Chapter 5: Navigation Rules

Using Sound Signals in Darkness and Restricted Visibility

One needs to adjust speed to match the conditions out on the water. If visibility is limited by rain, fog, mist, or snow one must slow down to give ample time to avoid hazards or another vessel. If operating a powered vessel, proceed with caution and be ready to act with immediacy if necessary. In the case of a vessel detecting another by way of radar, one must use their knowledge to determine if one is in danger of a collision and if so, respond with appropriate and early action in order to avoid it.

With visibility limited, one absolutely needs to listen out for sound signals. Keep communicating with fellow boaters in order to stay safe and avoid a collision. Reduce speed until the other boater's intentions are clear.

Boat Navigation Lights

Power Vessel:

  • Underway: One prolonged blast every two minutes.
  • Underway but stopped: Two prolonged blasts every two minutes.

Sailing Vessel:

  • Underway: One prolonged blast and two short blasts every two minutes.

The following sound signals apply to ANY VESSEL:

Anchored: Five seconds of rapid bell ringing every minute.

Run Aground: Three bell stokes followed by five seconds of rapid bell ringing followed by three bell strokes every minute. 

If one hears any of these signals, reduce speed to the minimum speed necessary to maintain course. Keep moving at this minimum speed and proceed with caution. If one hears these signals from ahead, maintain this minimum speed and communicate with the fellow boater to ensure one fully understands the other's intentions. Only increase speed if at risk of a collision and the need to take evasive action arises.