<hardware> Cable that can be (legally) installed in the plenum (the space between a ceiling and the floor above it). Such cable is (usually) teflon-coated so that it will not give off toxic fumes when burned. In some parts of the world such cable is required by law.
Last updated: 1996-08-25
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Nearby terms: PL/C « PL Cornell « PLD « plenum cable » pleonasm » plesiochronous » Plesiochronous Digital Hierarchy