Technical Booklet N Drainage·Page 7·80
Sanitary pipework requirements
Sanitary pipework must be properly sized, constructed, and watertight to convey foul water hygienically, with sufficient ventilation and means of access for blockage clearance.
Sanitary pipework shall—
(a) consist of pipes and fittings—
(i) of such size, layout, construction and watertightness; and
(ii) with sufficient ventilation,
to ensure the hygienic conveyance of foul water to an underground foul drainage system; and
(b) have such means of access as is necessary to facilitate the clearance of blockages.
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