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6. Safe speed
Any vessel must proceed at a safe speed, which she can to take action to avoid collision and able to stop within the distance for the prevailing conditions (including the visibility, weather, traffic condition, background lights, her manoevrability (e.g. stopping distance and turning circles) and draft in relation with the available water).
When radar is in use, also consider if there is any limitations of the equipment, range scale in use, weather and other interference, weak targets, targets density and movement, and use radar to judge the visibility is much accurate for objects nearby.
7. Risk of Collision
Vessels must use all available means to determine the risk of a collision, including the use of radar (if available) to get early warning of the risk of collision by radar plotting or equivalent systematic observation of detected objects. (e.g. ARPA, AIS).
If the distance of any vessel is reduced and her compass bearing does not change much or a large vessel or towing vessel at close distance or if in doubt, risk of collision shall be deemed to exist.
8. Action to avoid collision
Actions taken to avoid collision should be:
positive
obvious
made in good time
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