Section 38

The doors of the enclosure and rewinding room and all openings, bushes and joints shall be so constructed and maintained as to prevent, as far as possible, the escape of any smoke into the auditorium. Ventilators shall be provided for the enclosure and for the rewinding room but the ventilation ducts shall not communicate direct with the auditorium. The area of the ventilating ducts of the enclosure shall not be less than one per cent of its floor area.
Explanation :- By 'bush' is meant packing inserted in the holes through which the pipes and cables, pass in order to render such holes reasonably smoke proof.