模糊综合评价在实验室安全管理评价中的应用

由于高校和科研部门中的实验室安全隐患多、运行管理复杂,故对应的安全管理评价指标和方法难以确定。模糊综合评价方法是解决影响因素多、评价指标复杂问题的常用方法。通过总结和研究高校实验室安全管理的特点,对多个实验室进行实地考察,并在听取专家意见的基础上,建立实验室安全管理评价指标体系,结合层次分析法确定了各指标的权重。通过专家打分得到综合评价矩阵,采用基于加权平均算子的模糊数学方法得到实验室安全管理评价的结果集。将该方法应用于某实验室的安全管理评价,分析得出安全管理中的薄弱环节,为采取有效的风险预控措施提供了一定的理论依据。     

基于改进相互作用矩阵的基坑施工安全风险评价

为解决现有基坑施工风险评价方法过于单一、客观性不足的问题，从勘察设计与监测、支护结构、土方施工、排水与降水、周围环境5个方面选取19个基坑施工安全影响因素；利用引入C-OWA算子的相互作用矩阵对其进行交互耦合分析，考虑各因素的单独作用效果的同时，在削弱专家主观偏好和综合考虑各因素相关性的基础上，研究其协同作用效果；最后用实例验证方法的实用性，结果表明:该项目整体风险偏高，其中排水系统能力、地下水水位和地下管线埋布是影响该基坑施工安全的主要风险因素，需重点防控。     

综合安全评价(FSA)方法

为提高国际海运安全管理的决策水平,国际海事组织(IMO)接受并倡导由英国海运界提出的综合安全评价(FSA)方法,笔者对FSA方法作了本质性分析和应用性研究。阐述了FSA的由来,5个组成步骤及相互关系和流程,揭示了FSA与风险管理和安全系统工程的渊源;介绍了危险识别的7种工具;对步骤二“风险评估”重点引入了半定量分析方法和定量分析方法,并用集合论观点讨论了事故频率和后果严重度的计算方法;介绍了风险控制方案的“成本与效益评估”的数学模型;归纳了FSA方法的优缺点。指出FSA是一种集风险评价和成本/效益评估于一体,兼顾技术性与经济性,可广泛兼容具体评价方法和普遍适用各类风险评价的框架性方法,但具体应用需要有效整合适用的定性和定量方法。     

节段预制悬臂拼装梁施工安全风险评价

为了准确地对节段预制悬臂拼装梁的施工过程进行安全风险评价，对该类桥梁的施工提供有效借鉴，提出基于组合赋权的灰色聚类综合评价模型。首先根据该施工技术的工艺特点及相关规范，建立风险评价指标体系，利用G1法和C-OWA算子分别确定评价指标体系的主观权重和客观权重，并运用最小信息熵原理优化组合赋权，进一步利用三角白化权函数建立灰色聚类评价模型，确定风险综合评价值，最后依据风险测度界定范围判断施工安全风险等级。最后，运用此评价模型进行实例分析，并根据评价结果提出改进策略，同时验证了该模型的适用性和有效性，进而为该类桥梁施工安全风险管控策略的制定提供理论依据。     

Risk assessment of safety level in university laboratories using questionnaire and Bayesian network

Accidents in university laboratories not only create a great threat to students’ safety but bring significant negative social impact. This paper investigates the university laboratory safety in China using questionnaire and Bayesian network (BN) analysis. Sixteen influencing factors for building the Bayesian net were firstly identified. A questionnaire was distributed to graduate students at 60 universities in China to acquire the probability of safe/unsafe conditions for sixteen influencing factors, based on which the conditional probability of four key factors (human, equipment and material, environment, and management) was calculated using the fuzzy triangular theory and expert judgment. The determined conditional probability was used to develop a Bayesian network model for the risk analysis of university laboratory safety and identification of the main reasons behind the accidents. Questionnaire results showed that management problems are prominent due to insufficient safety education training and weak management level of management personnel. The calculated unsafe state probability was found to be 65.2%. In the BN analysis, the human factor was found to play the most important role, followed by equipment and material factor. Sensitive and inferential analysis showed that the most sensitive factors are personnel incorrect operation, illegal operation, and experiment equipment failure. Based on the analysis, countermeasures were proposed to improve the safe management and operation of university laboratories.     

一种新型危险化工工艺安全评估方法的设计

在安全生产过程中,建设项目风险评价在我国经过几十年的发展,无论在模型亦是方法上均有所进步,但对化工项目进行危险化工工艺风险等级评价的研究并不多见。本文按照危险化工工艺表征涉及的影响因素,在参考了日本劳动省"六阶段"的定量评价表以及危险度评价法并对15种危险化工工艺定性分析的基础上,提出了一种基于危险度评价法的更为全面的危险化工工艺辨识方法。该评价方法可用于确定危险化工工艺的风险等级。为化工企业工艺危险的实时评估和安全管理提供技术支撑和科学途径。     

Bayesian networks based laboratory retrofitting towards inherent safety: A risk-based implementation framework

Over the years, a number of high-profile laboratory accidents involving severe injuries, fatalities, and economic losses have been reported, prompting a significant increase in efforts towards laboratory safety. However, the dominant safety measures rely excessively on add-on safeguards such as sprinklers and respirators and pay little attention to reducing the hazardous factors at their sources. This study introduced the inherent safety concept to minimize laboratory hazards and developed a dedicated implementation tool called Generic Laboratory Safety Metric (GLSM). The Traditional Laboratory Safety Checklist (TLSC) was first used to represent the safety indicators, and then the Precedence Chart (PC) and Bayesian Networks (BN) methods were used to reconcile the safety indicators to develop the GLSM. The developed GLSM was subsequently demonstrated through a case study of a university laboratory. The results revealed that the safety level increased from 2.44 to 3.52 after the risk-based inherently safer retrofitting, thus creating laboratory conditions with a relatively satisfactory safety level. This work presented a set of generic solutions to laboratory retrofitting towards inherent safety with a novel GLSM as the implementation tool. The proposed GLSM would contribute to risk quantification and identification of key risk factors for assigning targeted and fundamental safety measures to achieve inherently safer laboratories.     

At-risk behaviour analysis and improvement study in an academic laboratory

Academic laboratories contain inherently substantial risk conditions that students could expose to chemical and physical hazards. Procedures and guidelines related to laboratory safety are commonly available for students to adhere. However, many injuries and accidents or even fatalities are reported due to students’ violated safety practices while working in the laboratory. There was no reported proactive method or systematic technique to monitor and control students’ at-risk behaviour in the laboratory. This paper presented a program known as laboratory at-risk behaviour and improvement system (Lab-ARBAIS) to monitor and control students’ at-risk behaviours in the laboratory. Lab-ARBAIS used computer database for data acquisition and analysis on students’ at-risk behaviours observed. Pre-program questions on students’ at-risk behaviours that frequently violated safety regulations were utilized by observers to give observation feedback. The collected feedback was analysed and the results were posted in students’ portal to allow everyone to acknowledge their safety habits and practices. The routine observations and posted results are to instill a psychology effect in student’s habitual safety practices by reminding them on their frequently violated safety regulations. The implementation of the Lab-ARBAIS program to chemical engineering laboratory as a case study had shown a significant improvement on students’ frequent at-risk behaviours. The Lab-ARBAIS can easily be adopted in any academic laboratories to manage students’ at-risk behaviours to ensure safe work environment. With minor enhancement, the Lab-ARBAIS can easily be extended to be used in industrial laboratories.     

Aspects of risk analysis associated with major failures of fuel pipelines

This paper presents a methodology of risk assessment for hazards associated with transportation of dangerous substances in long pipelines. The proposed methodology comprises a sequence of analyses and calculations used to determine basic reasons of pipeline failures and their probable consequences, taking individual and societal risk into account. A specific feature of this methodology is a combination of qualitative (historical data analysis, conformance test and scoring system of hazard assessment) and quantitative techniques of pipeline safety assessment. This enables a detailed analysis of risk associated with selected hazard sources by means of quantitative techniques. On the ground of this methodology typical problems that usually pose serious threat and constitute part of risk analysis for long fuel pipelines are also presented. To verify above methodology, complete risk analysis was performed for the long distance fuel pipeline in Poland.     

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.     

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...     

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.     

Risk-based maintenance (RBM): a quantitative approach for maintenance/inspection scheduling and planning

The overall objective of the maintenance process is to increase the profitability of the operation and optimize the total life cycle cost without compromising safety or environmental issues. Risk assessment integrates reliability with safety and environmental issues and therefore can be used as a decision tool for preventive maintenance planning. Maintenance planning based on risk analysis minimizes the probability of system failure and its consequences (related to safety, economic, and environment). It helps management in making correct decisions concerning investment in maintenance or related field. This will, in turn, result in better asset and capital utilization.

This paper presents a new methodology for risk-based maintenance. The proposed methodology is comprehensive and quantitative. It comprises three main modules: risk estimation module, risk evaluation module, and maintenance planning module. Details of the three modules are given. A case study, which exemplifies the use of methodology to a heating, ventilation and air-conditioning (HVAC) system, is also discussed.     

基于LOPA逻辑的罐区多米诺效应定量风险评估*

为了更好地降低化工企业罐区事故造成多米诺效应的风险,提出1种基于保护层分析（LOPA）的定量风险评估程序。首先,阐述基于保护层分析(LOPA)逻辑的多米诺定量风险评估流程,即引入包括可用性、有效性及3种逻辑门定义及量化的安全屏障定量评估;然后,利用LOPA的分析逻辑将安全屏障融入多米诺定量风险评估框架中;最后,选取2×2 000 m3苯乙烯罐区为对象,识别防火层与喷淋冷却系统2种安全屏障并开展基于LOPA逻辑的罐区多米诺效应定量风险评估,得出安全屏障能有效地降低多米诺事故发生频率及罐区个人风险的结论。研究结果表明:该分析方法可为化工企业开展多米诺效应定量风险评估提供参考。     

Embedding the human factor in road tunnel risk analysis

The paper is focusing on road tunnel safety and builds upon the Directive 2004/54/EC launched by the European Commission; the latter sets basic requirements and suggests the implementation of risk assessment in several tunnel cases apart from technical measures imposed on the basis of tunnel structural and operational characteristics. Since the EU Directive does not indicate the method for performing risk assessment, a wide range of methods have been proposed, most of them based on quantitative risk assessment (QRA). Although the majority of current road tunnel QRAs assess physical aspects of the tunnel system and consider several hazards concerning the transportation of dangerous goods through a tunnel, they do not take into account, sufficiently, several organizational and human-related factors that can greatly affect the overall safety level of these critical infrastructures. To cope with this limitation this paper proposes a fuzzy logic system based on CREAM method for human reliability analysis (Hollnagel, 1998) in order to provide more sophisticated estimations of the tunnel operator's performance in safety critical situations. It is deduced that a human reliability analysis component to analyze operator performance, like the fuzzy system proposed here, is important for risk analysts. Consideration of organizational and human factors will enhance risk analysts’ studies and highlight the uncertainty related to human performance variability.     

Dynamic-risk-informed safety barrier management: An application to cost-effective barrier optimization based on data from multiple sources

An integrated approach for performance assessment and management of safety barriers in a systemic manner is needed concerning the prevention and mitigation of major accidents in chemical process industries. Particularly, the effects of safety barriers on system risk reduction should be assessed in a dynamic manner to support the decision-making on safety barrier establishments and improvements. A simulation approach, named Simulink-based Safety Barrier Modeling (SSBM), is proposed in this paper to conduct dynamic risk assessment of chemical facilities with the consideration of the degradation of safety barriers. The main functional features of the SSBM include i) the basic model structures of SSBM can be determined based on bow-tie diagrams, ii) multiple data (periodic proof test data, continuous condition-monitoring data, and accident precursor data) may be combined to update barrier failure probabilities and initiating event probabilities, iii) SSBM is able to handle uncertainty propagation in probabilistic risk assessment by using Monte Carlo simulations, and iv) cost-effectiveness analysis (CEA) and optimization algorithms are integrated to support the decision-making on safety barrier establishments and improvements. An illustrative case study is demonstrated to show the procedures of applying the SSBM on dynamic risk-informed safety barrier management and validate the feasibility of implementing the SSBM for cost-effective safety barrier optimization.     

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。     

在役化工装置安全评价指标体系构建方法的探讨

分析当前在役化工装置安全评价指标体系建立中存在的问题,提出"从风险分析到措施"的建立安全现状评价指标体系的新思路。探讨综合应用事故树分析法、层次分析法等方法并建立安全评价指标体系及确定指标权重的具体方法,使评价指标的建立及指标权重的确定更具有科学性。通过具体的化工装置安全评价指标建立及其权重确定的过程,介绍该方法的具体应用,不仅适用于在役化工装置的安全评价,也适用于其他系统的安全现状评价。该评价指标体系既能查找出装置中存在的具体安全隐患,也能给出装置总体安全性评价结论。     

化工过程本质安全性之模糊评价系统

在综合分析化工过程构成的基础上,建立的化工过程本质安全性评价指标,借鉴国内外本质安全评价的研究,应用Matlab模糊推理系统,以评价指标的等级划分、隶属度函数设计及推理规则设定等为主线,建立化工过程本质安全性模糊评价系统,实现评价指标和评价推理结果的可视化。通过甲苯高温加氢脱烷烃制取苯的工艺过程,实施不同工艺路线及其操作条件改变的本质安全性评价,验证了所建立模糊评价系统的可行性。研究结果对指导化工安全设计和安全评价、减少和消除重大危险源,进一步提升我国化工行业的整体安全水平具有重要的理论和现实意义。