In the winter we usually have a few days of fog. So it is timely to review the rules covering vessels in restricted visibility. Some things seem obvious. Remember that safe speed is reduced as visibility is reduced. Maintain a proper lookout. Use radar if you have it, and display your navigation lights, even in the daytime.
If you hear a fog signal forward, reduce your speed to bare steerageway and navigate with extreme caution. Do not alter course to port with another vessel approaching forward of your beam as you should always pass port to port. If your radar indicates a close-quarters situation developing take early and substantial avoiding action.
Required sound signals include prolonged (4 to 6 seconds) and short (1 second) blasts, and must be made at intervals of two minutes or less:
Power vessel underway/making way………. 1 prolonged blast
Power vessel underway/not making way…… 2 prolonged blasts
All other vessels……… 1 prolonged then 2 short
Manned vessel being towed………… 1 prolonged then 3 short