ISA84 Audit Process

[NewMechanicalEngr]

We will soon be going throughout our facility to determine whether our safety systems are ISA84 compliant and I would like to get some of your thoughts on what they audit process should consist of.

1) I suppose the first thing is to make sure we can identify which items fall under ISA84. I put another post out about this, but there may be ESDs that are in place for code compliance and NOT necessarily for specific quantified risk reduction. If that is the case, then would these ESDs need to meet ISA84 requirements?

2) For those that do fall under ISA84, then I suppose we would get as much background information. What was the desired risk reduction factor, were SIL calcs done to confirm the design achieves the RR needed, what is the test interval, is there a functional test plan, is it being tested as often as needed?

3) Lastly, I think would be the development of a findings report explaining to management what deficiencies were found and remedies needed.

Please share your thoughts on the above!!!

Thanks!!!

 

[controlnovice]

Your plan is sound.

It's possible that systems are grandfathered.

For those systems considered ESD, whether code compliance or risk reduction, you may want to consider a PHA re-validation of that node not taking into consideration any existing safeguards, then perform a LOPA of those scenarios that are deemed high risk.

Performing the LOPA will help determine if the current safeguards offer the needed protection per your company's risk reduction goal. From this you can determine if the current ESD risk reduction is fulfilling your company goals.

Be careful though. I've run into a few SIS/ESD installation that were installed when not required when performing a LOPA. An incident happened in another facility and they installed an SIS system and management determined that all facilities will have an SIS system for the same process, even though equipment differences and current safeguards were adequate risk reducers. You don't want to suggest to management that an ESD (typically very expensive) was installed for little to no improvement to safety.

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[NewMechanicalEngr]

Thanks for the feedback. I too was thinking of looking at a LOPA without the ESD's to see whether the node "required" the ESD, which in my understanding would mean its purpose is for risk reduction and therefore would make it fall under ISA84.

You agree?

On a related note, what if we consider a fired heater built to NFPA standards. The BMS would include ESD functionality. Would you automatically consider this BMS an SIS and would it fall under ISA84?

Thanks again for sharing your knowledge on this topic.

 

[controlnovice]

If the ESD was required by LOPA to obtain the total risk reduction, then yes, you can envelope it in ISA84.

Read the document below to better understand BMS and SIS:

http://www.isa.org/Content/Microsit...004_Safety_Papers/Industry_Update_SIS_BMS.pdf

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This is normally the space where people post something insightful.