1. If other regulations prohibit
(a) smoking;
(b) using fires and naked light;
on board, the prohibition shall be indicated by circular white boards bordered with red, with a red diagonal and a picture of a burning match or, alternatively, by circular white boards bordered with red, with a red diagonal and a picture of a cigarette emitting smoke.
The boards shall be placed on the vessel or on the gangway, as circumstances require. By derogation from article 3.03, they shall be about 60 cm in diameter.
2. By night, the boards shall be illuminated so as to be clearly visible on both sides of the vessel.