1、Safety Engineering,NASAs illustration showing high impact risk areas for the International Space Station,Safety engineering is an engineering discipline which assures that engineered systems provide acceptable levels of safety. It is strongly related to industrial engineering/systems engineering, an
2、d the subset system safety engineering. Safety engineering assures that a life-critical system behaves as needed, even when components fail.,常用术语,危险：hazard 安全：safe 事故：accident 风险：risk 灾害：disaster 系统：system 可靠性：reliability 安全分析：safety analysis 安全评价：safety evaluation,Accident causation models 事故致因理论 S
3、afety management 安全管理 Physical conditions 物质条件 Loss prevention 损失预防 Top management高层管理人员 Human errors人因失误 Hazard control 危险控制 Corporate culture 企业文化 Risking taking 冒险行为,Safety officer 安全官员 Safety committee 安全委员会 Unionized company 集团公司 Safety principle 安全规则 Status review 状态审查 Supervisory level 监督层 Im
4、plement plan 执行计划 Hazard identification 危险辨识 Safety performance 安全性能,Systems engineering is an interdisciplinary field of engineering and engineering management that focuses on how to design and manage complex systems over their life cycles. At its core systems engineering utilizes systems thinking
5、principles to organize this body of knowledge. Issues such as requirements engineering, reliability, logistics, coordination of different teams, testing and evaluation, maintainability and many other disciplines necessary for successful system development, design, implementation, and ultimate decomm
6、ission become more difficult when dealing with large or complex projects.,System Engineering,Systems engineering deals with work-processes, optimization methods, and risk management tools in such projects. It overlaps technical and human-centered disciplines such as industrial engineering, mechanica
7、l engineering, manufacturing engineering, control engineering, software engineering, electrical engineering, cybernetics, organizational studies and project management. Systems engineering ensures that all likely aspects of a project or system are considered, and integrated into a whole.,The systems
8、 engineering process is a discovery process that is quite unlike a manufacturing process. A manufacturing process is focused on repetitive activities that achieve high quality outputs with minimum cost and time. The systems engineering process must begin by discovering the real problems that need to
9、 be resolved, and identify the most probable or highest impact failures that can occur systems engineering involves finding elegant solutions to these problems.,System characteristics: Unity整体性 Relativity相关性 Objective, Goal & Function目的性和功能性 Adaptability to the Environment环境适应性 Dynamic动态性 System has
10、 its own order有序性,Classification of system,Natural and Human-Made System 自然系统和人工系统 Physical and Conceptual System 实体系统和抽象系统 Static and Dynamic System 静态系统和动态系统 Control and Behavior System 控制系统和行为系统 Open and Closed System 开放系统和封闭系统,System engineering method,Engineering logic Engineering analysis Stat
11、istical theory and probability theory Operations research,System engineering principle,系统原理 整分合原理 反馈原理 弹性原理 封闭原理 能级原理 动力原理 激励原理,System principle Principle of integral -division Feedback principle Elasticity principle Closure principle Energy level principle Dynamic principle Incentive principle,Safe
12、ty System Engineering,1.Features of safety system 系统性 开放性 确定性与非确定性 有序与无序的统一体 突变性或畸变性,Systematicness Openness Certainty and uncertainty Unity of order and disorder Sudden or abnormal degeneration,2.Safety System Engineering Definition,安全系统工程是运用系统工程方法，识别、分析、评价系统寿命周期中的危险性，根据其结果调整工艺、设备、操作、管理、生产周期和投资等因素，
13、控制可能发生的事故，使系统处于最佳安全状态。,Definition,Safety system engineering is a method of using system engineering to identify, analyze and evaluate the hazards in the life cycle of a system. According to the results, it adjusts the process, equipment, operation, management, production cycle, investment and other
14、factors to control the possible accidents, so that the system is in the optimal security state.,Three subsystems: Human subsystems Machine subsystems Environment subsystem,3.Research object of safety system engineering,These three interrelated, mutually constrained, interactive subsystems constitute
15、 an organic whole of a “human-machine-environment“ system. Analysis, evaluation, control “human - machine - environment“ system security, can really solve the system safety issues.,4.Research contents of safety system engineering,The basic task of safety systems engineering is to predict, evaluate a
16、nd control hazards. The analysis process can be summarized as follows: System safety analysis (identification and forecasting hazards); Risk (safety) evaluation (including human, machine, material, craft, environment, organization, etc); Comparison; Comprehensive evaluation; Optimize the decision of
17、 the plan. The main technical means can be summarized as system safety analysis, system safety evaluation and safety decision-making and accident control., System Safety Analysis,Through the system safety analysis, you can identify the dangerous sources in the system, analyze the possible dangerous
18、states, estimate the probability of the accident, the possible damage and the severity of the consequences, by modifying the system design or change the control system to run the program.,main content,Investigate and analyze the various dangerous sources and their relations in the system Conduct inv
19、estigation and analysis of system-related environmental conditions, equipment, personnel and other relevant factors Analyze measures that can take advantage of appropriate equipment, procedures, processes or materials, control or eradicate a particular hazard source Investigating and analyzing hazar
20、d control measures and the best way to implement these measures Investigation and analysis of dangerous sources that can not be eradicated to lose or reduce the possible consequences of control Investigation and analysis of safety hazards in order to prevent injury and loss if the hazard is out of c
21、ontrol,Common method,预先危险性分析 （PHA） 安全检查表分析（SCA） 故障模式及影响分析 （FEMA） 危险和可操作性研究(HAZOP) 事件树分析(ETA) 事故树分析（FTA) 系统可靠性分析（） 原因-后果分析（CCA),Preliminary Hazard Analysis Safety Checklist Analysis Failure Mode and Effect Analysis Hazard and Operability Analysis Event Tree Analysis Fault Tree Analysis System Reliabi
22、lity Analysis Cause Censequence analysis,Classification,Induction,Qualitative analysis,Quantitative analysis,Deduction,Preliminary Hazard Analysis(PHA)，是在每项工作活动之前，对系统存在的危险类型、来源、出现条件、到事故后果及相关措施，作一概略分析。总之，即在行动之前作一安全分析，以避免考虑不周造成的各种损失。,1、Main content of PHA,识别危险的设备、零部件并分析其发生的可能性和条件； Identify dangerous e
23、quipment, parts and analyze the likelihood and conditions of their occurrence; 分析系统中各子系统，各元件的交接面及其相互关系与影响； Analysis of the subsystems in the system, the components of the intersection and their relationship ,分析物质危险性（MSDS，相关的检测）； Analysis of material hazards 分析工艺过程危险性(含装置存在的危险性) ； Analyze the process
24、 hazard (including the presence of the device) 人、机关系(操作、维修等) Human-machine relationship 环境条件危险性分析； Risk analysis of environmental conditions 防护措施和安全保障分析。 Protection measures and safety and security analysis.,2、advantages,分析工作在行动之前，可以及早排除、降低和控制危险； Early elimination, reduction and control of hazards;
25、系统开发、设计、制造、安装、检修等过程的分析结果，可以作为应遵循的注意事项和指导方针； Guidelines 可为制定标准和规范提供必要资料； 可以作为安全教育的教材。 Safety education,General steps Preliminary Hazard Analysis including three stages: preparation, review, and the results summary,确定系统对象； 资料调查收集； 系统功能分解； 分析辨识危险； 确定危险等级； 制定措施； 实施措施。,Determine the system object; Data c
26、ollection; System function decomposition; Analysis and identification of hazards; Determine the hazard level; Develop measures; Implementing measures.,分析、辩识危险 Dangerous and harmful factors,Inherent risk,Occupational disease,Risk of storage,1、Safety Analysis of Household Water Heater,热水器用煤气加热，装有温度和煤气
27、开关连锁，当水温超过规定温度时，连锁动作将煤气阀门关小；如果发生故障，则由泄压安全阀放出热水，防止事故发生。为了防止煤气漏出和炉膛内滞留煤气在热水器内设有燃气安全控制系统，由长明火、热电偶和电磁阀组成。由于长明火存在，即使溢出煤气也不会发生爆炸。若长明火灭了，热电偶起作用，通过电磁阀将煤气关闭，防止事故发生。,Water heater heating by coalgas. It equipped with temperature and gas switch chain, when the water temperature exceeds the specified temperature
28、, the chain action will close the gas valve; If the fault occurs, accidents prevented by the hot water release from pressure relief valve. In order to prevent gas leakage and furnace gas retention, the gas safety control system is located outside the heater. In order to prevent gas leakage and furna
29、ce gas retention. Gas safety control system consists of everlasting fire, thermocouple and electromagnetic valve. Due to the existence of everlasting fire, explosion will never happen even if the gas leak . If the fire is off, the thermocouple work and turn off gas by electromagnetic valve for preve
30、nting accidents.,Fault Tree Analysis,Fault tree analysis (FTA) is a top down, deductive failure analysis in which an undesired state of a system is analyzed using Boolean logic to combine a series of lower-level events.,Fault Tree Analysis,This analysis method is mainly used in the fields of safety
31、engineering and reliability engineering to understand how systems can fail, to identify the best ways to reduce risk or to determine (or get a feeling for) event rates of a safety accident or a particular system level (functional) failure.,Fault Tree Analysis,The basic symbols used in FTA are groupe
32、d as events, gates, and transfer symbols.,Failure mode and effects analysis,Failure mode and effects analysis (FMEA)also “failure modes“, plural, in many publicationswas one of the first highly structured, systematic techniques for failure analysis.,Risk is the combination of End Effect Probability And Severity,
