API RP500 Ventilation Requirements - Gas Compressor Stations

[bobgorno]

A question has come up recently about codes and standards applicability in gas compressor stations for electrical area classification and ventilation requirements. Some of us feel API RP500 is applicable, and is considered a national consensus standard. Others feel, that since a state has adopted the International Building Code, the IBC is applicable and over-rides other national consensus standards. Some of us think that this would be over-restrictive for non-occupied or minimally occupied spaces and probably does not apply.

Using IBC requirements would seem to negate any chance of using fugitive emissions calcs, natural ventilation, etc., (not to mention the can of worms it would open for other systems). Think of the new energy crisis when they all shut down....................

Any opinions? Any idea on who the AHJ in the great state of TX would be for such an opinion?

Thanks,
Bob

 

[rbalex]

I’m certainly comfortable using API RP500 as the basis for general electrical area classification applications. You have also correctly identified it as a national consensus standard since it has ANSI sanction.

Of course a jurisdiction can adopt just about any Standards it chooses unless it is overruled buy an even higher jurisdiction.

Truthfully, I was unaware IBC addresses electrical area classification beyond references to the NEC, which in turn references RP500.

 

[bobgorno]

Truthfully, I was unaware IBC addresses electrical area classification beyond references to the NEC, which in turn references RP500.

Bob,

I was a little unclear on the IBC reference in my OP. It is my understanding that IBC requires mechanical ventilation for "H" occupancies. We of course may want to use fugitive emissions and natural ventilation to consider ourselves "adequately ventilated". The electrical dept. and the HVAC dept. are locking horns on this one.


Thanks for you quick response. it is appreciated.

Bob G.

 

[rbalex]

What Section of the IBC are they citing?

 

[bobgorno]

IBC 2003 414.3 and IFC 2003 [F] 502.8.1.1 and [F] 502.8.2

 

[rbalex]

I couldn't find the IFC references, but it doesn't matter; the IBC reference is pretty definitive. I don’t agree with it – but it is definitive.

However, whether the ventilation is natural or mechanical shouldn’t change your electrical area classification. The “pain” is providing emergency power per 414.5.4.

These ICC rules are grossly excessive; they often are – what else can I say? I beleive it is one reason they have trouble getting ANSI sanction, they aren't consensus standards.

 

[bobgorno]

I have two "pains".

Pain One is the quagmire this has become. I have one entity that wants to do 6 air-changes, natural ventilation in a >1000 cu.ft. building, that has inadequate gas detection systems. The other entity says they want mechanical ventilation.

I had suggested leaving the ventilation as inadequate, or, do fugitive emissions calcs, and >3 air-changes natural ventilation. In both cases, upgrade the gas detection system to meet API RP500, 6.5. Done deal you would think?!!?? Are the days of relying on a gas detection system gone?

Pain Two is, in these days of bailing wire and duct tape fixes, who is going to spend money on an EM generator for every gas compressor site? Heck, the only reason they have a building is to keep the cold out in winter.

How many AHJ's really understand this?

I think I can find a good, less challenging job demolishing these buildings so we don't have to worry about IBC:wink:


Sorry, the other references were actually IMC 2003.

Bob G.