ABSTRACT
Peak flow Pipe size Minimum Maximum l/s mm gradient capacity
l/s
< 1 75 1 : 40 4.1 < 1 100 1 : 40 9.2 > 1 75 1 : 80 2.8 > 1 100 1 : 80 * 6.3 > 1 150 1 : 150 † 15.0
Pipe Ø Gradient Pipe Ø Gradient
50 1 : 500 150 1 : 2160 75 1 : 860 175 1 : 2680
100 1 : 1260 200 1 : 3200 125 1 : 1680 225 1 : 3720
* Minimum of 1 WC † Minimum of 5 WCs
Traps minimum sizes and seal depths Appliance Ø trap Seal depth Ø trap Seal depth
mm mm mm mm
washbasin 32 75 waste disposer 40 75 bidet 32 75 urinal 40 75 bath* 40 50 sink 40 75 shower* 40 50 washing machine* 40 75 syphonic WC 75 50 dishwasher* 40 75
*Where these fittings discharge directly into a gully the seal depth may be reduced to a minimum of 38 mm.
