N.Y.C. Admin. Code § 27-521: § 27-521 Ventilation.

Mechanical ventilation systems for storage vaults shall be adequate to effect ten complete air changes per hr. Exhaust shall be taken from within twelve inches above the level of the top of the dike. The exhaust system shall be independent of exhaust systems serving other parts of the building and the openings to the outdoors shall be located in accordance with the provisions of subchapter thirteen of this chapter for system conveying vapors.