(1) A pool shall have around the perimeter an overflow gutter or automatic skimming devices, (hereinafter referred to as skimmers), or such other devices as may be approved by the medical officer of health.
(2) Where overflow gutters are used, they shall be built into the wall extending around the pool except where steps require interruption, and the gutter shall be not less than 3 inches deep; the overflow edge shall be round and shall not exceed to a thickness or 2½ inches for the top 2 inches.
(3) Skimmers may be used as an overflow device on pools with a surface not exceeding 4000 square feet and shall comply with the following requirements—
(a) they shall be built into a recess in the wall of the pool;
(b) the rate of flow through the skimmer shall be adjustable up to at least 50% of the capacity of the recirculating systems of the swimming pool;
(c) the skimmer shall be provided with a device to prevent air lock in the recirculation system of the suction line;
(d) they shall be provided with a screen which is capable of being easily removed and cleaned to trap large solids.