7.7.1.1.General (See Note A-7.7.1.1.)

(1) Non-potable water systems shall be designed, fabricated and installed in accordance with this Subsection and good engineering practice. (See Note A-7.7.1.1.(1)) (2) Except as provided in Sentence (3) and Subsection 7.7.2., non-potable water systems shall only be used to supply water closets, urinals, trap seal primers, and directly connected underground irrigation systems that only dispense water below the surface of the ground. (3) Non-potable water systems shall not be used to supply fixtures in healthcare facilities. (4) Where a non-potable water system is supplied by a potable water system, the potable water system shall be protected in accordance with Article 7.6.2.1. (5) Where the static pressure at any fixture in a non-potable water system may exceed 550 kPa, a pressure-reducing valve shall be installed to limit the maximum static pressure at the fixture to 550 kPa. (6) Where a clothes washer is supplied by a rainwater system and a potable water system, the potable water system shall be protected by dual check valve backflow preventers conforming to CSA B64.6, “Dual check valve (DuC) backflow preventers” for (a) area isolation, and (b) premise isolation.