Are pipe sleeves required for low voltage cabling passing through slab?

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it all depends on the particular fire stop system being used. All of the fire stop systems have very specific instructions, often come with a label that gets placed by the assembly, how many conductors, type of sleeve.
 
Thanks that's a good point relating to fire stopping requirements. But aside from that, does the NEC require low voltage or fire alarm cables to be protected with a pipe sleeve when passing through concrete?
 
There is very little in the NEC about fire stopping and nothing that I know of relating specifically to concrete. I seem to recall firestopping info in Art 300 but limited time prevents me from getting specific section
And now you mention fire alarm. Fire alarm cable require physical protection and treated differently from limited energy. Art 760 is not my strong area. So with fire alarm you may be required to have a sleeve.
I would sleeve anyway to protect cables from damage
And lastly, most fire stopping is inspected by the building dept.
 
cppoly said:
Thanks that's a good point relating to fire stopping requirements. But aside from that, does the NEC require low voltage or fire alarm cables to be protected with a pipe sleeve when passing through concrete?
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are the cables direct burial rated? If not, then when in concrete you need conduit... remember, concrete moves and it wicks moisture...
 
cppoly said:
Thanks that's a good point relating to fire stopping requirements. But aside from that, does the NEC require low voltage or fire alarm cables to be protected with a pipe sleeve when passing through concrete?
Click to expand...

This will be covered more by your local building codes than the NEC. In New York, I would be very surprised if fire alarm cabling could pass through a core drill without a sleeve or full conduit, or at the very least fire stop. properly firestopping a bunch of cables going through a vertical penetration is not always the easiest thing to do.

I do believe that they make two-piece sleeves that can be placed around existing cabling if that is what you are facing. Check with a company like STI, Hilti, or 3M.

I have run Communications cables thru non sleeved vertical core drills, though no fire alarm cabling, and that was in the South 10 years ago.

there is also the matter that all of these cables, if penetrating a floor, would be required to be CMR or CMP rated. If this is a slab on grade, it would be extremely uncommon for the underground conduits not to at least stub up into the building for protection against physical damage. Even if that is not code, it is common sense.
 
dont know if it is still available but there used to be a grey sleeve.. plastic... was used for cable tv, telephone and internet.. I bought all mine at Radio Shack... it was called a through wall bushing and came in a few thicknesses, two piece...Drill the proper hole, push the peice in, have helper push the other piece into it, and the run the cable in through the hole... worked for up to a sixteen inch block wall... and had many sizes as well.
Have not seen it in a few years but was not looking for it.. Now I usually drill through a slab, push in a 10 mm or 15mm conduit as needed, put in my wires and spray foam...piece of conduit is cheap when you only need around 6 inches at a time.
 
I have had to make two "official" penetrations involving fire-stop measures. The first was a generic low-voltage pass through a fire-rated drywall wall. It required a sleeve of EMT with fire caulk both between the drywall and the EMT and in the EMT surrounding the cables.

The second was more involved, with four 3/4" EMT's through a concrete floor. I had to use a layer of mineral wool a specific thickness, topped by a layer of fire caulk. By fire caulk, I'm referring to what I believe is called bituminous caulk, which expands to seal when heated.

If I remember correctly, I found the engineering specs for the fire stopping from the website of the caulk manufacturer. It included a printable page with specs and measurements that I included with the permit application for the job. It's referred to as an assembly.
 
tom baker said:
There is very little in the NEC about fire stopping and nothing that I know of relating specifically to concrete. I seem to recall firestopping info in Art 300 but limited time prevents me from getting specific section
And now you mention fire alarm. Fire alarm cable require physical protection and treated differently from limited energy. Art 760 is not my strong area. So with fire alarm you may be required to have a sleeve.
I would sleeve anyway to protect cables from damage
And lastly, most fire stopping is inspected by the building dept.
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I am also pretty weak on article 760 installations, however I know that chapter 8 cabling must meet the requirements of 300.22, and 800.26 requires Fire Stop in much the same language as 300.21.

800.154 covers the cable types.

I'm sure the same sections are also in article 760, which are probably superseded by New York building codes.
 
Adamjamma said:
are the cables direct burial rated? If not, then when in concrete you need conduit... remember, concrete moves and it wicks moisture...
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There is a difference between embedding something in concrete and running through a bored hole in concrete...

topgone said:
FromNEC:
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:thumbsup:

Need for physical protection is the answer to OP's question, unless firestopping the penetration applies, but he seems to not be concerned with firestopping and wanting a more general rule for passing through concrete.
 
kwired said:
There is a difference between embedding something in concrete and running through a bored hole in concrete...

:thumbsup:

Need for physical protection is the answer to OP's question, unless firestopping the penetration applies, but he seems to not be concerned with firestopping and wanting a more general rule for passing through concrete.
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Thanks guys.

But can I push back a little, if conductors pass through a core drill through concrete why would the conductors not have physical protection? Stupid question, it's not like the concrete is going to collapse. Why would physical protection from a pipe sleeve be required here?
 
cppoly said:
Thanks guys.

But can I push back a little, if conductors pass through a core drill through concrete why would the conductors not have physical protection? Stupid question, it's not like the concrete is going to collapse. Why would physical protection from a pipe sleeve be required here?
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It is not. If the hole is through a floor a certain distance above the floor might be considered subject to physical damage in nearly all cases.
 
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