Hong Kong Regulations

BUILDING (STANDARDS OF SANITARY FITMENTS, PLUMBING, DRAINAGE WORKS AND LATRINES) REGULATIONS - REGULATION 24

Traps for soil fitments

(1) Every soil fitment shall be provided with a suitable trap with a water
seal of not less than 50 mm.

(2) The internal diameter of every such trap shall be not less than-

   (a)  80 mm, in the case of a watercloset fitment, slop sink, or urinal with
        more than 3 basins or stalls or with a channel longer than 2 m;

   (b)  50 mm, in the case of a urinal with more than one and not more than 3
        basins or stalls or with a channel not longer than 2 m;

   (c)  40 mm, in the case of a bidet or urinal with a single basin or stall;
        and

   (d)  100 mm, in the case of a trough watercloset. (L.N. 294 of 1976)