Safe water mark
A Safe Water Mark, as defined by the International Association of Lighthouse Authorities, is a sea mark used in maritime pilotage to indicate the end of a channel. It usually implies that open, deep and safe water lies ahead, though it is sometimes also used to indicate the start and end of a buoyed section of a continuous narrow channel, or a line of these marks can be used to mark a safe route through shallow areas.[1] It is therefore important to consult an appropriate chart to determine the exact meaning in each case. The marker is also sometimes known as a Fairway Buoy.
It is recognisable by its red and white vertical stripes and commonly bears a top-sign in shape of a red ball. Lighted buoys either flash Morse code "A" (di-dah), or one long flash, occulting (more light than dark) or isophase (equal light and dark), every 10 seconds (L Fl 10s).[2]
In the United States, safe water marks have the initials of their associated waterways or localities printed on them.
See also
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References
- "Safe Water Marks" (PDF). IALA. Archived from the original (PDF) on 2007-12-14.
- NOAA Chart 37222. http://www.charts.noaa.gov/NGAViewer/37222.shtml See the vicinity of "Hubertgat"
- Haire, Penny.Yachtmaster. Royal Yachting Association, 2009, p. 61.