Section: Safety and Security
Policy Number: 7-30
Policy Name: Protection of Potable Water Supply
Date: August 29, 1988
Revisions: April 1, 1996; January 12, 2006

  1. PURPOSE

    To ensure potable water supply systems are designed, installed, maintained and utilized in such a manner as to prevent contamination from nonpotable liquids, solids or gases.

  2. POLICY

    1. General

      Potable water supply system shall be designed, installed and maintained in such a manner as to prevent contamination from nonpotable liquids, solids or gases being introduced into the potable water supply through cross-connections or any other piping connections to the system. The Facilities Planning and Construction Department shall ensure new facilities and renovations comply with the requirements of The IBC Plumbing Code or the latest plumbing code adopted by the City of Newark. The Facilities Management Department shall ensure facilities are maintained in accordance with this code.

    2. Toxic Materials

      1. Toxic materials shall be kept out of the potable water system.

      2. Chemicals or other substances that could produce either toxic conditions, taste, odor or discoloration in the potable water system shall not be introduced into, or used in such systems.

      3. Piping which has been used for any purpose other than conveying potable water shall not be used for conveying potable water.

      4. Water used for the cooling of equipment or other processes shall not be returned to the potable water system. Such water shall be discharged into a drainage system through an air gap, or may be used for nonpotable purposes.

    3. Backflow Protection

      All potable water openings and outlets shall be protected against backflow by one of the following:

      1. Protection by air gap.

      2. Protection by atmospheric type vacuum breaker.

      3. Protection by reduced pressure principle backflow preventer.

      4. Protection by barometric loop.

    4. Connections to the Potable Water System

      1. Boilers: The potable water supply to a boiler shall be equipped with a check valve. When boilers have conditioning chemicals introduced into the system, the potable water connection shall be protected by an air gap or reduced pressure principle backflow preventer.

      2. Heat exchangers: Heat exchangers using an essentially toxic transfer fluid shall be separated from the potable water by a double wall construction. An air gap open to atmosphere shall be provided between the two walls. Heat exchangers using an essentially nontoxic transfer fluid may be of single wall construction.

        Exception: Heat exchangers using an essentially toxic transfer fluid with a pressure on the transfer fluid side a minimum of 10 psi lower than the pressure on the potable water side protected with a pressure gradient monitor may be of single wall construction.

      3. Connections to automatic fire sprinkler systems: The potable water supply to automatic fire sprinkler systems and standpipes shall be equipped with a check valve.

      4. Connections subject to back pressure: When a potable water connection is made to a nonpotable line, fixture, tank, vat, pump or other equipment subject to back pressure, the potable water connection shall be protected by a reduced pressure principle backflow preventer.

    5. Laboratory Equipment and Processes

      1. Laboratory personnel shall not remove backflow prevention devices from building potable water systems.

      2. Laboratory personnel shall assure that each potable water connection to a piece of equipment is protected by an atmospheric type vacuum breaker unless otherwise approved by the Department of Environmental Health and Safety.

      3. Each piece of equipment connected to a potable water system that incorporates a water pump shall be protected by a reduced pressure backflow preventer.

      4. Whenever potable water is discharged into a tank, vat, sink or other container, the potable water system shall be protected. For air gaps, the minimum required air gap measured vertically from the lowest end of a potable water outlet to the flood level rim of the fixture or receptacle into which it discharges shall be at least 3 inches.

      5. A hose conveying process water from laboratory equipment for discharge into the sewage system shall incorporate backflow prevention. For air gaps, the minimum required air gap measured vertically from the lowest end of the discharge water outlet to the flood level rim of the fixture or receptacle into which it discharges shall be at least 3 inches.

      6. Whenever laboratory equipment is connected to more than one utility (cold water, hot water, steam, etc.), each utility line shall be protected with a backflow preventer.

    6. Administration

      1. Unit administrators shall ensure overall compliance with this policy and ensure violations are corrected.

      2. Unit administrators shall ensure the provisions of this policy are communicated to employees and students.

      3. Laboratory supervisors and faculty shall ensure all laboratory equipment and processes are operated in compliance with this policy.

      4. Individuals or Safety Committees conducting laboratory inspections shall inspect for compliance with this policy.

      5. Removing or tampering with building backflow preventers shall be a violation of Policy 2- 17, "Facility Systems".

For more information regarding this policy and backflow prevention contact the Facilities Management Department or the Department of Environmental Health and Safety.