Ariz. Admin. Code § R18-5-230 - Flow Meter
A public swimming pool shall be equipped with, a flow meter which indicates the rate of backwash through the filter. The flow meter shall be installed between the pump and the filter on a straight section of pipe in accordance with the manufacturer's specifications in a location where it can be read easily. The flow meter shall measure the rate of flow through the filter in gallons per minute and shall be accurate to within 5% under all conditions of flow. The flow meter shall have an indicator with a range of at least 150% of the normal flow rate.
Notes
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