Historical Minute - August 2013
“In the ventilation of theaters by the upward system, the space under the auditorium is used as a plenum chamber, and there are openings under the seats or in perforated chair legs. In this way each person receives an individual air supply, which, after passing over him, ascends to the ceiling, where the vitiated air is drawn off by means of an exhaust fan. Such systems require only about twenty cubic feet of air per occupant per minute to give good results….
“Particular attention must be paid to the exhaust ventilation of foyers and smoking-rooms, in order to insure an inward current of air into these rooms through doorways or other openings. It is practically impossible to secure proper ventilation of theaters without employing fans.”
—Ventilation of Buildings by William Snow and Thomas Nolan, 1906