Isolated Danger Marks
If there is a danger such as a rock or wreck that has deep water all round, it may be marked by an isolated danger marker.
Isolated danger mark.
Frequently these are beacons mounted directly on to the danger.
Normally a pillar buoy or, a pole beacon.
All isolated danger marks have red and black horizontal stripes with two black balls for a topmark.
The light will always be white, and have a sequence with 2 flashes. An example of an Isolated danger beacon is Rod's Skerry on chart 4F at (46°13.41'N 05°352.86'W).
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