Section 12(3) in The U.P. Cinematograph Rules, 1951
(3)When windows or skylights which provide internal ventilation have to be darkened or obscured, free permanent ventilation shall also be provided through ridge or ceiling ventilators. The clear opening of such ventilation shall be not less than one square foot for every ten Persons accomodated:Provided that the Licensing Authority may relax the condition in the case of buildings already constructed and having sufficient ventilation otherwise, if the extra ventilation is likely to prove very expensive.
