The HazOp is required by OSHA's Process Safety Managment (PSM) regulations. LOPA is a subset of the HazOp procedure when the consequence of some "what if" scenario raised in the HazOp has the "highest" or "most severe" outcome such as loss of life, impact beyond the fence line, major fire, etc...
Thanks for the replies. This was a recommendation from an older HazOp, so the contract facilitator is long gone. Obviously, the "challenge" to supply the appropriate code or guideline reference should be done in future HazOps when issues like this come up. I think the guy was either confusing...
During a prior HaZop of a refinery process unit (a H2SO4 Alky), it was stated (I assume by the facillitator) that even though the PSV on the isobutane surge drum was adequately sized for the controlling fire case, API codes now required dual PSVs, so a second PSV should be added. I can't find...
