schedule 40 pvc

[davidbananas999]

Ive been scouring over 330's etc trying to figure out where I can use schedule 40 pvc to protect nm. My company has us use schedule 80 when penetrating the surface of the ground (thhn etc), and then 40 underground. I think I have also used 40 on basement walls etc. 334.15 B only has 80 listed.

Tips?

thanks.

 

[JFletcher]

Try looking in 352.

 

[kwired]

Ive been scouring over 330's etc trying to figure out where I can use schedule 40 pvc to protect nm. My company has us use schedule 80 when penetrating the surface of the ground (thhn etc), and then 40 underground. I think I have also used 40 on basement walls etc. 334.15 B only has 80 listed.

Tips?

thanks.

How much physical protection is needed? Most places where using NM exposed just having the cable following building surfaces is usually enough physical protection. Running it in a raceway is more for appearance then it actually provides needed physical protection - but this is also a judgement call more so then something clearly mentioned by NEC.

If you go a little further into 334.15 you will find in (C) it says "Nonmetallic-sheathed cable installed on the wall of an unfinished basement shall be permitted to be installed in a listed conduit or tubing..." That should include sch 40 PVC as is worded. If an AHJ wants sch 80 they should have a good reason to say the amount of possible physical damage is severe enough to warrant it, IMO.