21.10.1 Adequate sanitary toilet facilities should
be provided on board. The facilities should be at least one water
closet, one shower for every 8 persons or part thereof, and one washbasin
for every 6 persons or part thereof.
21.10.2 In vessels where a sanitary system, including
a holding tank, is provided, care should be taken to ensure that there
is no possibility of fumes from the tank finding their way back to
a toilet, should the water seal at the toilet be broken.