This chapter is a case study based on a typical gas detection system. It provides an example of the safety-integrity targeting described in
Chapter 22. The topic is fully covered in
The Safety Critical Systems Handbook, D. J. Smith and K. G. L. Simpson, 4th edition, ISBN 978-0-12-805121-4.
Assume that our gas detection system has the primary function of providing an executive action input to some other ‘Emergency Shutdown’ system in order to protect a chemical process plant. This ESD system will close valves in order to isolate the flammable gases so as to prevent ...