Excerpts from the 2006 New Jersey Building Code
(similar to other states and jurisdictions)
Where standby power is connected to elevators, the machine room ventilation or air conditioning shall be connected to the standby power source.
SECTION 3004 HOISTWAY VENTING
3004.1 Vents required.
Hoistways of elevators and dumbwaiters penetrating more than three stories shall be provided with a means for venting smoke and hot gases to the outer air in case of fire.
- In occupancies of other than Groups R-1, R-2,1-1,1-2 and similar occupancies with overnight sleeping quarters, venting of hoistways is not required where the building is equipped throughout with an approved automatic sprinkler system installed in accordance with Section 903.3.1.1 or 903.3.1.2.
- Sidewalk elevator hoistways are not required to be vented.
3004.2 Location of vents.
Vents shall be located at the top of the hoistway and shall open either directly to the outer air or through noncombustible ducts to the outer air. Noncombustible ducts shall be permitted to pass through the elevator machine room, provided that portions of the ducts located outside the hoistway or machine room are enclosed by construction having not less than the fire protection rating required for the hoistway. Holes in the machine room floors for the passage of ropes, cables or other moving elevator equipment shall be limited so as not to provide greater than 2 inches (51 mm) of clearance on all sides.
3004.3 Area of vents.
Except as provided for in Section 3004.3.1, the area of the vents shall not be less than 3½% of the area of the hoistway nor less than 3 square feet (0.28 m2) for each elevator car, and not less than 3½% nor less than 0.5 square feet (0.047 m2) for each dumbwaiter car in the hoistway, whichever is greater. Of the total required vent area, not less than one-third shall be permanently open. Closed portions of the required vent area shall consist of openings glazed with plain glass not greater than 0.125 inch (3.2 mm) in thickness.
The total required vent area shall not be required to be permanently open where all the vent openings automatically open upon detection of smoke in the elevator lobbies or hoistway, upon failure and upon activation of a manual override control.
3004.3.1 Reduced vent area.
Where mechanical ventilation conforming to the International Mechanical Code is provided, a reduction in the required vent area is allowed provided that all of the following conditions are met:
- The occupancy is not in Group R-1, R-2,1-1 or 1-2 or of a similar occupancy with overnight sleeping quarters.
- The vents required by Section 3004.2 do not have outside exposure.
- The hoistway does not extend to the top of the building.
- The hoistway and machine room exhaust fan is automatically reactivated by thermostatic means.
- Equivalent venting of the hoistway is accomplished.