A. For Cross-Connection control, fire protection systems may be classified on the basis of water source and arrangement of supplies as follows:
1. Class 1 - Direct connections from public water mains only; no pumps, tanks or reservoirs; no physical connection from other water supplies; no antifreeze or other additives of any kind; all sprinkler drains discharging to atmosphere, dry wells, or other safe outlets.
2. Class 2 - Same as Class 1, except that booster pumps may be installed in the connections from the street water mains. (Booster pumps do not affect the potability of the system, but it is necessary to avoid drafting so much water that pressure in the water main is reduced below ten (10) psi.)
3. Class 3 - Direct connection from public water main plus one or more of the following: elevated storage tanks; fire pumps
taking suction from above-ground covered reservoirs or tanks; and pressure tanks. (All storage facilities are filled or connected to public water only, the water in the tanks to be maintained in a potable condition. Otherwise, Class 3 systems are the same as Class 1.)
4. Class 4 - Directly supplied from public water mains similar to Classes 1 and 2, and with an auxiliary water supply on or available to the Premises; or an auxiliary supply may be located within seventeen hundred feet (1,700') of the pumper connection.
5. Class 5 - Directly supplied from public water mains, and interconnected with auxiliary supplies, such as: pumps taking suction from reservoirs exposed to Contamination, or rivers and ponds; driven wells; mills or other industrial water systems; or where antifreeze or other additives are used.
6. Class 6 - Combined industrial and fire protection systems supplied from the public water mains only, with or without gravity storage or pump suction tanks.
B. Class 1, 2 and 3 fire protection systems will normally require minimum protection (approved double-check valves) to prevent stagnant waters from back-flowing into the public potable water system. Class 4 systems will normally require Backflow prevention at the Service Connection. The type (air gap, reduced-pressure, or double check valves) will generally depend on the quality of the auxiliary supply. Classes 4 and 5 systems normally need maximum protection (air gap or reduced pressure) to protect the public potable water system. Class 6 system protection depends on the requirements of both industry and fire protection, and can only be determined by a survey of the Premises.
C. A meter (compound, detector check) is not normally permitted as part of a Backflow Prevention Device. Exceptions may be made if the meters and Backflow Prevention Devices are specifically designed for that purpose.
D. All "Anti-Freeze" fire protection systems shall have a "Reduced Pressure Principal Backflow Prevention Device" in the system. The manufacturer shall be as approved by the OEPA.