Manual of Naval Preventive Medicine
Chapter 1: Food Service Sanitation
VIII: Structural Requirements and Sanitary Controls

1-61. Water Supply and Sewage Disposal.

Department of the Navy
Bureau of Medicine and Surgery

1. Potable Water System

a. Ashore, adequate potable water for the needs of the food service facility must be provided from an approved source and meet the standards of NAVMEDCOMINST 6240.1 and/or Chapter 5 of this publication. At sea potable water standards can be found in Chapter 6 of this manual and/or NSTM 533.

b. Hot and/or cold water under pressure must be provided to all fixtures and equipment that use potable water.

c. Plumbing, fixtures and equipment must be installed to preclude backflow into the potable water supply system (e.g., faucets on which hoses are attached must have a backflow prevention device). Other outlets must be protected by an air gap twice the effective opening of the potable water outlet diameter, unless the outlet is a distance less than three times the effective opening away from a wall or similar vertical surface, in which case the air gap must be three times the effective opening of the outlet. In no case will the air gap be less than 1 inch.

2. Steam used in contact with food and food-contact surfaces must be free from any materials or additives other than those specified in 21 CFR 173.310. Currently, shipboard steam contains additives which are not acceptable.

3. Ashore, all sewage wastes must be disposed of through an approved community sewage treatment plant or an individual sewage disposal system which is sized, constructed, maintained and operated according to law. References concerned with disposal at sea include Chapter 7 of this publication, OPNAVINST 5090.1, and NSTM 593.

4. Dishwashing machines, refrigerators, steam kettles potato peelers, ice making machines and other similar equipment must not be directly connected to the sewage system without an air device between the equipment and the wastewater lines. Where permitted by law, a sink may have a direct connection provided the drain line is properly trapped. Ware washing machines may have direct connections between their waste outlets and the floor drain when the connection is on the sewer side and immediately adjacent to the floor drain trap, and the drain line from the machine is properly trapped and vented.