Answer
The current edition of the functional safety standard (IEC 61511:2026) isn’t clear on this point, but if an approach is taken where functional safety management (and the need to define and control competency) is only applied when the conclusion of the study is “SIL required”, then this implies prescience (you know what conclusion of the study will be before you start - and can plan accordingly). This also implies that where a SIF is specified, this must be tightly controlled, whereas if no SIFs are required, there are no such constraints, which is clearly incorrect!
At =Method we think Functional Safety Management is simply good engineering practice – so we encourage clients to follow FSM on all HazOp studies, irrespective of the conclusion (by developing a simple safety plan to cover the scope of the work, verifying the output and carrying out a limited scope functional safety assessment before accepting the conclusion of the study). This approach isn’t onerous and gives confidence that the conclusion of the study is correct.
