Operation & Maintenance Manual
13 |
P a g e
6.
PIPEWORK, DUCTS AND SAMPLE CHAMBERS
6.1 Pipework
Gradient. It must be ensured that there is sufficient fall (gradient) from the dwelling to the invert level of
the inlet pipe, normally 0.5m below the top lip of the unit. A fall of between 1:50 and 1:100 is usually
required to give a self-scouring velocity that prevents blockages in the pipes.
6.2 Sample Chamber
Positioning. This should be close to the outlet from the plant to provide a point at which the Environment
Agency can take a sample.
Dimensions. The sample chamber should incorporate a large enough drop to allow a sample chamber to
be filled with the treated discharge. The following drawings give an indication of dimensions.
100 mm
200 mm
FROM
HIPAF
OUTLET
SIDE
PLAN
END