MC cable firestopping UL interpretation

[Tainted]

I plan to penetrate a 3 hour fire rated wall with 3/0 - 3 conductor + ground MC cable.

I found a firestop submittal (see below and attached) which says this:

3. Cable bundle to be a combination of any of the following:

G. Maxmimum 3/C copper conductors no. 8 Awg metal clad cable
I. Any cables, metal-clad cable or armored cable currently classified under the through penetrating product category.

Why does it have 2 seperate conditions for "no. 8 cable" and "cables under the through penetrating products category"?

What does "through penetrating products category" mean? Does it mean it needs to be rated for fire rated penetrations?

Can I use 3/0 - 3 conductor + ground MC cable even if they say maximum allowed is #8 awg? The 3/0 cable I'm using is classified under the through penetrating products category I believe...

 

[infinity]

What does "through penetrating products category" mean? Does it mean it needs to be rated for fire rated penetrations?

It sounds like for the size of the MC cable that you're running they want a fire rated product to run the cable through. Not just through the wall and then patched with some firestop caulk.

 

[Tainted]

It sounds like for the size of the MC cable that you're running they want a fire rated product to run the cable through. Not just through the wall and then patched with some firestop caulk.

right, but why would they say maximum #8 awg even though we can use 3/0 awg

 

[roger]

For the assembly shown #8 is the largest. The UL orange books will show many other assemblies than just Hilti.

 

[winnie]

As I read the submittal, you have options.

1) You can use _any_ MC cable up to a maximum of 3C+ground #8 AWG.
2) You can use an MC cable classified under the 'through penetrating products' category. When I did a search for 'through penetrating products' I found datasheets for various firestop assemblies, and those datasheets specified the specific MC cable they were listed with. For example, this product from 3M only lists AFC Cable Systems brand MC cable. https://multimedia.3m.com/mws/media/197872O/system-no-w-l-3015.pdf (Other 3M datasheets list other cable manufacturers)

So 'small cables use any, big cables you are limited to specifically listed combinations of firestop and cable'

 

[Tainted]

As I read the submittal, you have options.

1) You can use _any_ MC cable up to a maximum of 3C+ground #8 AWG.
2) You can use an MC cable classified under the 'through penetrating products' category. When I did a search for 'through penetrating products' I found datasheets for various firestop assemblies, and those datasheets specified the specific MC cable they were listed with. For example, this product from 3M only lists AFC Cable Systems brand MC cable. https://multimedia.3m.com/mws/media/197872O/system-no-w-l-3015.pdf (Other 3M datasheets list other cable manufacturers)

So 'small cables use any, big cables you are limited to specifically listed combinations of firestop and cable'

How do I find a 3/0 copper cable that is a "through penetrating product"? How would I know it's a "through penetrating product"?

 

[roger]

How do I find a 3/0 copper cable that is a "through penetrating product"? How would I know it's a "through penetrating product"?

It's not so much the cable as it is the tested assembly. Once again, look at the UL Orange Books (Fire Directory), it's a two book set, the second is for Through Penetrations and has thousands of assemblies.

 

[Tainted]

It's not so much the cable as it is the tested assembly. Once again, look at the UL Orange Books (Fire Directory), it's a two book set, the second is for Through Penetrations and has thousands of assemblies.

I tried googling the book and couldnt find it

 

[roger]

Try this link

Finding UL Listed and Certified Fire-Rated Products with UL Product iQ®

Use these instructions to create your UL Product iQ account and search the certification database for UL fire-rated assemblies, designs or systems.

www.ul.com

 

[roger]

UL may have discontinued it.

 

[Strathead]

Two things. First the UL listing you are quoting is for multiple cable through a single penetration. Your description of what you want to do sounds like a single cable through a penetration, that is a different UL assembly. Second, if you are having trouble use your phone. Spec Seal, 3M, Hilti, etc. all have excellent tech support to find the proper UL for your application. Call them and they will send you to the right assembly immediately

 

[Tainted]

Try this link

Finding UL Listed and Certified Fire-Rated Products with UL Product iQ®

Use these instructions to create your UL Product iQ account and search the certification database for UL fire-rated assemblies, designs or systems.

www.ul.com

It doesn't really explain though what constitutes a cable that is a "through penetration category"

 

[Tainted]

Two things. First the UL listing you are quoting is for multiple cable through a single penetration. Your description of what you want to do sounds like a single cable through a penetration, that is a different UL assembly. Second, if you are having trouble use your phone. Spec Seal, 3M, Hilti, etc. all have excellent tech support to find the proper UL for your application. Call them and they will send you to the right assembly immediately

If this it for multiple cables, why can't I just use 1 cable? Wouldn't that work? Also I tried emailing hilti, all they did was give me a link to their firestopping finder which doesnt help

 

[winnie]

It doesn't really explain though what constitutes a cable that is a "through penetration category"

This is _not_ my area of expertise, and I think the language is kind of convoluted.

I think: The cable itself isn't a 'through penetration category'. Rather the wall penetration is listed in the 'through penetration category' and the datasheet for the penetration shows the cable it can be used with to meet the listing requirements.

-Jonathan

 

[tortuga]

What about 3M fire Mortar? I think the few times I have had to do this I had EMT going thru the firewall but not sure if that matters.

 

[Tainted]

This is _not_ my area of expertise, and I think the language is kind of convoluted.

I think: The cable itself isn't a 'through penetration category'. Rather the wall penetration is listed in the 'through penetration category' and the datasheet for the penetration shows the cable it can be used with to meet the listing requirements.

-Jonathan

does this mean I cannot use 3/0 MC cable?

 

[roger]

If this it for multiple cables, why can't I just use 1 cable? Wouldn't that work? Also I tried emailing hilti, all they did was give me a link to their firestopping finder which doesnt help

The assemblies are tested for each scenario, one conduit, multiple conduits, one cable, multiple cables, etc.... the one you use will need to be supported by an assembly.

As Strathead said, try multiple manufacturers, Hilti is just one of many and I have found some of the others to be more accommodating than Hilti.

 

[Strathead]

If this it for multiple cables, why can't I just use 1 cable? Wouldn't that work? Also I tried emailing hilti, all they did was give me a link to their firestopping finder which doesnt help

Don't email call Hilti. 1-800-879-8000 I promise they won't disappoint.

To answer your question. because just like the code, it means what it says. In this case "any combination" is not one cable. Firestopping has become very precise in the last 20 years.

 

[Strathead]

The assemblies are tested for each scenario, one conduit, multiple conduits, one cable, multiple cables, etc.... the one you use will need to be supported by an assembly.

As Strathead said, try multiple manufacturers, Hilti is just one of many and I have found some of the others to be more accommodating than Hilti.

But they aren't. Hilti and Spec Seal are the best in my experience. Not to discount any others. Just I have had personal experience with both of these and they were as helpful as one could expect.

 

[roger]

Firestopping has become very precise in the last 20 years.

Before I retired I used firestopping contractors for most jobs, it was actually cheaper in the long run.