ENT Question

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Can ENT (smurf pipe) be run through a firewall and treated as EMT? Or is this a violation? I haven't been able to find a definate shall not so far.
 
as far as I know pentrateing a fire wall is not an NEC issue it falls under the building code and the fire safty code inforced by the Fire Marshal

EMT is normally easiest to fire stop some fire caulk properly applied around conduit and that is it

PVC and ENT take a little more protection and special items to properly fire stop

contact 3M and have them send you a catalog of all their firestoping devices they may even send a sales rep to explain how they are applied

contact the Fire marshal in your area and ask them. you can get the phone number from the NON-EMERGENCY phone number of the fire department or police

In answer to your question YES ENT can penatrate a fire wall it just needs to be properly sealed which is costly and a pain to do
 
362.10(1)b concealed within walls,floors,and ceilings

362.10(5) ... as identified in listings of fire-rated assemblies... to keep the fire-rating of your fire wall where ENT penatrates said fire wall is costly but possible it also has to be done while the fire wall is being built it is so much easier to set a J-Box run EMT or FMC through the firewall set another J-Box and continue your run. ENT and PVC require a much more elaborate fire stopping procedure. requireing fire-wool, sleeves, fire putty, and fire-caulk. there are also listed assemblies for ENT fire wall penatrations. if it were not permitted why would they make a listed assembly for the purpose.

362.12 Uses not permitted fire-walls are not listed

if you follow all the other rules for ENT it can penitrate a fire wall it is just not a good idea because of the work and cost involved to properly do it

so I still say that can ENT penitrate a fire=wall? YES
 
Assuming that you meet all the other requirements for using ENT (like the ones Frank mentioned), you would still have to install the ENT as a UL listed assembly. (You can search the UL listed assemblies online, and see if there is something that uses ENT going through a firewall).

Assuming that you find an assembly in the UL guide, it would probably still just be easier to use EMT.

And for a more direct answer to your question, no you can't just treat ENT like EMT. The UL guides are very specific to what components are used. (Don't forget, even the EMT has to be installed to meet a UL listed assembly. That will probably limit the size of the hole, and require firestopping compound around the conduit.)

Steve
 
Thanks Steve. Your comments are pretty much what I was thinking. I can't see ENT being a plastic equivalent of EMT. The NEC recognizes inherant inablilities of a variety of products in their applications. I, even without a coherent reference, can't help but feel that PVC is just not suitable to go through a firewall treated same as EMT.

I guess it boils down to finding the UL rated assembly for proper installation. That sounds correct too. That was a big help to me in direction to look.
 
As a follow up to this, I'm told by a certified fire engineer, Hilti, Carlon - an ENT manufacturer, and 3M that ENT (smurf pipe) can be run through, up to a two hour wall, much the same as EMT. It has to be caulked much like EMT and a number of companies provide caulk for this purpose. 3M and Hilti do for sure, I checked.

Of course it still can't be used in a plenum per NEC or in a non sprinklered building more than 3? floors (I think it is right off the top of my head). Thanks for the help guys, this one really stumped myself and a number of other electricians working with me on it.
 
can't help but feel that PVC is just not suitable to go through a firewall treated same as EMT.
I don't see a lot of difference...they both will permit the fire to spread through the rated wall unless the penetration is firestopped.
Don
 
The difference is the method of firestopping. ENT melts leaving a hole that must fill by a firestop method that will expand to fill, whereas EMT doesn't. The type of firestop required by each is different. But overall you're right, both can penetrate a two hour wall so long as the proper sealant is used.
 
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