12 Va. Admin. Code § 5-460-220
When not prescribed by the Virginia Uniform Statewide Building Code (13VAC5-63) in effect at the time of the pool's construction, the recirculation system shall be equipped with a rate of flow indicator reading in gallons per minute. Indicators shall be properly maintained, easily readable, and located so as to indicate both the rate of flow of the effluent from the filter and the rate of backwash in gallons per minute in sand or anthracite coal filters.
§ 35.1-11 of the Code of Virginia.
Derived from VR355-35-05 § 3, eff. March 1, 1962; amended, Virginia Register Volume 36, Issue 1, eff. October 17, 2019.