Historical
IGC 91-2004a
INTERIM GUIDE CRITERIA FOR ELECTRICAL ANTI-SCALE WATER CONDITIONING APPLIANCE
This standard covers electrical anti-scale water conditioning appliances in nominal pipe sizes from 1/2 in. (12.7 mm) through 3 in. (76.2 mm) and configurations include male nominal pipe threads (MNPT) for plastic and metal fittings and female nominal pipe threads (FNPT) for metal fittings only. In nominal pipe sizes from 3 in. to 16 in., flanged connections shall be used with the anode and cathode isolated from each other. This standard covers definitions, general requirements, in addition to general description of materials used and the method of marking and identification. It is not the intent of this standard to rate or verify the effectiveness of these products in reducing or eliminating scale in water piping systems. The effectiveness of these fittings or appliances is beyond the scope of this standard.
International Association of Plumbing and Mechanical Officials [iapmo]