9
The discharge pipework from the tundish:
Must fall continuously through its length.
Must be of a heat resistant material, e.g. metal.
Must not be fitted with any valves or taps.
Must discharge to a safe visible position, e.g. onto the surface of an external wall or into a gulley.
Must have a minimum of 300 mm straight pipework directly from the tundish.
Note: Where children may play or otherwise come into contact with discharges, a wire
cage or similar guard must be positioned to prevent contact whilst maintaining visibility.
The diagrams on this page show recommended methods of routing and terminating the discharge
pipe safely. Where a single pipe serves a number of discharges, such as in blocks of flats, the num-
ber served should be limited to not more than 6 systems so that any tundish installation can be
traced easily.
If a single common discharge pipe is used then it should be at least one pipe size larger than the
largest individual discharge pipe to be connected. If the system is installed where discharges from
safety devices may not be apparent, i.e. in dwellings occupied by blind, infirm or disabled people,
consideration should be given to the installation of an electronically operated device to warn when
discharge takes place.
Figure 4 - Discharge Pipe routing
Figure 5 - Tundish installation
5.2 High Level Termination of Discharge
At high level, discharge onto a roof is acceptable providing the roof is capable of withstanding high
temperatures and there is a distance of 3 m from any plastic guttering systems that would collect
such discharge.
Note:
The discharge may consist of scalding water and steam. Asphalt, roofing felt and non-metallic
materials may be damaged by such discharges.
Tundish
D1
D2
300mm
minimum
Tundish
300mm
minimum
D1
D2
Pipe close to wall to
allow water to fan out
safely
100mm max.
70mm min.
Ground level
Gulley if
available
Tundish
300mm
minimum
D1
D2
Type ‘A’
Air Gap
End of pipe
clearly visible
Option A
Option B
Option C
