HAZOP & Me

HAZOP & Me

And I hate it!!!!

I know linguists will complain that this “&” is used when there is close association between the said items like Black & White TVs, and therefore your title is not correct if you hate HAZOP. I know HAZOP Leaders and scribes would make the same complain as they themselves belief nothing less than a linguist.

So, let’s get back to why I hate HAZOPs. You can see the reasons below that came to my mind in first go: ??

1.??????I am tired of listening that HAZOP Leader is not responsible and in fact not supposed to know technical details of the system: how they work, how they may fail and what would be the consequence in they fail. If the HAZOP is of bad quality, they put the blame on system engineers / process engineers that they didn’t explain the system well. So, what’s your role Mr. HAZOP Chairman? Ask relevant questions and guide the HAZOP workshops but for that you would need basic understanding of the system that is being HAZOPed.

2.??????They love sweeping many hazardous scenarios under the carpet in the name of “Double Jeopardy". Drains for example are generally provided with 2 valves based on Master-Martyr Arrangements. I see “More Flow” through such drain lines are generally ruled out siting double jeopardy meaning how could both valves be failed opened at the same time and thereby causing more flow. ?

3.??????Double Jeopardy is also used as a shield against simultaneous failure of multiple drain line (fail open case) and if you ask them if the concerned system will also be assessed through CHAZOP and they are dumbstruck, CHAZOP!!!!!! What’s this new bird in the town? It reflects your limited knowledge about IEC 61882 and your eagerness to meet HAZOP schedules.

4.??????Alarms alarms everywhere……?if you see a HAZOP worksheet, you will be overwhelmed by how frequently alarm is mentioned. But if you ask what action operator will take against those alarms, if operator would have enough time to identify the cause of alarm and subsequently take the relevant corrective action?? No one wants to go that far. Mention alarm and let the show running!!! ?

5.??????Manual valves left closed after maintenance… this is a usual initiating cause for no flow through manual valves. How about scenario where certain lines are normally closed and needed only during certain phase of the plant say … start-up phase. A better description for such case would be "Operator fails to open XXXX valve during start-up"….. and and the linguist in HAZOP Leader is offended. “We should maintain consistency and not deviate from the initial write up about manual valve failures i.e. "Manual valves left closed after maintenance”. Bull-beet!!!!

6.??????I have noticed varied pump protections against no flow (inlet/outlet of pump being closed) and if you ask supporting documents to confirm claimed protections you are main culprit of HAZOP schedule. You don’t believe what system experts are telling you.

7.??????“Pressure High” scenario is ruled out if the system in discussion is not isolated. What if the pressure relief system is not sized for the cause of the pressure rise? And there would be silence in the room. Again, no supporting documents to verify the claims being made.

8.??????Seldom I see maintenance guys called for HAZOP workshops. They are site people, what role do they have in design offices.

9.??????Participants just don’t accept that a “Fail Safe” valve may also fail. How could it, its a fail safe valve???

Please add in your reasons for hating HAZOP.

Regards, Jay (A newly appointed show runner :) ) ?