18-28-502.7.1.1 System requirements.
   Exhaust ventilation systems shall comply with all of the following:
   1.   The installation shall be in accordance with the Chicago Building Code.
   2.   Mechanical ventilation shall be provided at a rate of not less than 1 cfm/ft2 [0.00508 m3/(s x m2)] of floor area over the storage area.
   3.   The systems shall operate continuously unless alternate designs are approved.
   4.   A manual shutoff control shall be provided outside of the room in a position adjacent to the access door to the room or in another approved location. The switch shall be of the break-glass type and shall be labeled: VENTILATION SYSTEM EMERGENCY SHUTOFF.
   5.   The exhaust ventilation system shall be designed to consider the density of the potential fumes or vapors released. For fumes or vapors that are heavier than air, exhaust shall be taken from a point within 6 inches (152 mm) of the floor.
   6.   The location of both the exhaust and inlet air openings shall be designed to provide air movement across all portions of the floor or room to prevent the accumulation of vapors.
   7.   The exhaust ventilation shall not be recirculated within the room or building if the materials stored are capable of emitting hazardous vapors.
(Amend Coun. J. 9-14-21, p. 35949, Art. V, § 5)