608 / 975
3
Disclaimer:
The content in this paper is loosely based on experiences, and have been embellished to bring out the salient points
against the objectives of this paper.
As an end user does your company have or employ the organizations, processes and competences that
directly maps to Figure 1? Or as an end user does your company have or employ the organizations,
processes and competences that may map those in Figure 1?
Note the question did not focus on projects as Figure 1 covers all stages and life-cycle. For projects only
a few of the clauses are covered, typically clauses 5 through 15, but can include clauses 17 and 18. For
end users all clauses apply.
As an end user are all the clauses applicable to you?
Discussion
For Greenfield (e.g. a new site) the clauses 5 through 15 usually have more than one company,
organization or disciplines involved. That is the end user identifies the project requirement and may
contract out to an EPC (Engineering Procurement contractor) for the design and maybe another
contractor for the construction. As SIS is part of Functional Safety there are multi-disciplines involved in
these companies. There is also the equipment manufacturers’ who must meet the requirement
specification.
There are international standards such as IEC 61511, and others, and possibly end user company
standards.
All this provides multiple interfaces and information transfer that require to be managed. Back to the
football analogy, if the ball is not under your control and you try to pass it then it may not go where you
intended.
Whilst there are multiple interfaces and complexity for Greenfield projects these generally can be easily
managed for delivering Functional safety.
Modifications and decommissioning brings other challenges. Modifications can be from small changes to
Greenfield projects adding to Brownfield processes. It can also include elements of decommissioning
where the equipment for decommissioned functions is re-used with changed functionality.
Modifications has similar multiple interfaces, standards etc. as for Greenfield, but with added interfaces
and complexities with connections to the Brownfield equipment and from operational constraints.
The intent of the following case studies is to show where things can go wrong, and where it could be
said it was a team of individuals and not an individual team.
Case 1: Loss of containment detection from low pressure detection
Some international standards suggest the use of low pressure detection for the identification of loss of
containment from leaks.