Hazardous Location Issue, Gas Valves

[Plant Operations]

I have a question about hazardous locations concerning NFPA 58, Table 6.20.2.2, Part J. Part J is the reference for pipelines and connections containing operational bleeds, drips, vents, or drains and how equipment should be rated for the extent of the classified area (Class 1, Div 1 within 5ft and beyond 5ft from point of discharge is treated as Part F of the same table). What is not specifically addressed in this information is equipment such as gas valves ( for connecting propane hoses for torches, etc). I am interpreting this information to include gas valves as an item that should be following the same requirements but my electrical engineers and local code official insist that this is not required. Am I going overboard on my interpretation of this requirement? We have had similar discussions with NFPA 54 applications.

 

[petersonra]

Is the gas fired furnace in your basement in a classified area? How about your gas fired water heater?

 

[rbalex]

When discussions of this kind arise, I usually ask (both parties) if the document's scope has been reviewed first.

Is NFPA 58 even the correct Standard to apply? I.e., is this Liquified Petroleum Gas we're talking about? If not, what is the proper standard?

When a piping system permits a not-catastrophic path to atmosphere of unspent fuel, intentionally or otherwise, it is worth a review by someone qualified to do so. It still won't necessarily require electrical area classification since there are many things to consider, but it isn't a casual activity either.

Experience plays a large part in being "someone qualified to do so" and, if the engineers and/or the local official have had substantial experience with similar facilities, I'd be inclined to go along with them.