Life safety
Use of fire doors in buildings -
4.6.1 Smoke exhaust and pressurization of areas above ground
1. Exit access corrdiors of guest, indoor patients, sleeping accommodation, apartments, 
custodial, penal and mental institutions shall have external wall of 60minutes and 
20minutes self closing fire door. 2. All exit passageway (exist to exit discharge) shall be pressurized or naturally ventilated 
and passageway shall have a door of 120min fire rating. 3. Smoke exhaust systems shall be provided in multilevel basement with independent air 
intake. All supply air, and exhaust air fans shall be installed in fire resistance room of 
120minutes. (4.6.2)
4.