Sealoff locations

[timdiamondz]

501.15(A)(4) requires a sealoff where conduit is "leaving a Class I, Division I location". 501.15(B)(2) requires one where conduit is "passing from a Class 1, Division II location into an unclassified location". What about conduit passing from a Div I into a Div II area? I interpret both articles to require a sealoff at this "boundary" also.

 

[rbalex]

Section 501.15(A)(4) applies at any Division 1 boundary and therefore applies at a Division 1/Division 2 boundary. Section 501.15(B)(2) only applies at a Division 2/Unclassified boundary.

 

[jbelectric777]

i dont know if this matters in your situation but no seal fitting is required if the conduit is just passing through from classified to non classified and there are no fittings. couplings engaging 5 threads may be an exception, my point is i had the same thing with a 2.5" rigid rubber coated which is a bitch to clean and thread, it was a poop plant where the freshest of the fresh comes to be cleaned !!! i was running from the hazardous area right through a small control room and my partner was gettn ready to cut,clean & thread when i thought, wtf that makes no sense. and saved me about 2 man hrs, seal compound, 2 seals rubber coated rigid, hey it adds up. and while were on the subject i have more work comin up there, i dont have my book here but did i hear correct some hazardous locations are going to start allowing PVC ? in 2011, or is that just a 2011 request

 

[rbalex]

... while were on the subject i have more work comin up there, i dont have my book here but did i hear correct some hazardous locations are going to start allowing PVC ? in 2011, or is that just a 2011 request

There are a few, very limited, Division 2 applications permitted; they were introduced in the 2008 NEC [501.10(B)(1)(7)]