Plenum Areas

[llmay]

What if any is the size limit for a non-plenum rated material to be used in a plenum environment? For example, the plastic retainer strips that come with J-hooks, or nylon pull string.

 

[ryan_618]

Re: Plenum Areas

2000 IMC, section 602.2.1, Materials exposed within plenums. ...materials exposed within plenums shall be non-combustible or shall have a flame spread index of not more than 25 and a smoke developed index of not more than 50 when tested in accordance with ASTM E 84.

No size limitations.