Ariz. Admin. Code § R18-5-234 - Disinfection

A. An adjustable automatic chemical feeder shall be provided to ensure the continuous disinfection of the water in a public or semipublic swimming pool or spa. Timers on disinfection equipment are prohibited. Disinfection shall be accomplished by chlorination or by another method that is approved by the Department. The method of disinfection shall effectively maintain an adequate disinfectant residual in the water which is subject to field testing by methods that are easy to use and accurate.

1. Chlorine disinfection equipment for a public or semipublic swimming pool shall be designed to maintain a free chlorine residual of 1.0 to 3.0 ppm. Chlorine disinfection equipment for a public or semipublic spa shall be designed to maintain a free chlorine residual of 3.0 to 5.0 ppm.

2. Bromine disinfection equipment for a public or semipublic swimming pool shall be designed to maintain a bromine residual of 2.0 to 4.0 ppm. Bromine disinfection equipment for a public or semipublic spa shall be designed to maintain a bromine residual of 3.0 to 5.0 ppm.

B. The use of chlorinated isocyanurates or cyanuric acid stabilizer for disinfection and stabilization is permitted. If used, chlorinated isocyanurates shall be fed so as to maintain required disinfectant residual levels. Cyanuric acid levels, whether from chlorinated isocyanurates or from the separate addition of cyanuric acid stabilizer, shall not exceed 150 ppm.

C. The use of chloramines as a primary disinfectant of swimming pool or spa water is prohibited.

D. The addition of gaseous disinfectant directly into a public or semipublic swimming pool is prohibited. The addition of dry or liquid disinfectant directly into a public or semipublic swimming pool or spa for routine disinfection is prohibited. This prohibition does not prohibit the use of liquid or dry disinfectants for shock treatment of a swimming pool or spa. A chlorine gas disinfection system shall not be used for the disinfection of water in a public or semipublic spa.

E. A common chlorine gas disinfection system may be utilized in separate swimming pools if separate metering and feeding devices are provided for each swimming pool.

F. If gaseous chlorine is used for disinfection, the following shall be provided:

1. The chlorinator, chlorine cylinders, and associated chlorination equipment shall be located in a separate well ventilated enclosure at or above ground level. The enclosure shall be reasonably gas-tight, noncombustible, and corrosion-resistant. The door of the enclosure shall open to the outside and shall not open directly toward the swimming pool.

2. If chlorination equipment is placed in a room, then an exhaust fan or gravity ventilation system shall be provided. Mechanical exhausters shall take suction 6 inches or less above the floor and discharge through corrosion-resistant louvers to a safe outside location. A gravity ventilation system shall be designed and constructed to discharge to the outside from floor level. Fresh air intakes shall be located no closer than 3 feet above the ventilation discharge. Chlorine room exhausts shall be directed away from the swimming pool to an area which is normally unoccupied. Chlorine room fans shall be capable of completely changing the air in the room at least once a minute.

3. Electrical switches to control lighting and ventilation in the chlorine room shall be located on the outside of the enclosure and adjacent to the door.

4. Chlorine cylinders shall be kept in an upright position and securely anchored to prevent them from falling. Chlorine cylinders may be stored indoors or out. If stored outside, chlorine cylinders shall not be stored in direct sunlight. Chlorine cylinders shall not be stored near an elevator, ventilation system, or heat source.

5. A warning sign shall be placed on the outside of the door to the chlorine room which cautions persons of the danger of chlorine gas within the enclosure. The warning shall be in letters 3 inches high or larger. The door to the chlorine room shall be provided with a shatter resistant inspection window.

6. Chlorinators shall be a solution-feed type, capable of delivering chlorine at its maximum rate without releasing chlorine gas to the atmosphere. Chlorinators shall be designed to prevent the backflow of water into the chlorine solution container.

G. Granular, tablet, stick, and other forms of dry disinfectant shall be fed by an adjustable automatic feeding device.

H. Disinfection equipment and chemical feeders shall comply with the requirements set forth in American National Standard/NSF International Standard 50, "Circulation System Components and Related Materials for Swimming Pools, Spas/Hot Tubs," NSF International, 3475 Plymouth Road, P.O. Box 130140, Ann Arbor, Michigan [revised July, 1996, and no future editions] which is incorporated by reference and on file with the Office of the Secretary of State and the Department.

I. If a chemical feeder is used, it shall be installed to inject solution downstream from the filter and the heater. An erosion-type feeder may be installed to feed solution to the suction side of the pump. A chemical feeder shall be wired so it cannot operate unless the filter pump is running.

Notes

Ariz. Admin. Code § R18-5-234

Adopted effective February 19, 1998 (Supp. 98-1).