N.Y. Comp. Codes R. & Regs. Tit. 10 §§ 14-5.140
Plumbing is to be sized, installed and maintained to carry potable water to all parts of the food vending operation in quantities and at pressures needed for satisfactory operation. Sewage and liquid wastes are to be handled and disposed of in a manner which protects the premises, personnel and contents within the establishment and surroundings from contamination. All plumbing is to be constructed and maintained to prevent contamination of the potable water supply, food, equipment, utensils, the premises, contents, employees and patrons. There is to be no direct connection between the sewage system and any drains originating from fixtures and equipment used for storage, preparation or processing of food or drink. Waste lines from equipment requiring indirect drains are to be installed so as to prevent backflow from sewers and drains from other fixtures.
N.Y. Comp. Codes R. & Regs. Tit. 10 §§ 14-5.140