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InstMC FS2016 (Rev 3.0)
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3
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Nicol Instrument Engineering Limited
Abbreviations
There is a few notable change with deletions and additions that match ‘Terms and Definitions’, and
also the following additions.
AP
Application program
FSA
Functional safety assessment
MPRT
Maximum permitted repair time
MRT
Mean repair time
MTTR
Mean time to restoration
PFH
Probability (average frequency of dangerous failures) of failure per hour
SC
Systematic capability
Clause 5: Management of functional safety
Organization and resources
This edition adds the requirements for a procedure to be in place to manage the competences of all
those involved in the SIS life cycle. It also requires that there are periodic assessments carried out to
document the competence of those individuals against the activities they are performing, and on any
changes of an individual within a role.
Safety planning
This edition adds a requirement for the safety planning to be carried out to a detailed activity level
that is commensurate with the role the individual or organization is performing. It also notes that this
safety planning can be incorporated into the quality plan with title “SIS Safety Life-cycle Plan”; or as a
separate document with the title “SIS Safety Life-cycle Plan”.
Implementing and monitoring
This edition requires any supplier who makes any functional safety claims for a product or service,
which is used to demonstrate compliance with the requirements of this part of IEC 61511 to have a
functional safety management system. This will include procedures to demonstrate the adequacy of
the functional safety management system, and this functional safety management system meets the
requirements of IEC 61508.
It also includes the requirement for the user to define the necessary corrective action to be taken if
the failure rates are assessed as greater than what was assumed during design phase.
Assessment, auditing and revisions
This edition provides greater emphasis on Functional Safety Audits (FSA), and provides more details
on the requirements and implementing them.
Functional safety assessment
The procedure for the FSA shall cover every SIF within the SIS.
Similar to project design engineering phases (stages 1, 2 and 3) the FSA team assessing the operation
and maintenance of the SIS (for stages 4 and 5) shall include at least one senior competent person
who is not involved in operation and maintenance.
This edition explains that all phases of the safety life-cycle requires an FSA, and if a previous stage has
not been assessed then the current FSA shall include the previous stages in the review. E.g. if an FSA
has not been carried out at stages 1 and 2, then at stage 3 the FSA must include the previous stages