The plenum shall be constructed with approved materials and shall remain a dedicated space. Foreign objects such as, but not limited to, plumbing pipe, electrical conduit, phone wires, intercom wiring, low voltage wiring of any kind or insulation, shall not be installed within the return air plenums or ducts.
(Prior Code, § 9-15) (Ord. 90-67, passed - -; Ord. 94-11B, passed 4-21-1994)