to 2011. The reports cover technical, human and organizational factors. In this paper, the Work and Accident Process (WAP) classification scheme is applied to the accident reports with the intention of investigating to what extent maintenance has been a cause of major accidents and what maintenance-related causes have been the most frequent.The main objectives are: (1) to present more current overall statistics of maintenance-related major accidents, (2) to investigate the trend of maintenance-related major accidents over time, and (3) to investigate which maintenance-related major accident causes are the most frequent, requiring the most attention in the drive for improvement.The paper presents statistical analysis and interpretation of maintenance-related major accidents’ moving averages as well as data related to the types of facility, hazardous substances, major accidents and causes. This is based on a thorough review of accident investigation reports.It is found that out of 183 major accidents in the US and Europe, maintenance was linked to 80 (44%) and that the accident trend is decreasing. The results also show that “lack of barrier maintenance” (50%), “deficient design, organization and resource management” (85%) and “deficient planning/scheduling/fault diagnosis” (69%) are the most frequent causes in terms of the active accident process, the latent accident process and the work process respectively.     

Origin of equipment design and operation errors

The paper discusses the origin of chemical process equipment accidents by analyzing past accident cases available in the Failure Knowledge Database (FKD). The design and operation errors of the process equipment that caused the accidents were analyzed together with their time of occurrence. It was found that design errors contributed to 79% of accidents while the rest were only due to human and organizational errors in the operation stage and external factors. The most common types of errors were related to layout, organizational errors in the operation stage, considerations of reactivity and incompatibility, and wrongly selected process conditions (each approx. 13% of total accident contributors). On average there were about 2 design errors per accident. The timing of the errors was quite evenly distributed between various lifecycle stages. Nearly half (47%) of the errors were made in process design-oriented stages, one fourth (26%) in detailed engineering, and one fifth (20%) in operation. In addition, the most frequent design and operation errors for each equipment type were identified. A points-to-look-for list was created for each equipment type, showing also the typical time of occurrence of the error. The knowledge of type and timing of design errors can be utilized in design to focus the hazard analysis in each stage on the most error-prone features of design.     

The significance of domino effect in chemical accidents

A historical survey was performed on 330 accidents involving domino effect, occurred in process/storage plants and in the transportation of hazardous materials; only accidents occurred after 1st-January-1961 have been considered. The main features – geographical location, type of accident, materials involved, origin and causes, consequences, domino sequences – were analyzed, with special consideration to the situation in the developing countries and compared to those from other previous surveys. Among the involved substances, LPG was the most frequent one, followed by liquid hydrocarbons. Process plants (38.5% of cases) and storage areas (33%) were the most common settings; 10.6% of past domino accidents occurred in transfer operations. The ratio between “two-step” and “three-step” domino accidents was found to be 6. A specific analysis of the accidents (84) occurred in the 21st century was performed, comparing them with the total set of accidents. Finally, a set of specific recommendations inferred from the results is provided.     

基于事故统计分析的地铁运营安全管理研究

为了预防和减少地铁运营事故的发生,本文通过统计分析某城市地铁5年的运营事故资料,探讨了地铁运营事故的发生规律,从人、机、环、管几个方面分析了导致地铁运营事故发生的主要原因。结果显示:统计年度内地铁运营事故年度总量较为平稳,事故的发生对月份变化敏感度较低,受气象条件影响较小;信号故障、车辆故障是发生最频繁的事故类型,合计占事故总数的56%。事故原因分析显示,设备设施因素导致的事故占事故总数的87%;人为因素导致的事故占事故总数的7%。根据地铁运营事故特点,从人、机、环、管4方面提出了相应的安全管理对策,可为制定科学合理的地铁运营安全管理措施提供依据。     

Process industry accidents in Sri Lanka: Analysis and basic lessons learnt

Accidents in the process industry could be prevented or reduced by having good safety management measures. Such preventive measures could be further improved through the experiences and lessons learnt from past accidents. Therefore, analysis results of past accidents are valuable sources of information for determining root causes and as case material to prevent and reduce the adverse consequences of accidents in the process industry.This paper looks at accidents in the process industry that have occurred in the past 10 years from 1997 to 2006 in Sri Lanka to gain an understanding of the nature and consequences of accidents. Lessons and main areas of concern to improve safety in the Sri Lanka process industry are discussed. The analysis is done for different event types based on specific operating process stage during which the accident occurred such as processing, loading and unloading, repair and maintenance and storage, the immediate effect types such as fire, explosion, chemical releases and emissions and the consequences of each accident. Fire incidents were observed in 38 accidents analyzed. The results show that the highest number of accidents has occurred during processing operations followed by accidents during maintenance and repair work. The cause analysis shows that many accidents have occurred due to technical and human failures.The accidents are then classified according to the severity of the consequences in order to compare the nature of accidents experienced in Sri Lanka with respect to accidents in other countries in the world.     

Accident prevention approach throughout process design life cycle

The accident rate in the chemical process industry (CPI) has not been decreasing although majority of accident causes have been identified and could have been prevented by using existing knowledge. These recurring accidents show that the existing knowledge has not been used effectively. In this paper, accident knowledge learned from earlier accident analyses are utilized to predict the common design errors during chemical plant design. An accident prevention approach throughout process design life cycle is proposed for a safer design consideration where designers are guided to identify common design errors, accident contributors and critical points to look for. The accident prevention approach has been applied to analyze the BP Texas City Refinery Explosion and Fire tragedy.     

A study of storage tank accidents

This paper reviews 242 accidents of storage tanks that occurred in industrial facilities over last 40 years. Fishbone Diagram is applied to analyze the causes that lead to accidents. Corrective actions are also provided to help operating engineers handling similar situations in the future. The results show that 74% of accidents occurred in petroleum refineries, oil terminals or storage. Fire and explosion account for 85% of the accidents. There were 80 accidents (33%) caused by lightning and 72 (30%) caused by human errors including poor operations and maintenance. Other causes were equipment failure, sabotage, crack and rupture, leak and line rupture, static electricity, open flames etc. Most of those accidents would have been avoided if good engineering have been practiced.     

Protecting atmospheric storage tanks against vacuum collapse

Vacuum collapse causes many accidents involving equipment with low pressure ratings such as atmospheric storage tanks and bins. This paper presents methods to establish the appropriate relief capacities and specify pressure relief devices to protect atmospheric storage tanks and other similar equipment against this hazard. Calculations are based on simple heat balance and fluid flow calculations.     

Fired equipment combustion chamber accidents: A historical survey

A historical analysis was carried out on 189 accidents that occurred in gas and oil fuel fired equipment. The variation of frequency as a function of time, the main causes leading to a fire or an explosion, as well as the consequences of the accidents were studied. Explosion was the most frequent accident, followed by fire; in a few cases the final outcome was a release. Accidents in gas fired combustion equipment were significantly more frequent than those in the liquid fired ones. The main causes were tube rupture and/or error in ignition/reignition sequences, followed by loss of flame in the combustion chamber and, with a minor frequency, entrance of non-expected fuel and presence of non-combusted materials. The consequences on people were much more important in case of explosions than in case of fires. Even though the equipment involving combustion chambers can be considered essentially safe, this historical analysis has shown that accidents continue to occur with certain frequency because the number of existing units is quite high and the possibility of human error during its operation and maintenance is still significant.     

聚乙烯醇罐区火灾爆炸事故树分析

通过现场的调研与事故树分析相结合的手段对某厂聚乙烯醇车间聚合罐区火灾爆炸事故的危险因素进行了识别与分析.以该罐区可能发生的火灾爆炸事故作为顶上事件,对可能引发顶上事件的21个基本事件及一个条件事件构建事故树,利用最小割集、最小径集及结构重要性计算手段进行事故风险程度分析,从而确定醋酸乙烯暴聚是聚合罐区的首要危险源,而促发醋酸乙烯暴聚的物料长时间停留、气相氧含量过高、温度控制失效、阻聚剂含量不足等四个基本事件是导致聚合罐区火灾爆炸事故的最危险因素.本文对以上聚合罐区发生火灾爆炸事故的风险因素进行详细定性分析,并在此基础上有针对性的提出了相应的安全预防控制措施.同时,该聚合罐区的事故树分析结论也可以为同类别化工单位罐区的日常运行、设计改造、维护保养等工作提供理论依据.     

2006-2010年我国危险化学品事故统计分析研究

本文基于＂十一五＂期间我国危险化学品事故统计数据,从事故类别、事故发生区域、事故发生时间、企业经济类型、危险化学品类别、危险化学品事故发生环节等方面进行分析,结果表明,中毒与窒息事故和爆炸事故占危险化学品事故主要类型,易燃液体、易燃气体、爆炸品和腐蚀性物质是引发危险化学品事故的主要危险物质类型,生产环节是事故发生的主要环节,违反操作规程或劳动纪律与设备设施工具附件有缺陷是导致事故的重要原因。从落实企业安全生产主体责任、提升本质安全化水平、开展重大危险源普查、建立安全监管网络、加强危险化学品产业布局、提高事故应急救援能力等方面提出了预防和控制危险化学品事故的对策建议。     

某储罐区火灾多米诺效应场景推演

化工园区中危险源众多,一旦发生事故很容易在整个园区内蔓延和发展.针对化工园区内储罐密集,容易引发连锁反应导致事故扩大的特点,利用FDS软件对储罐火灾场景进行数值模拟,根据储罐所受热辐射确定化工园区内储罐火灾最可能的事故发生序列,并引入基于设备失效前时间的机械设备故障概率模型对罐区内单个储罐的火灾风险进行研究,得到储罐区...     

危险化学品仓储事故演化规律及消防力量需求研究

危险化学品仓储火灾事故复杂,处置难度大,易引发事故多米诺效应,对人民的生命和财产造成严重威胁。本文分析了危化品仓储火灾爆炸事故的演化规律和事故风险,结合事故案例剖析危化品仓储火灾爆炸事故后果及对周边区域的影响。针对危险化学品仓储火灾爆炸事故,建立危化品仓储火灾扑救泡沫需求评价二级指标体系,采用模糊层次分析法建立了泡沫灭火剂用量评价数学模型,并根据救援力量类别需求、各种应急救援装备与作战人员需求建立危化品火灾消防力量需求预测模型,准确预测危化品仓储事故消防力量需求。     

Causation of Severe and Fatal Accidents in the Manufacturing Sector

The main purpose of this paper is to identify the most frequent causes of accidents in the manufacturing sector in Andalusia, Spain, to help safety practitioners in the task of prioritizing preventive actions. Official accident investigation reports are analyzed. A causation pattern is identified with the proportion of causes of each of the different possible groups of causes. We found evidence of a differential causation between slight and non-slight accidents. We have also found significant differences in accident causation depending on the mechanism of the accident. These results can be used to prioritize preventive actions to combat the most likely causes of each accident mechanism. We have also done research on the associations of certain latent causes with specific active (immediate) causes. These relationships show how organizational and safety management can contribute to the prevention of active failures.     

石油化工企业生产装置静电事故分析与对策

石油化工静电事故主要与特殊介质的处理（如污油、污水、粗油、混合油等）,特殊环境或特殊工艺过程物料的处理（如设备检修或开停车期间的物料处理）等密切相关。以近十年石油化工装置发生的一些典型事故为背景,论述了石油化工企业生产装置静电事故的特点,通过典型事故的分析,提出应对措施和策略有设计不足往往是事故频发的源头;在危险暴露频率较高和风险要求较高场所,建议增设静电消除辅助设备;结合工装特点,在设备改造时适当兼顾设备的防静电技术改造,有时可以收到事半功倍的效果;编制生产装置特殊作业场所防静电规定,是抑制当前静电事故趋势的重要举措。     

Scenario deduction of Natech accident based on dynamic Bayesian network: A case study of landslide accident in a liquor storage tank area in Guizhou Province,China

Industrial technical accidents caused by natural disasters are defined as Natech accidents, such as earthquakes and landslides, which can cause tremendous damage to industrial storage tanks, and lead to accidental leakage and even serious fire and explosion accidents. In this study, a landslide-induced storage tank accident model under earthquake disasters was proposed, and the relationship between landslide mass impact and target impact resistance was taken into account. Also, tank failure and the formation of the pool fire were considered to be the consequences of the Natech accident. Through scenario deduction, the dynamic process of landslide Natech was transformed qualitatively into a disaster chain network diagram composed of a scenario state, a disaster-causing factor and emergency management. The Bayesian network was used to learn and deduce the parameters of the network diagram, and in this process, the prior probability and conditional probability of nodes were obtained primarily by Monte Carlo simulation, and by an improved expert scoring method based on the fuzzy set theory. Through visualization software, the sensitivity analysis of landslide Natech was achieved. Finally, a case study of a liquor storage tank area in Guizhou Province, China was carried out, and the results show that a large amount of hazardous material leakage caused by buckling is key to the formation of pool fire accidents, and several prevention measures for earthquake-induced landslide Natech was proposed according to the sensitivity analysis.     

事故树-风险矩阵评估高校实验室火灾风险

为了使高校实验室安全管理科学化、精准化,应用事故树-风险矩阵法进行风险评估。首先采用事故树法对实验室火灾事故进行分析,得出导致事故发生的基本事件,然后依照事故致因理论,得出事故隐患三级原因,采用层次分析法对事故发生的频率和后果严重度及安全措施补偿系数的等级赋值,得到四级风险矩阵模型,对基本事件调查并由专家评估得出其风险值。评估结果表明导致实验室火灾事故的主要原因为:燃烧反应失控、加热、人员消防素质、操作不当、实验室管理水平、火灾报警系统缺陷、电气火花、灭火材料不足、消防系统缺陷、木制品、反应放热、存放不当。根据基本事件风险值高低针对性采取相应预防措施可以一定程度上提升实验室安全管理水平。     

Industrial accidents in spray dryer plants for dairy products in Europe

Despite the fact that the information about past accidents is an integral part of accident prevention, the information about industrial accidents is not commonly available in food and agricultural sectors. Spray dryer plants for dairy products are not an exception. The aim of this paper is the creation of the representative database for industrial spray drying accidents in order to identify their major causes. The paper is divided into 8 chapters. The first two chapters deal with the general information about technology of spray drying of dairy products. The third chapter provides the outputs from the authors' database containing records of 25 accidents in milk drying facilities in Europe. These accidents took place between 1999 and 2019 in six European countries. Based on the accident database, the most common causes of accidents were identified. Processes that can cause a fire, an explosion, or damage to environment are described in the fourth, fifth and sixth chapter. The seventh chapter deals with process, technical and organizational measures; these were discussed using literature research and the results of the accident database. The eighth chapter is the conclusion with a focus on further improvement of process safety through newly developed protective tools.     

一起炉窑空气管道泄爆膜爆破事故原因及措施

结合一起炉窑助燃空气管道泄爆膜爆破事故,通过现场勘查、询访、谈话等方式,对事故发生经过进行了调查,从设计、施工、安全管理等方面入手,对事故发生原因进行了分析,并从工程技术、管理、教育等方面有针对性地提出了避免类似事故发生的预防措施.