Chapter 22

Integrity of Safety-Related Systems

Abstract

This chapter introduces the needed for discrete levels (safety integrity levels) in order to rank the qualitative activities deemed to minimise systematic failures. Low and high demand safety functions are explained and the allocation of SILs across the functions is illustrated. The arbitrary ‘safe failure fraction’ metric is explained. Some current guidance documents are described and the framework for certification is outlined.

Keywords

safety-related
safety-critical
SIL
integrity
qualitative
fraction
safe-failure-fraction
PES
certification
This chapter is a brief introduction to safety-related systems. The Safety Critical Systems Handbook, D. J. Smith and K. G. L. Simpson 4th edition, ...

Get Reliability, Maintainability and Risk, 9th Edition now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.