Ariz. Admin. Code § R18-5-227 - Filters

A. Filters shall be designed, located, and constructed to permit removal of filter manhole covers or heads for inspection, replacement, or repair of filter elements or filter media. No filtration system shall be installed beneath the surface of the ground or within an enclosure without providing adequate access for inspection and maintenance.

B. Pressure-type filters shall be equipped with a means to release internal pressure. Each pressure filter shall be equipped with an air relief piping system connected at an accessible point near the crown. Automatic air relief systems may be used instead of manual systems. The design of a filter with an automatic air relief system as its principal means of air release shall include lids that provide a slow and safe release of pressure. The design of a separation tank used in conjunction with any filter tank shall include a manual means of air release or a lid which provides a slow and safe release of pressure as it is opened.

C. Pressure filter systems shall be equipped with a sight glass installed on the waste discharge pipe.

D. Swimming pool and spa filters shall comply with American National Standard/NSF International Standard Number 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.

E. The maximum filtration rate shall not exceed the design flow rate prescribed by the National Sanitation Foundation Standard 50 for commercial filters. In no case shall the maximum filtration rate exceed the following:

1. The rate of filtration in a high-rate sand filter shall not exceed 25 gallons/minute/square foot.

2. The rate of filtration of a diatomaceous earth filter shall not exceed 2 gallons/minute/square foot.

3. The rate of filtration of a cartridge filter shall not exceed 0.375 gallons/minute/square foot.

Notes

Ariz. Admin. Code § R18-5-227

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