(1) An access openings in bulkheads of enclosed
superstructures and other outer structures through which water could
enter and endanger the vessel, shall be fitted with doors permanently
attached to the bulkhead, framed and stiffened so that the whole structure
is of equivalent strength to the unpierced structure, and weathertight
when closed. The means for securing these doors weathertight shall
consist of gaskets and clamping devices or other equivalent means
and shall be permanently attached to the bulkhead or to the doors
themselves, and shall be so arranged that they can be operated from
each side of the bulkhead. The Administration may, without prejudice
to the safety of the crew, permit the doors to be opened from one
side only for freezer rooms, provided that a suitable alarm device
is fitted to prevent persons being trapped in those rooms.
(2) The height above deck of sills in those doorways,
in companionways, erections and machinery casings which give direct
access to parts of the deck exposed to the weather and sea shall be
at least 600 mm on the working deck and at least 300 mm on the superstructure
deck. Where operating experience has shown justification and on approval
of the Administration, these heights, except in the doorways giving
direct access to machinery spaces, may be reduced to not less than
380 mm and 150 mm respectively.