Sealing cable gland needed? (Class I Div II)

[rbalex]

I was referencing a purged enclosure, with 120vac in it, in a classified area. Not the solenoid itself, its already epoxy poured/sealed

It isn't relevant to the OP. However, see Section 501.15(B)(2) Ex No 3. In the case you described, an enclosure seal most likely wouldn't be needed if the pressure/purge system were appropriately designed. I say, “most likely”, because I don’t know the full scope of the design.

In 2014 we had an Arc Flash audit that required us to purge our enclosures, with 120 in them.

Honestly, this sounds like overkill by someone not fully qualified to make the call. Again, to be fair, I don’t know the underlying reasoning that would lead to requiring purging an enclosure simply because it had 120V in it or how an arc flash study would lead to it.

 

[4-20mA]

Me either, which is mostly why I asked. Thanks for the reference though. My bad for derailing the thread

 

[TwoBlocked]

Here is a link to a Topic on wiring in oxygen enriched atmospheres:

Oxygen-Enriched Atmosphere

Dear Moderator, I tried to send this question before but have no idea, if it reached you. If yes, please discard this question. I could not find any references in NEC that the oxygen storage tank area is considered a hazardous location. However, NFPA 53 Chapter 7 requests that electrical...

forums.mikeholt.com

 

[rbalex]

I responded in that thread also and said:

Oxygen enrichment can obviously exacerbate the conditions in an already classified location, but it alone will not create one.
I reviewed NFPA 53, Section 7.7 and found that using Division 1 installations [sic] techniques wouldn’t make any difference, especially in light of the explanatory material in Appendix A, Section A.7.7.1

It has been my observation over the years that many people not sufficiently familiar with proper Hazardous Location practices will opt for excess both classifying a location and installing more than necessary.