New dangers: blue/yellow is a specific temporary identity

A new danger is a recently discovered hazard that may not yet appear in nautical charts and publications. It can be natural or man-made: a newly identified bank, obstruction or wreck, for example.

Newness describes the available information. It does not imply that the object itself is recent, or that all marking is removed after one fixed period.

The emergency wreck mark has blue and yellow vertical stripes in equal number and dimensions. R1001 specifies four to eight stripes around the body; a flat view does not show every side.

The body is pillar or spar. The topmark, if present, is an upright/perpendicular yellow cross, preferably three-dimensional.

Its arms are vertical and horizontal, unlike the diagonal yellow X of a special mark.

The colours alternate, with darkness between phases. They do not overlap to create a mixed-colour light.

The calculation is 1 + 0.5 + 1 + 0.5 = 3 seconds. IHO notation can appear as Al.Oc.BuY.3s: alternating, blue/yellow and period.

Phase durations come from the technical description rather than guesses from the abbreviation. The figure’s timeline helps recognise this characteristic without simulating an operational light.

Depending on context, suitable lateral, cardinal or isolated danger marks, or an emergency wreck buoy, can be used. A lit lateral used for this purpose has Q or VQ in the consulted provisions.

If the authority considers navigation risk especially high, at least one mark should be duplicated; the duplicate should be identical to its partner. This concerns management of marking, rather than instructions for owners to deploy aids.

A racon coded Morse D and AIS AtoN can supplement the information.

The hazard can remain while its marking changes. The recommendation relates new-danger status to removal of the hazard or sufficient dissemination of its information, as determined by the competent authority.

A virtual electronic aid can exist without a corresponding physical buoy. A photograph lacking a buoy therefore does not prove absence of a danger, and a display symbol does not prove that a floating body will be visible at that point.

Official notices form part of current information alongside chart edition.

Compare two dates in a record: discovery of the danger and installation of its aid. They can differ.

A third date can concern dissemination in a notice or chart. This timeline explains why “temporary” does not mean “the danger disappears”: information and marking arrangements evolve while the obstruction can remain.

The lesson records source edition and consultation date without presenting either as current confirmation of a particular buoy. Documentary history and physical history are related but separate.