Rule 6: Safe speed

Here’s rule 6:

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 other vessels;
(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 hazards;
(vi)the draught in relation to the available depth of water.

(b) Additionally, by vessels with operational radar:

(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 of interference;
(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

Keep an eye on your log!

This rule basically states you need to make your own judgement on the appropriate speed for your vessel taking into account your surroundings and the situation you are in.

Both Rule 5: Look-out and Rule 6: Safe speed are closely linked. If you do not comply with rule 5, then you won’t be able to comply with rule 6.

Generally speaking a safe speed is a reduced speed. This is because in most circumstances if a vessel reduced speed, it’s closest point of approach [otherwise referred to as CPA] will increase and as a result the risk of collision reduces.

In addition to increasing your CPA, it’ll give your significantly more time to think and act. Thinking and Acting time is important as a leaving yourself with little time to react can impair your risk assessment process or personal judgement.

Remember that moving slowly allows your to stop quicker. We always teach our students that if a collision does occur for whatever reason, it’s better to crash slowly than quickly which will result in less damage.

You are responsible for proceeding at a safe speed. If an alteration of speed is necessary to avoid a collision or immediate danger then permission is not required.

Always monitor your speed and the situation around you. Always cross check your data and act early! Never rely on one instrument or on one technique. Maintaining a high speed due to commercial pressure is not an excuse and certainly not a defence if you are prosecuted for performing an unsafe act.

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Rule 6: safe speed
Rule 6: safe speed
Rule 6: safe speed
Rule 6: safe speed
Rule 6: safe speed
Rule 6: safe speed


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