Navigation General · Special Marks & Ranges
An isolated danger mark is placed:
- AAt the centerline of a safe channel
- BOn or near a hazard with navigable water around it✓ Correct
- CAt the entrance to a restricted anchorage area
- DOn the preferred channel side of a junction
Explanation
An isolated danger mark is placed on or moored over a small, discrete hazard (shoal, wreck, rock) with navigable water surrounding it. Vessels should pass clear of the mark in any direction.
Authority: 33 CFR 62 (U.S. ATON System)
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