Marine Order 32 (Cargo handling equipment) 2016

there must be a clear space of 760 mm by 760 mm in front of each rung of a vertical ladder with no obstructions intruding into the space;

however, the space may be reduced to 600 mm by 600 mm in a trunked accessway;

any obstruction (such as stiffeners or deck plates protruding into the clear space) reducing clearance to less than 650 mm from the ladder to the opposite wall must be plated over or otherwise protected;

a lamp fitting in a trunked accessway must be sited in corners only, with minimum possible projection;

the clearance behind the ladder must be at least 150 mm from the centre of the tread or the rung;

there must be at least 75 mm for hand clearance on each side of the ladder and around vertical hand grips;

access space in front of the rungs of an inclined ladder must be at least 1850 mm measured vertically above the centre of each step;

there must be a gap of 35 mm behind the tread to minimise build up of material that may impair the foothold.