N.Y. Comp. Codes R. & Regs. tit. 10, § 14-1.175 – Ventilation.

(a) All rooms are to be provided with sufficient ventilation to keep them free of excessive heat, steam, condensation, vapors, odors, smoke and fumes. Ventilation systems, when vented to the outside, are not to create an unsightly or harmful discharge or create a nuisance.
1. (1) Intake and exhaust air ducts are to be constructed and maintained to prevent the entrance of dust, dirt or other contaminating materials into the establishment.
2. (2) In new or extensively remodeled establishments, mechanical ventilation is required in all rooms where odors, vapors or fumes originate.
(b) Ventilation hoods and devices are to be constructed and installed to prevent grease or condensation from collecting on walls or ceilings and from dripping into food or onto food-contact surfaces.