(1) Except where flushing-valves are installed in accordance with the provisions of section 10, no person shall cause or permit any service-pipe to be connected, without the interposition of a storage tank fitted with a ball-valve, to any water-trough, water-closet, urinal, steam- or hot-water boiler, closed water-heater or container or apparatus in which any contaminant is mixed with water supplied by the local authority:

Provided that hot-water cylinders of the push-through type, incorporating approved non-return valves, shall be permitted with prior approval of the local authority.

(2) Every such water-trough, water-closet, urinal, steam- or hot-water boiler, closed water-heater, container or apparatus shall be fed separately and directly from such storage tank, which shall be installed solely for that purpose.

(3) No boiler, hydraulic machine or any apparatus liable to cause shock or vibration to any of the water-pipes shall take a direct supply from the water-main, but shall be supplied from an intermediate suitable storage tank with the supply controlled by a float-valve.