Wire thru plenum.. LV plenum rated or not?

[ritelec]

Hello..

300.22 C exception mentions that for plenum "other area" a non plenum rated cable (NM) can pass thru perpendicularly.

When I look at LV wiring in 800.154(a) it mentions "in other spaces used for environmental air" as described in 300.22C

I'm assuming that if the LV wiring if not plenum rated like CM or CMX … it would still fall into the 300.22C exception…… and would not need to be plenum rated.,

But after reading thru 725.154(A)………. I then noticed that 800.154(a) actually says "described"

Looking into 725.154 (A) for CL2 and CL3 wire and see that It mentions the other spaces as "described" in 300.22C and goes on to say Only Type CL2P or CL3P cable shall be permitted to be installed in these raceways.

Are they calling the other space a raceway??

Am I to read it that non plenum CM or CL can't go though this other area as NM can, or does the exception of 300.22C also apply to these LV cables?

Thank you.

 

[luckylerado]

The exception you refer to is specifically only for cable within and perpendicular to joist and stud spaces used for environmental air. In that context, the exception would apply to communications cable provided it is at a min listed CMX for a dwelling unit

 

[ritelec]

Thanks for he response.

Please let me confirm. The exception also relates to CL2 and CL3 wire not just the CMX correct ?

 

[luckylerado]

My take is that per the exception, the rules that govern wiring methods within "Other Spaces Used for Environmental Air" 300.22(C)(1) do not apply when installed perpendicular to and within a stud or joist space used as a plenum regardless of cable type.CL2 and CL3 may or may not be suitable for your application but it is not disqualified by 300.22 as I read it.

 

[ritelec]

Okay.

I don't currently have an application for this.

I was just reading and researching and believed any of the HV or LV wiring could go perpendicular

But then as mentioned, both LV wiring mentioned the "description" of the other area but didn't (and I still don't think) say the wiring method would be as in that article and it's exception.

Thanks again.