International regulations for
preventing collisions at sea (1972)
Rules in this section apply in any condition
Every vessel shall at all times maintain a
proper look-out by sight and hearing as well as by all available means
appropriate in the prevailing circumstances and conditions so as to make a full
appraisal of the situation and of the risk of collision.
Every vessel shall at all times proceed at a
safe speed so that she can take proper and effective action to avoid collision
and be stopped within a distance appropriate to the prevailing circumstances and
conditions. In determining a safe speed the following factors shall be among
those taken into account:
(a) By all vessels:
(i) the state of visibility.
(ii) the traffic density including concentrations of fishing vessels or any
(iii) the manoeuvrability of the vessel with special reference to stopping
distance and turning ability in the prevailing conditions;
(iv) at night the presence of background light such as from shore lights or from
back scatter of her own lights;
(v) the state of wind, sea and current, and the proximity of navigational
(vi) the draught in relation to the available depth of water.
(b) Additionally, by vessels with operational
(i) the characteristics, efficiency and
limitations of the radar equipment;
(ii) any constraints imposed by the radar range scale in use;
(iii) the effect on radar detection of the sea state, weather and other sources
(iv) the possibility that small vessels, ice and other floating objects may not
be detected by radar at an adequate range;
(v) the number, location and movement of vessels detected by radar;
(vi) the more exact assessment of the visibility that may be possible when radar
is used to determine the range of vessels or other objects in the vicinity.