| EXCEPTIONS: | 1. Use of a corridor as a source of makeup air for exhaust systems in rooms that open directly onto such corridors, including toilet rooms, bathrooms, dressing rooms, smoking lounges and janitor closets, shall be permitted provided that each such corridor is directly supplied with outdoor air at a rate greater than the rate of makeup air taken from the corridor. |
| 2. Where located within a dwelling unit, the use of corridors for conveying return air shall not be prohibited. | |
| 3. Where located within tenant spaces of one thousand square feet (93 m2) or less in area, utilization of corridors for conveying return air is permitted. | |
| 4. Where such air is part of an engineered smoke control system. | |
| 5. Make up or relief air in corridors of Group I-2 occupancies. | |
| 6. Corridors serving residential occupancies shall be permitted to be supplied without specific mechanical exhaust subject to the following: | |
| 6.1 The supply air is one hundred percent outside air; and | |
| 6.2 The units served by the corridor have conforming ventilation independent of the air supplied to the corridor; and | |
| 6.3 For other than high-rise buildings, the supply fan will automatically shut off upon activation of corridor smoke detectors which shall be spaced at no more than thirty feet (9,144 mm) on center along the corridor; or | |
| 6.4 For high-rise buildings, corridor smoke detector activation will close required smoke/fire dampers at the supply inlet to the corridor at the floor receiving the alarm. |