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SESK: Stuff Everyone Should Know · sesk.info/boat-fog-hear-signal-slow-down

In fog, you hear another boat's fog signal apparently ahead of your beam. What does Rule 19 say to do?

Slow to the minimum speed that keeps you on course.

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  1. Speed up to clear the area quickly
  2. Turn hard to port right away
  3. Slow to the minimum speed that keeps you on course ✔

Why: Rule 19(e) says if you hear a fog signal forward of your beam, slow to the minimum speed at which you can keep your course, stop if needed, and go with extreme caution until the danger is over.

Huh, didn't know that: Rule 19 also says a powerboat in restricted visibility must have its engines ready for immediate maneuver.

The dad joke
I tried to tell a joke in the fog. Nobody saw it coming.
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References

Answer: Slow to the minimum speed that keeps you on course. Rule 19(e) says if you hear a fog signal forward of your beam, slow to the minimum speed at which you can keep your course, stop if needed, and go with extreme caution until the danger is over.

  1. 33 CFR 83.19, Conduct of vessels in restricted visibility (Rule 19) www.ecfr.gov/current/title-33/section-83.19
    shall reduce her speed to the minimum at which she can be kept on course.
    Checked 2026-10-09.

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