sealing of conduits

Status
Not open for further replies.
bob nowinski said:
What are any requirement of the NEC regarding the sealing of conduits through walls?
Click to expand...
The NEC doesn't require much, see 300.21.

This is more of an architectural, building code, and/or UL assembly issue.

Roger
 
There are no general sealing requirements for walls but there are several specific ones:
  • 300.21 as noted.
  • 300.7 for raceways exposed to temperatures
  • Several water seals for underground entries; e.g. 225.27
  • Where a wall may be a boundary in classified locations; e.g. 501.15(A)(4) or (B)(2)
These are not exhaustive; it would help to know the specific application.
 
bob nowinski said:
What are any requirement of the NEC regarding the sealing of conduits through walls?
Click to expand...

Can you give us a little more info on the walls and the conduit?
Exterior, interior, firewall, fire rated partition, above grade, u/g, corridor, wall separating garage and sleeping area, occupancy separation, tenant separation, ...it's endless.
 
Sealing Conduits

Sealing Conduits

I don't know about the codes but one thing I do know is that I have seen a lot of damage rodents can cause in switchgear due to unsealed conduits. In LV and especially MV gear. Heavy gauge doors blown off their henges because a rat bridged a conductor to ground on a PT or fuse truck. That is why in our inspection reports we recommend sealing all conduits. A very cheap solution to what can be a very expensive disaster.
 
Status
Not open for further replies.
Top