37. Manholes.

(a) for depth of 0.8 m. or less
0.75 x 0. 75 m.
(b) for depths between 0.8 m. and 2.1 m.
.. 1.2 x 0.9 m.
(c) for depths more than 2.1 m.
rectangular chamber with minimum internal dimensions of 1.1 x
0.9 m.