Technical Booklet P Sanitary Appliances Unvented Hot Water Storage and Scalding·Page 15·2.17
Acceptable discharge arrangements
Discharge must be directed below a louvred grating in a trapped gulley or downward at low level with suitable guarding; grouped pipes must be marked for identification.
Acceptable discharge arrangements include –
(a) below a fixed louvred grating and above the water seal in a trapped gulley (see Diagram 2.1); or
(b) downward discharge at low level but no less than 100 mm above external surfaces and having a wire cage or suitable guard to prevent contact.
Where a number of discharge pipes are grouped together each discharge pipe should be marked to make the system which is discharging readily identifiable.
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