NAC444.496. Filters.

     1. Filters must be designed to maintain spa water under anticipated operating conditions in accordance with NAC 444.484.

     2. Filters must be designed so that filtration surfaces can be easily restored to design capacity, inspected and serviced.

     3. Separate filter, recirculation and chlorination systems must be provided for each spa and must be independent of any adjacent swimming pool or spa.

     4. A means must be provided to permit release of air which enters the filter tank. This may be automatic, manual, or, when upflow design is used, air must be expelled through the filter tank. Any filters incorporating an automatic internal air release as the principal means of air release must have lids which provide a slow and safe release of pressure as a part of its design. Any separation tank used in conjunction with a filter tank must have, as part of its design, a manual means of air release or a lid which provides a slow and safe release of pressure as it is opened. Each separation tank must have a cautionary statement warning the user not to start up the filter pump without first opening the air release. The statement must be visible and noticeable within the area of the air release.

     5. Piping furnished with the filter must be of suitable material capable of withstanding three times the working pressure. The suction piping must not collapse when there is a complete shutoff of flow on the suction side of the pump.

     6. Filter components which require servicing must be accessible and available for inspection and repair when installed according to the manufacturer’s instructions.

     7. All filters must meet the applicable standards adopted by the National Sanitation Foundation.

     8. When the filter is regenerated by backwashing, provisions must be made to dispose of the backwash water in a sanitary manner and without undue labor.

     [Bd. of Health, Public Spa Reg. Art. 21, eff. 11-27-79]