Can I use Unclassified Electircal Equipment in a Room that Contains Flammable Liquids and Vapors for Analysis?

[soriajxs]

My objective is to figure out, if with proper mitigations in place, whether I can use unclassified electrical equipment in C1D2 analyzer room.

Sub-Section 8.2.8.2.4 falls under 8.2.8.2 Rooms or Buildings Containing Process Streams of Flammable Liquid, Vapor, or Flammable Gas Piped into the Room or Building for Analysis. My understanding is that this section is for analyzer buildings, laboratories, knock engine rooms etc. which contain source(s) of flammable gases and vapors. However when one reads 8.2.8.2.4 regarding adequate ventilation and gas detection, it refers us to Annex G in order to be able to utilize electrical equipment suitable for unclassified locations.

However when I read Annex G.2b, it clearly states that the interior of the building Does Not Contain a Source of Flammable Gas or Vapor. I am probably misunderstanding this but seems contradictory again, 8.2.8.2 is talking about buildings containing flammable gas and vapors but Appendix G say does not contain a source of flammable gas or vapors. Can someone please help me clarify this? Thx

 

[soriajxs]

My objective is to figure out, if with proper mitigations in place, whether I can use unclassified electrical equipment in C1D2 analyzer room.

API RP500: Sub-Section 8.2.8.2.4 falls under 8.2.8.2 Rooms or Buildings Containing Process Streams of Flammable Liquid, Vapor, or Flammable Gas Piped into the Room or Building for Analysis. My understanding is that this section is for analyzer buildings, laboratories, knock engine rooms etc. which contain source(s) of flammable gases and vapors. When one reads 8.2.8.2.4 regarding adequate ventilation and gas detection, it refers us to Annex G in order to be able to utilize electrical equipment suitable for unclassified locations.

However, when I read Annex G.2b, it clearly states that the interior of the building Does Not Contain a Source of Flammable Gas or Vapor. I am probably misunderstanding this but seems contradictory again, 8.2.8.2 is talking about buildings containing flammable gas and vapors but Appendix G say does not contain a source of flammable gas or vapors. Can someone please help me clarify this? Thx

 

[rbalex]

I'm going to point you to NEC Subsection 500.5(B)(2) IN No 2. [It’s after 500.5(B)(2)(3) but applies to the whole Subsection] Essentially, it is saying a room with gas piping in it Isn’t necessarily classified. There are many factors to consider.

 

[rbalex]

As it applies to the OP, if, after all the factors are considered, and the room is Class I Division 2, then you must construct to Division 2.