IEC 61511-3:2003 Functional safety – Safety instrumented systems for the process industry sector – Part 3: Guidance for the determination of the required safety integrity levels (Edition 1.0; Incorporates Corrigendum 1: 10/2004)
This section provides information related to the following:
——basic concepts of risk and the relationship between risk and safety integrity, see Chapter 3;
——determination of allowable risks, see Appendix A;
——determination of the safety integrity of instrument safety functions See Appendix B, Appendix C, Appendix D, Appendix E, and Appendix F for various methods of sexual rating. In particular: a) This standard may be used when one or more instrumented safety functions are used to achieve functional safety in order to protect people, public facilities or the environment; b) This standard may also be used in non-safety applications such as asset protection; c) This part describes the approach to typical hazard and risk assessments that need to be performed to define the safety functional requirements and the safety integrity level for each instrumented safety function; d) This part describes the techniques that can be used to determine the required safety integrity level/ Measures; e) This section provides a framework for establishing safety integrity levels, but does not specify the safety integrity levels required for special applications; f) This section does not give examples of requirements for determining other risk reduction methods. Appendix B, Appendix C, Appendix D, Appendix E, and Appendix F describe various quantitative and qualitative methods and have been simplified to illustrate the underlying principles. These appendices are included in this section to illustrate the general principles of these methods but do not provide a definitive calculation. NOTE: If you intend to use methods such as those indicated in these appendices, you should consult the original sources cited in each appendix. Figure 1 shows the overall framework of GB/T 21109 and points out the role this part plays in realizing the functional safety of safety instrumented systems. Figure 2 gives an overview of risk reduction methods.
IEC 61511-3:2003 history
0000 IEC 61511-3:2016 RLV
2004IEC 61511-3:2003/COR1:2004 Corrigendum 1 - Functional safety - Safety instrumented systems for the process industry sector - Part 3: Guidance for the determination of the required safety integrity levels
2004IEC 61511-3:2004 Functional safety - Safety instrumented systems for the process industry sector - Part 3: Guidance for the determination of the required safety integrity levels
2003IEC 61511-3:2003 Functional safety – Safety instrumented systems for the process industry sector – Part 3: Guidance for the determination of the required safety integrity levels (Edition 1.0; Incorporates Corrigendum 1: 10/2004)