Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 7·86
Sanitary appliances - general requirements
Sanitary appliances must have smooth, non-absorbent surfaces and discharge through effective traps. Washbasins, baths and showers must have hot and cold water supply with cold water starting first on sequential mixer valves. Water closets and urinals must have effective flushing apparatus with no direct connections outside flush pipes or sanitary pipework.
Every sanitary appliance shall have smooth and readily cleansed, non-absorbent surfaces and shall discharge through an effective trap of suitable dimensions. Every washbasin, bath and shower shall have provision for the piped supply of hot and cold water and where a sequential single control mixer valve is provided it shall start from the cold supply. Every water closet and urinal shall have flushing apparatus capable of effectively cleansing the receptacle, no part of which shall be directly connected to any pipe other than a flush pipe or sanitary pipework. The outlet of an urinal shall have an effective grating. A sanitary appliance fitted with a macerator, pump and drainage pipe shall ensure the hygienic conveyance of foul water to an underground foul drainage system.
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