(A) The type of protection required under § 51.122(A), (B) and (C) of these regulations shall depend on the degree of hazard which exists, as follows:
(1) An approved fixed proper air gap separation shall be installed where the public water supply system may be contaminated with substances that could cause a severe health hazard;
(2) An approved fixed proper air gap separation or an approved reduced pressure principle backflow prevention device shall be installed where the public water supply system may be contaminated with a substance that could cause a system or health hazard; and
(3) An approved fixed proper air gap separation, approved reduced pressure principle backflow prevention device or a double check valve assembly shall be installed where the public water supply system may be polluted with substances that could cause a pollution hazard not dangerous to health.
(B) The type of protection required under § 51.122(D) shall be an approved fixed proper air gap separation or an approved reduced principle backflow prevention device, or:
(1) The type of protection required under § 51.122(D) shall be an approved double detector check valve assembly prevention device; or
(2) Where a public water supply or an auxiliary water supply is used for a fire protection system, reduced pressure principle backflow preventers shall be installed on fire sprinkler systems connected to the public water supply when:
(a) The sprinkler system contains antifreeze, fire retardant or other chemicals;
(b) Water is pumped and/or flows by gravity into the fire safety system from a nonpotable source capable of serving the fire system. A nonpotable source of water shall be considered capable of serving the fire safety system under the following conditions: it must be capable of year-round use, maintained with not less than 50,000 gallons of usable water not subject to freezing, accessible to firefighting pumper equipment, located within 1,700 feet of the facility; or
(c) There is a permanent or emergency connection whereby water can be pumped into the fire safety system from any other nonpotable source, such as a river, lake, lagoon, retention pond or swimming pool.
(C) An approved double detector check valve assembly backflow prevention device shall be installed on all existing fire sprinkler systems whenever physical space for installation of the device is available except as provided under division (B)(2) of this section, or:
(1) When physical space is not available, existing fire sprinkler systems which include a single check valve shall be retrofitted by installing a weighted detector check and an alarm valve approved under UL Standard 193 with alarm accessories approved under UL Standard 753. The weighted detector check shall consist of a single check with a weighted clapper. Alarm valves shall be equipped with a connection to transmit a signal to a remote monitoring station which is an approved fire alarm receipt point.
(2) Sprinkler alarms installed in accordance with this section shall be installed so that any flow of water in either direction from a sprinkler system which is equal to or greater than the flow from a single automatic sprinkler of the smallest orifice size installed on the system will result in an audible alarm on the premises and transmission of a signal to an approved fire alarm receipt point, being the City Public Safety Building. Installation of sprinkler alarm systems shall be in accordance with NFPA 13 (§ 3-17), Installation of Sprinkler Systems; NFPA 71, Standard for the Installation, Maintenance and Use of Signaling Systems for Central Station Service; NFPA 72B, Standard for Auxiliary Protective Signaling Systems; NFPA 72C Standard for Remote Station Protective Signaling Systems; or NFPA 72D, Standard for Proprietary Protective Signaling Systems.
(3) When an existing fire safety system is expanded to the extent that an additional riser is required, the entire system must be brought into compliance with existing regulations and equipped with a backflow protection device according to division (B)(1) of this section.
(1990 Code, § 30-314) (Ord. 90-1332, passed 2-19-1990; Ord. 91-1386, passed 2-18-1991)