全球产品策略与其他化学品风险评估

为推动化学品风险评估在我国的开展,对全球产品策略(GPS)进行研究。通过对GPS实施流程的分析,确定实施GPS的核心是开展化学品的风险评估(简称GPS风险评估)。将GPS风险评估与欧盟《化学品注册、评估、授权和限制》(REACH)法规要求的化学品安全评估(简称REACH CSA)和我国新化学物质登记要求的新物质风险评估进行对比,从评估物质的要求、效应评估的范围和方法、暴露评估的范围和方法以及风险表征的方法 4个方面分析其共同点和差异。确定GPS风险评估是简化版的REACH CSA,新物质风险评估相当于REACH CSA中的环境风险评估部分。最后认为,开展化学品全面风险评估是国际化学品管理发展的趋势。针对实际情况,提出宜采取简化评估和优先评估的方法,在我国逐步开展化学品全面风险评估。     

一种基于层次分析法的危险化学品源安全评价综合模型

危险化学品源的安全评价是安全生产管理中的一项重要内容.目前用于危险化学品源安全评价与分级的常用方法有后果分析法、道指数法、蒙德指数法以及使用临界系数判别重大危险源的方法等.在实际应用中,单独使用某一方法时,由于存在各种片面性问题而得不到满意的评价结果; 几种方法同时使用时,其评价指标、评价结果以及结果的形式又会互相冲突.为解决上述问题,建立了基于层次分析法的综合评价模型.首先,根据安全评价要求构建3层次的评价体系,在各层次中构造判断矩阵,并计算4种常用方法相对综合评价模型的置信度; 其次,对各方法统一危险分级标准,均采用危险分数划定危险级别,并取各危险分数的加权平均值--综合危险分数作为综合评价模型下的危险源分级标准.采用综合评价模型可消除单一方法进行评价时的片面性和偏差,同时,评价结果的一致化使得判断危险化学品源的危险级别以及由此采取相应级别的管理措施成为可能,将更有利于实际安全生产管理指导.     

Modeling and application of risk assessment considering veto factors using fuzzy Petri nets

Risk assessment is important for plant safety, and fuzzy set theory is useful for such assessment because many risk factors have fuzzy characteristics. In this study, veto factors for risk assessment are taken into account. Weighted fuzzy Petri nets (WFPN) with inhibitor arcs are proposed to model relationships between risk factors and establish the risk assessment structure considering veto factors. Definitions of WFPNs as well as the enabling rule and execution rule are provided. The modeling approach for the assessment combining normal factors with veto items is discussed. The proposed fuzzy risk assessment approach is illustrated by an example of the assessment of production installations and process technology of plants that deal with hazardous chemicals. Veto factors and non-veto factors are presented and the assessment structure based on WFPNs is established. Using the factor data of a plant, an assessment value is obtained through the operation of WFPNs and the verification of the approach is discussed.     

Quantitative risk assessment model of hazardous chemicals leakage and application

The hazardous chemical accidents remain a matter of major concern. However, there is a dearth of practical measures about the emergency management of hazardous chemicals leakage. Therefore, in order to provide more accurate management plan, quantitative risk assessment has become a critical issue in chemical industry. The main aim of this study is to quantify the risk of hazardous chemicals leakage, and take precautions against the accidents. In this study, a Fire-Explosion-Poisoning Quantitative Probability Model (FEPQPM) has been established. The paper introduced the probability analysis methods to analyze derivative accidents caused by hazardous chemicals leakage, established quantitative risk assessment models, and made acceptable risk level analysis. This model has been applied to quantitatively assess an enterprise’s storage tank at Changshou Chemical Industrial Distripark (CID) in Chongqing, China. Evaluation results are in line with the actual situation of the CID. It is shown that the probability of poisoning is very large, causing more economic loss than the other two types of accidents, and death toll of leakage accident increases over time, resulting in greater economic losses. The risk level of leakage accident involving poisoning is unacceptable.     

健康风险暴露评价研究进展

综述了国内外健康风险暴露评价的最新研究进展,重点讨论了对人体进行直接监测的生物监测技术和对环境中污染因子进行间接监测并利用数学模型进行暴露剂量计算的间接方法。生物监测方法通过测定人体生理介质(如血液、尿液)中的污染物质及其代谢产物含量确定人体对环境污染物的暴露情况,监测结果反映了风险因子通过所有暴露途径进入人体的总暴露剂量。为了利用生物监测结果评价人体暴露安全性,近几年建立了生物监测等效值的概念,推导确定化学物质的生物监测等效值发展迅速。环境监测和数学模型间接方法通过对不同暴露媒介中风险因子的浓度监测和特定暴露途径的量化研究,同时利用精确的暴露计算模型(如空气分散模型、地下水扩散模型)计算人体对污染物的暴露剂量。生物监测和环境监测技术及数学模型的发展使健康风险评价和管理的暴露参数更加精确,降低了风险评价的不确定性。还介绍了利用数学模拟和剂量重建等方法插补历史空白暴露数据的方法。     

基于贝叶斯网络的危化品爆炸事故电力系统风险评估模型*

为提高危化品爆炸事故电力应急预警的准确性,建立基于贝叶斯网络的危化品爆炸事故电力系统风险评估模型。基于危化品爆炸事故电力应急典型情景分析,建立综合考虑突发事件、承灾载体和应急管理等风险因素的贝叶斯网络结构。应用概率刻画风险因素信息的不确定性及其相互影响,定量分析事件后果。结合一般条件和典型情景等的应用实例,分析评价方法和风险因素对风险等级的影响。结果表明:该模型能够在危化品爆炸事故发生后,评价电力应急预警等级;能够在危化品爆炸事故发生前,分析典型情景的风险和风险因素的影响,为应急准备提供支持;“最大概率法”较“概率加权求和法”得出的事件等级可能较低。     

低温乙烯储存过程风险评价及其缓解对策

为加强危险化学品储存的环境安全性,在深入调研危化品储存环节主要风险的基础上建立评价指标体系,采用层次分析法与模糊综合评价法相结合的风险评估模型对低温乙烯罐储存过程进行风险评估,并提出可行的控制措施。研究结果表明,储罐环境安全处于安全级内;针对低温乙烯罐存在的风险建立EHS一体化管理模式,建立全厂应急预案及一系列的风险预防措施,以缓解其储存过程的风险。     

化工园区泄漏事故安全风险评估模式研究

为减少化工事故频发造成严重人员伤亡及财产损失,在分析危化品泄漏事故类型的基础上,从事故发生概率和事故后果两方面提出危化品泄漏事故风险评估模型.以中毒事故为例,对重庆长寿化工园区内某企业一液氨储罐进行风险评估.基于概率模型计算中毒事故概率,结果表明该储罐发生泄漏引起中毒的概率较小;数值模拟结果显示:影响范围随时间的增加而...     

Terror-Proofing Chemical Process Industries

The chemical process industries (CPI) handling hazardous chemicals can be rather attractive targets for deliberate adversarial actions by terrorists, criminals and disgruntled employees. The damage inflicted may include casualties, economic loss and political fallout. There is an urgent need for each facility to have a security management programme. Its essential components are security risk assessment, security countermeasures and emergency response.

Security risk assessment can be carried out qualitatively by threat analysis, vulnerability analysis and developing a Security Risk Factor Table (SRFT). All these are discussed at length. Security countermeasures are the steps taken to strengthen the weak points in a system, either by lessening vulnerabilities or by hardening the facilities. Various security countermeasures are suggested for improving security of CPI. Appropriate emergency response measures that could mitigate the consequences of a successful attack are also discussed in the paper. It is recommended that many of the conventional safety and security measures adopted thus far may have to be modified in light of the enhanced and complex nature of the present security threats.     

Risk-relevant indices for the characterization of persistence of chemicals in a multimedia environment

The present research study proposes a new set of appropriately defined indices for the characterization of persistence of chemicals in a multimedia environment that prominently figures as a key exposure-based indicator within contemporary frameworks of chemical hazard and risk assessment, as well as recent international regulatory initiatives. Effectively overcoming some of the limitations associated with traditional approaches that could lead to a potential misclassification of chemical substances, the proposed set of persistence indices retain also a conceptually insightful and computational appeal. Conceptually inspired by certain measures/indices for the characteristic time found in classic dynamic systems theory, and technically relying on notions and methods from the theory of matrices, the new performance indices can be easily calculated on the basis of a dynamic multimedia environmental model and the aid of a software package such as MATLAB. In particular, an extension of the notion of equivalence width as a quantitative proxy of overall persistence is introduced, that captures the dynamic history of the chemical's environmental behavior, while remaining independent of the particular release pattern and discharge conditions (thus overcoming the standardization difficulties encountered when a large number of chemicals need to be first screened and classified in a tiered hazard assessment methodology). Furthermore, a second persistence index is introduced whose value can be analytically calculated through the solution of a simple Lyapunov matrix equation bearing some resemblance to certain measures of system resilience used in theoretical biology and ecology, yet inspired by system-theoretic notions associated with the Lyapunov framework of analysis in systems science. Furthermore, for both persistence measures a comparison is made with the slowest time-constant associated with the specific chemical dynamics in a multimedia environment, and upper and lower bounds are established. Finally, the proposed persistence indices are calculated on the basis of a standard dynamic multimedia environmental model for various representative cases involving chemicals of particular interest.     

化工储罐区空袭次生灾害危险性评价研究

根据化工储罐区及其遭空袭次生灾害的特点,以空袭次生灾害的影响范围作为危险性评价的标准,对化工储罐区的空袭次生灾害进行危险性评价。指出储罐遭空袭后的3种毁伤方式;给出储罐遭空袭发生的次生灾害及其扩散的形式与后果;阐述了化工储罐区空袭次生灾害的成灾机理;分别提出热辐射伤害、冲击波伤害和有毒有害物质扩散的危险性评价方法。以池火灾为例,建立了池火灾的危险性评价模型;论述了池火灾危险性评价的具体流程,并进行了案例分析,根据计算结果提出了相应的减灾对策。笔者认为,化工储罐区遭空袭后的次生灾害的危险性评价具有现实意义,对于化工园区、石化厂、危化品仓库等突发安全事故产生次生灾害的危险性评价同样具有重要的参考价值。     

危险化学品企业实施安全评价工作绩效分析

2006年安全生产工作取得了较好的成绩,呈现总体稳定趋向好转的发展态势,事故死亡人数总量也较大幅度下降。但是,在危险化学品行业非但没有得到扭转,事故死亡人数反而上升了16.2%。对此,我们有必要加强对危险化学品的安全管理。在安全评价方面,危险化学品企业实施安全评价后是否对企业的发展有实际的绩效,对此,我们对全国320家实施过安全评价的危险化学品企业进行了调研分析,尤其在安全设施、安全管理水平、事故发生频率等方面,并从中得出结论,进而了解评价过程中存在的不足,以及提出合理的对策措施。     

Qualitative risk assessment of a Dual Fuel (LNG-Diesel) system for heavy-duty trucks

A Dual Fuel (LNG-Diesel) system can be applied to heavy-duty diesel trucks for achieving environmental benefits in comparison to existing diesel vehicles. Because of lack of reports about risk assessment of this technology, we performed a qualitative assessment based on a framework of some literature techniques for risk identification, analysis and evaluation. After constructing a Reliability Block Diagram (RBD) to establish the context, we conducted bow-tie analysis, Fault Tree Analysis (FTA), Failure Mode and Effects Analysis (FMEA), likelihood and consequence analysis, and used a risk matrix. We applied these methods and techniques qualitatively to identify causes (e.g. collisions), critical events (e.g. releases of natural gas), related consequences (e.g. fires and explosions), and different possible pathways from a specific cause to its consequence, and to assess some negative accident scenarios related to use and parking of the vehicle. The bow-tie analysis also allowed to make explicit barriers and controls that prevent critical events and/or mitigate consequences. Therefore, we identified a set of safety measures, including design, technical, management, and emergency actions, which shall be implemented in each step of the system's life cycle.Our risk assessment showed that the risk level of the Dual Fuel (LNG-Diesel) system is similar to the risk level of a traditional diesel system. Future research will overcome current lack of data and, therefore, permit a quantitative rating of the risk of the Dual Fuel (LNG-Diesel) system.     

基于本质安全的化工工艺物质危险指数研究

建立了基于本质安全的化工工艺物质危险性的评价体系,包括火灾危险性、爆炸危险性以及毒性等3个评价指数.基于风险的思想,各个评价指数均包括概率指标与后果指标.为了全面反映化工工艺的实际情况,在各个评价指数中均对所有物质的相应指数值加和.参数的取值以以往的指数法为基础,为了消除边界波动效应,取值采用内插法.由于各个指数的量纲...     

基于危险化学品储存的区域生态环境风险评价

借鉴现有的生态风险评价方法,提出适合危险化学品储存的区域生态风险评价体系,即区域生态风险受体确定,评价终点选择,暴露途径和方式,暴露剂量分析与计算,风险表征以及区域生态风险管理对策等。研究结果表明:在有风模式中,鸟类的不可接受风险范围最远可达下风向7km,蛙类的不可接受风险最远可达下风向27km。大部分敏感点的蛙类急性暴露剂量都超标,处于不可接受风险水平;80%的敏感点的鸟类处于不可接受风险水平。根据风险评价结果,提出从防范措施、应急预案、环境监测和生态补偿4个方面制定区域生态风险管理措施。该区域生态环境风险评价研究为同类型区域生态环境风险评价提供借鉴作用。     

危险化学品泄漏事故点火概率取值研究

为计算危险化学品泄漏后发生火灾、爆炸等事故的概率,提高风险评估的量化水平,对点火概率的取值进行研究。从模型计算和直接取参考值2个方面探讨点火概率的取值问题,提出不同情形下的取值建议,并结合案例应用对点火概率2种取值方法进行对比分析研究。研究结果表明:点火概率模型计算不确定性较大且适用性有限,而直接取值的参考值均由一系列事件统计而得出,具有一定的科学性,实际取值更倾向于根据经验数据或已有的数据进行取值,但取值时需要充分考虑实际情况(如安全条件等)进行适当的修正,以便取值更科学。     

基于可拓层次分析法的东北林区贮木场火险等级评价研究

以贮木场火险等级评价为背景,基于贮木场火险因子的层次结构,采用可拓层次分析方法,建立东北林区贮木场安全评估指标体系。运用可拓层次分析法从不同层次上对贮木场进行火灾安全等级评价,客观的给出了较为有效的可拓区间数,确定了各个火险评级指标在东北林区的贮木场火险等级评价中的权系数。通过实例分析说明了可拓层次分析法在东北林区贮木场火险等级评价中的可行性,同时评价模型对构建贮木场火险等级的动态评估演化模型具有指导作用,为企业提高经济效益、实现科学管理提供一定的理论依据。     

危险化学品道路运输安全管理现状及发展趋势研究

为降低危化品运输风险,从危化品运输风险评价、道路选线模型、技术应用、应急联动机制及平台建设、统一联控监管平台等方面进行研究分析。通过对微观视角与宏观视角、单一应用与综合应用的归类和对比,进行分析并指出存在的问题。分析表明,获取精确连续数据,考虑多种外在变量来完善评估模型,注重理论、技术和监管资源的综合应用,发展大区域联控平台将是今后研究的发展趋势。     

Operational risk assessment: A case of the Bhopal disaster

Accidental releases of hazardous chemicals from process facilities can cause catastrophic consequences. The Bhopal disaster resulting from a combination of inherently unsafe designs and poorly managed operations is a well-known case. Effective risk modeling approaches that provide early warnings are helpful to prevent and control such rare but catastrophic events. Probability estimation of these events is a constant challenge due to the scarcity of directly relevant data. Therefore, precursor-based methods that adopt the Bayesian theorem to update prior judgments on event probabilities using empirical data have been proposed. The updated probabilities are then integrated with consequences of varying severity to produce the risk profile.This paper proposes an operational risk assessment framework, in which a precursor-based Bayesian network approach is used for probability estimation, and loss functions are applied for consequence assessment. The estimated risk profile can be updated continuously given real-time operational data. As process facilities operate, this method integrates a failure-updating mechanism with potential consequences to generate a real-time operational risk profile. The real time risk profile is valuable in activating accident prevention and control strategies. The approach is applied to the Bhopal accident to demonstrate its applicability and effectiveness.     

北京市危险化学品企业安全生产风险评估分级研究

为对北京市危化品企业基本情况的全面掌握,开展了危险化学品企业安全生产风险评估分级研究,借鉴国外经验和国内有关科研成果,提出了固有风险和动态风险相结合的危化品安全生产风险评估方法。固有风险为企业的基本风险水平,主要由危险化学品物质量、工艺水平、安全监控和周边环境决定,为共性指标;动态风险,反映企业安全生产管理绩效的水平,主要包括安全基础管理和现场管理,为个性指标,不同企业类型,评估动态风险指标有差异。从大量数据中抽取了最能反应企业安全生产状态的指标因素,通过专家组打分法和层次分析法确定评价因素的权重,该评估方法具有较强的实用性和可操作性,是本质安全和安全绩效的创新结合,为企业安全生产评估分级提供了新思路。通过分级,按照"风险优先"原则,政府部门实行差别监管,降低安全监管成本,促进危险化学品安全生产工作向规范化、科学化转变。同时,研制了危化品企业安全生产风险分级系统,为建立北京市危化品企业风险分级数据库奠定了基础。