Functional Safety 2014

ii) Safety function seriously flawed:

will only partly work or work too late

Counter-measures:

•

Clarity and simplicity of design documents – avoid notes on C&E

documents

•

Strong management of change and verification procedures

•

Test each change post-FAT

•

Logic solver vendor competence (for post-FAT changes and site work)

•

Read back signal via HART and compare to scaled analogue

•

Competence – e.g. changes made during operation

Neil Wakeling, August 2014