《SIL级别介绍.pdf》由会员分享,可在线阅读,更多相关《SIL级别介绍.pdf(27页珍藏版)》请在三一文库上搜索。
1、IEC 61511 Safety Instrumented Systems Overview & Current Status Simon Brown BSc CEng MIEE HM Principal Specialist Inspector Control & Instrumentation Systems Health & Safety Executive 13/11/2002 IEC 61511 Background Overview Significant aspects (cf. IEC 61508) Selection of components / subsystems Mi
2、nimum hardware fault tolerance Software SIL determination Current status & way forward Background IEC 61508 Functional safety of E/E/PE safety-related systems Generic IEC Basic Safety Publication HSE benchmark, subject to sector standards or industry standards / guidelines ANSI / ISA S.84.01 Applica
3、tion of Safety Instrumented Systems for the Process Industries US National standard OSHA recognised under 29 CFR (Process Safety Management of Highly Hazardous Chemicals etc.) (1910.119) IEC 61511 likely to supersede IEC SC65A / WG10 / TG C Chair Vic Maggioli (ex Dupont) Dupont, Shell, Dow, BASF, El
4、f, BNFL, EDF ABB, Honeywell, Triconex, Siemens, ICS, Yokogawa, Toshiba, Kongsberg Simrad Emerson Process, Silvertech Blacksafe, Virkonnen, SIS-Tech, FM HSE Overview IEC 61511 Functional safety Safety instrumented systems for the process industry sector IEC 61511-1 Framework, definitions, system, har
5、dware and software requirements IEC 61511-2 Guidelines on the application of IEC 61511-1 IEC 61511-3 Guidance for the determination of the required safety integrity levels Scope Process (chemicals, oil & gas, paper, non- nuclear power generation) End-to-end safety instrumented system (SIS) - h/w, s/
6、w, mgt. and human factors Full safety lifecycle - specification, design, integration, operation, maintenance Intended for integrators / users not for equipment designers / vendors Principles (1) Safety instrumented functions & SILs determined from hazard & risk analysis Safety requirements specifica
7、tion Reliability modelling System behaviour on detection of fault Minimum hardware fault tolerance Application software development Principles (2) Management of functional safety Safety lifecycle model Competency Functional safety assessment Independence Planning Configuration management Verificatio
8、n & validation Failure model Basic Process Control System d 10-5/hrDemands SIL Safety Instrumented SystemPFDavg Hazards h= d . PFDavg SILs Target PFD (demand mode) or dangerous failure rate (continuous mode) set by: process risk tolerable risk target other means of protection SIL defined according t
9、o PFD / failure rate SILs Probability of failure of safety instrumented function 10-6to 10-5 10-2to 10-11 10-7to 10-6 10-3to 10-22 10-8to 10-7 10-4to 10-33 10-9to 10-8 10-5to 10-44 Continuous mode (prob. of a dangerous failure in an hour) Demand mode (prob. of a dangerous failure on demand) SIL Sign
10、ificant Aspects (1) Selection of components & subsystems Selection of components & subsystems SIL 1 to SIL 3: to IEC 61508 or to IEC 61511 requirements for selection based on prior use and minimum hardware fault tolerance SIL 4: to IEC 61508 Selection of components and subsystems based on prior use
11、(1) Classified according to type of software used FPL, LVL, FVL All types - evidence of suitability required vendor quality / specification / previous use Fixed Program Language (e.g. smarts) evidence of suitability based on specific configuration of hardware & software, SIL 3: formal assessment & s
12、afety manual Selection of components and subsystems based on prior use (2) Limited Variability Language (eg PLC) Assessment of differences in operational profiles & physical environments Operating experience based on SIL Safety configured general purpose PLCs allowed at SIL 1 and SIL 2 provided that
13、: understanding of failure modes and techniques to address identified failure modes formal assessment against specified criteria required at SIL2 Full Variability Language - to IEC 61508 Significant Aspects (2) Minimum hardware fault tolerance Minimum hardware fault tolerance Logic solvers as IEC 61
14、508 Sensors & final elements: If dominant failure mode to safe state or faults detected, otherwise increase by 1 reduce by 1 if: proven, fixed logic, SIL4 IEC 615084 23 12 01 Fault toleranceSIL Equivalent to IEC 61508-2 Table 3 SFF = 60-90% Type B Significant Aspects (3) Software Software Applicatio
15、n S/W Up to SIL 3 FPL or LVL Embedded software to meet requirements for selection of components & subsystems Utility software Support tools, user manual, application languages Specific requirements No SIL grading Safety manual SIL 4 - IEC 61508 Significant Aspects (4) SIL Determination Process risk
16、(Consequence, frequency) Tolerable risk Other risk reduction measures Required risk Reduction (PFD) Or Tolerable failure rate SIL SIL determination QRA Safety Layer Matrix Calibrated risk graph (methodology only not definitive) Qualitative risk graph Layer of protection analysis (LOPA) Current Statu
17、s & Way Forward IEC 61511 Functional safety: Safety instrumented systems for the process industry sector IEC 61511-1 General requirements IEC 61511 2 Guidance IEC 61511-3 Guidance for the determination of the required safety integrity levels IEC 61511-1 Final vote due 29-11-02 IEC 61511-2 Final draft in preparation IEC 61511-3 Final vote due 15-11-02 Publication anticipated early 2003
链接地址:https://www.31doc.com/p-3678905.html