2 Va. Admin. Code § 5-150-160
Potable water shall be offered at least every four hours after initiation of travel, except that vehicles which are environmentally controlled to maintain temperatures between 45°F and 85°F at all times shall offer water at least every 12 hours.
§ 3.2-6501 of the Code of Virginia.
Derived from VR115-02-13 § 3.5, eff. May 13, 1987.