Exhaust Duct 2 : A pipe that conveys used or exhausted air from an occupied space either outside or to the fan room or machinery room for reconditioning
Ralph W. Burklin & Robert G. Purington, Fire Terms: A Guide to Their Meaning and Use, National Protection Association, Boston, MA 1980 USA. (Guide: Meaning and Use, Nat Prot Association Fr Srvc - Amer) {457}