Wednesday, December 08, 2010

Five Tips To Fight Fog

You can't make the fog go away, but you can wait it out safely with these tips and a bit of common sense. Here's what to do when the fog rolls in, whether you are operating a small boat or a large yacht or ship - by guest contributor Vincent Pica
U.S. Coast Guard photo by PO2 Etta Smith

By Vincent Pica
District Captain, Sector Long Island Sound/South, D1SR
United States Coast Guard Auxiliary

For those of a more scientific-bent, fog that forms when water is warmer than the air is called “steam” fog (most often occurs in the Fall). Think of that pot of spaghetti water you are boiling. Fog that forms when the water is colder than the air is called “advection” fog (Spring). There is a third kind of fog called “radiation” fog. That is the fog that you see float in across the backyard or linger in a dip in the country road…

But fog is fog. You can’t see the land or the buoys or, worse, the bow of your own boat! What to do?

Not surprisingly, the advice below holds for the 65’er with radar and chart overlay capabilities as well as the skipper in the 17’ open boat with a 90-hp Merc on the stern. When the fog rolls in…
  1. Slow down to “a slow bell”, that is, with forward propulsion necessary to maintain steerage, but no greater. Put on life jackets. (see Life Jackets – Do I Really Need To Wear One?)
  2. While underway and making way, that is, engine in gear, give 1 “prolonged” blast on your whistle (4-6 seconds). This is specified in the Navigation Rules, Rule 35(a) (see COLREGs: What’s That I Hear?) In fact, the Rules say “not more than 2 minutes apart.” Let me make it plainer. No LESS than every 2 minutes.
  3. While underway but not making way, that is, dead stop on the engine but not at anchor, give 2 “prolonged” blasts, separated by a couple of seconds apart, no less than every 2 minutes. This is Rule 35(b).
  4. If necessary to anchor due to visibility (none!), “boats less than 39 feet 4 inches (12 meters) in length may make an efficient sound signal at intervals of not more than two minutes.” In short, it is not specified for boats under 12 meters. Boats larger than 12 meters at anchor must clang their bell 5 times quickly followed by one prolonged and one short (~1 second) blast in the whistle.
  5. Listen. Sound travels more efficiently through fog than clear air. Listen. Bring your engine to dead stop from time to time and listen. Listen for the sound of surf (move away from that!), buoy whistles/horns/bells (move towards that, carefully) or other engines (sound danger whistle right away and take all way off – but don’t turn off the engine!)

So, now you are properly communicating with other boats but you do want to get in out of the fog if you can. How? Don’t, as some old chestnuts might advise, hug the shore. As the fog intensifies and you draw closer and closer to shore, you know what will happen – you will be capsized and now there is imminent threat to life. (See column on what to do if you run aground (see Hard Aground, Now What!?)

If you can’t see, you must stop, drop the hook, sound your warning horn as specified and wait out the fog. If due to electronics (GPS, Loran) you realize that you are in a heavy traffic lane, get out - at a slow speed and just enough to be out of the traffic. But if you can’t see past the bow and you are underway and making way, you are in extreme danger of having a collision at sea.

If you have some visibility, see #’s 1 and 2 above. The slower speed will help in another way as well – you can hear better. Lastly, if you have those canisters of compressed gas as your boat’s horn/whistle, you will likely run out of compressed air before you run out of fog. Think about getting a simple whistle. Get the “pea-less” kind in case you have to worry about your spittle freezing one cold and foggy day… and blow, baby, blow…!

You can learn more about Captain Pica and get more tips like this at his site,


1 comment:

  1. Thanks for the safety tips. As always verifiable and useful information for all boaters.