Technical Booklet N Drainage·Page 26·3.13
Siting of access points for drains
Access points must be provided at specified locations along drain runs, including at the head of drains, at bends, changes of gradient or pipe size, junctions, at regular intervals on long runs, and near connections to sewers.
An access point should be provided at the following –
(a) at or near the head of each length of drain;
(b) at a bend;
(c) at a change of gradient;
(d) at a change of pipe size;
(e) at a junction;
(f) on long lengths of drain at not greater than the distance given in Table 3.5; and
(g) within 12 m of the connection to a sewer unless access is provided at the connection.
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