8.11.3 Operation of the valves
a) Where valves are required to have positive means of
closing, such means is to be readily accessible and provided
with an indicator showing whether the valve is
open or closed.
b) Where plastic pipes are used for sanitary discharges and
scuppers, the valve at the shell is to be operated from
outside the space in which the valve is located.
Where such plastic pipes are located below the summer
waterline (timber summer load waterline), the valve is to
be operated from a position above the freeboard deck.
Refer also to Ch 1, App 3.