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Work out your safe speed, reaction time in fog
Divide the visibility by your speed and that is how long you have before you reach an obstacle that has only just come into sight.
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With five hundred metres of visibility and eight knots you have a good two minutes. That sounds like a lot, but it is not: spotting, assessing, deciding and manoeuvring all take time, and the other vessel may be making way too. This is why the collision regulations require a safe speed, one that allows you to stop within the distance you can see.
A collision in fog at a speed not suited to the conditions is the classic case in which the question of gross negligence is raised. Radar and AIS do not relieve you of that duty; they are no substitute for a proper lookout.
The waiver of the defence of gross negligence applies from Basis-Plus upwards, up to twenty-five per cent of the sum insured, and in Premium up to fifty per cent. It is a safeguard, not a free pass.
Frequently asked questions
What speed is appropriate in fog?
One that allows you to stop within half the distance you can see.
Will the insurer pay after a collision in fog?
Yes, under the waiver of the defence of gross negligence, from Basis-Plus up to twenty-five per cent and in Premium up to fifty per cent.
Worked out for your type of boat
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