It is considered that a freeing port area, in the lower
part of the bulwarks, of 33% of the total area of the bulwarks provides
the "other effective freeing arrangements" mentioned in regulation 26(5), and may be considered equivalent
to the 50% open rails in way of trunks required by regulation
36(1)(e).
Regulation 27(7): Freeing
arrangements on ships having reduced B freeboard assigned and fitted
with bulwarks on the freeboard deck
For Type 'B' ships with freeboards reduced by not more than
60% of the difference between B and A tables there shall be freeing
port area in the lower part of the bulwarks equal to at least 25%
of the total area of the bulwarks.
The upper edge of the sheer strake shall be kept as low
as possible.