Division .5.3 F1
United Kingdom
The means of operation whether by power or by hand of any sliding watertight door whether power-operated or not shall be capable of closing the door with the ship listed to 15 ° either way. Consideration shall also be given to the forces which may act on either side of the doors as may be experienced when water is flowing through the opening applying a static head equivalent to a water height of at least 1 metre above the sill on the centreline of the door.