20. Sewage storage tank
(1) Where a temporary toilet is connected to a sewage storage tank, the tank is to be constructed and equipped in accordance with this regulation.
(2) A sewage storage tank is to be moulded in one piece from material which is ¾
(a) impact and corrosion resistant;
(b) impervious; and
(c) finished to provide a smooth surface both internally and externally.
(3) A sewage storage tank is to be constructed so that it does not leak.
(4) A sewage storage tank is to have a minimum useable capacity of 200 l.
(5) A sewage storage tank is to be vented through the roof of the unit by a vent pipe that ¾
(a) has a minimum diameter of 40 mm; and
(b) is fitted with a cowl.
(6) A sewage storage tank is to be fitted with a draw off point for the emptying of the tank.
(7) Where the draw off point for a sewage storage tank is situated externally ¾
(a) it is to be fitted with a device to enable emptying of the tank without causing spillage; and
(b) it is to be capable of being secured so that it cannot be tampered with or opened by a person who is not authorised to do so.