T E C H N I C A L A N D I N S T A L L A T I O N
17
1. Plastic pipes should be joined and assembled with fittings appropriate to the circumstances in which
they are used as set out in BS EN ISO 1043-1.
2. Where pipes cannot be connected to the stack it may be possible to route a dedicated pipe alongside or
in close proximity to the discharge stack.
Termination of discharge pipe
3.61 The discharge pipe (D2) from the tundish should terminate in a safe place where there is no risk to
persons in the vicinity of the discharge.
3.62 Examples of acceptable discharge arrangements are:
(b) to a trapped gully with the end of the pipe below a fixed grating and above the water seal;
(c) downward discharges at low level; i.e. up to 100mm above external surfaces such as car parks, hard
standings, grassed areas etc. are acceptable providing that a wire cage or similar guard is positioned to
prevent contact, whilst maintaining visibility; and
(d) discharges at high level: e.g. into a metal hopper and metal downpipe with the end of the discharge
pipe clearly visible or onto a roof capable of withstanding high temperature discharges of water and 3m
from any plastic guttering system that would collect such discharges.
3.63 The discharge would consist of high temperature water and steam. Asphalt, roofing felt and non-
metallic rainwater goods may be damaged by such discharges.
Extract from ‘The Building Regulations 1991 G3’
Diagram: Typical discharge pipe arrangement
