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I've found a series of ethernet cables running through various exposed* areas in my house and I'm wondering how to tell if they are plenum grade.

*exposed areas are running through duct work and along the base board from the duct vent.

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migrated from Oct 25 '12 at 16:47

This question came from our site for professional and enthusiast programmers.

if i am getting you properly other wise tell me

Look for CMP(means Communications Plenum Cable) ,CL3P(Shielded Multi-Conductor Plenum Security Cable) , or CL2P(Class 2 plenum cable ) marked on the cable.

Plenum cable is covered with a fire proof plastic layer of either a low-smoke polyvinyl chloride (PVC) or a fluorinated ethylene polymer (FEP).

  1. Plenum cable must not burn easily
  2. Plenum cable must not emit toxic fumes when exposed to extreme heat
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that's the definition of "plenum" but does not help him determine if a given cable IS plenum or not. – Jason Oct 25 '12 at 15:31
How do I tell if its PVC or FEP? I'd rather not actually test whether it burns ;) – hafichuk Oct 25 '12 at 15:31
@hafichuk see updated answer – NullPointer Oct 25 '12 at 15:38

It may have a "CMP" designation on it. If it has a "CM" or "CMR" it is not plenum rated.

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