In fog, which action is correct when you hear a fog signal from ahead?

• A. Stop and reverse course
• B. Increase engine speed to pass
• C. Ignore the signal and proceed
• D. Slow to bare steerageway and navigate with caution

Answer: (D)

In fog, hearing a fog signal from ahead means another vessel is nearby in front of you, and you must be prepared to take early action to avoid a collision. The safest approach is to reduce speed to the minimum at which you can still steer and stop if needed—this is known as proceeding at bare steerageway. By moving that slowly, you keep maximum maneuverability to avoid the other vessel and you have time to assess its course and speed.

Navigate with caution means maintain a vigilant lookout, monitor progress of the other vessel, and avoid any course changes or actions that could create a new risk. This approach aligns with operating rules in restricted visibility, which require a safe speed and readiness to take action to prevent collision.

The other options aren’t appropriate: speeding up while fog signals are in use increases the chance of a collision; stopping or reversing abruptly can confuse or trap other vessels and is not the standard precaution in this situation; and ignoring the signal is unsafe and unlawful.