You should use sound signals to alert other boaters to your presence in the area, if visibility is restricted (due to fog, rain etc).
The following are examples of sound signals used in restricted visibility:
|Prolonged blast every two minutes.
|Prolonged blast + two short blasts every two minutes.
|Two prolonged blasts every two minutes.
|Five seconds of rapid blasts / bell ringing every minute.
|Three bell strokes + five seconds of rapid bell ringing + three bell
strokes every minute.