18-29-425.3.1 Ball cocks.

   All flush tanks shall be equipped with an antisiphon ball cock conforming to ASSE 1002 or CSA CAN/CSA B125. The ball cock backflow preventer shall be located at least 1 inch (25 mm) above the full opening of the overflow pipe. A sheathed ball cock shall be installed in all gravity flush tanks in which the flush valve seat is located less than 1 inch (25 mm) above the flood level rim of the bowl.

18-29-425.3.2 Overflows in flush tanks.

   Flush tanks shall be provided with overflows discharging to the water closet or urinal connected thereto and shall be sized to prevent flooding the tank at the maximum rate at which the tanks are supplied with water. The opening of the overflow pipe shall be located above the flood level rim of the water closet or urinal or above a secondary overflow in the flush tank.

18-29-425.3.3 Sheet copper.

   Sheet copper utilized for flush tank linings shall conform to ASTM B152 and shall not weigh less than 10 ounces per square foot (0.03 kg/m 2 ).

18-29-425.3.4 Access required.

   All parts in a flush tank shall be accessible for repair and replacement.

18-29-425.4 Flush pipes and fittings.

   Flush pipes and fittings shall be of nonferrous material and shall conform to ASME A112.19.5 or CSA CAN/CSA B125.

18-29-426 Floor Sinks.