Chart symbols
Th
The e seseafafararining g nanatitionons s of of ththe e woworlrld d - - mmemembebers rs of of ththee InternationalInternational Hydrographi
Hydrographic c OrganizationOrganization - agreed in 1982 on an universal set of chart- agreed in 1982 on an universal set of chart symbols, abbreviations, colours, etc to be used in the nautical chart, in order symbols, abbreviations, colours, etc to be used in the nautical chart, in order to obtain
to obtain uniformity.uniformity.
On
On regular regular charts charts a a white, white, red, red, yellow yellow or or green green lights lights will will be be indicated indicated by by ,, and on GPS displays and modern multi-coloured charts in specific colours:
and on GPS displays and modern multi-coloured charts in specific colours:
, with the yellow coloured
, with the yellow coloured lobe indicating a white light.lobe indicating a white light.
The precise position of a chart symbol is its center, or is indicated with a line The precise position of a chart symbol is its center, or is indicated with a line and
and circle circle , , the the “position “position circle”.circle”.
Two distinct types of sea mark are drawn differently in the chart:
Two distinct types of sea mark are drawn differently in the chart:
beacons
beacons - fixed to the - fixed to the seabed; drawn upright;seabed; drawn upright;
buoys
buoys - consisting of a floating object that is usually anchored to a specific- consisting of a floating object that is usually anchored to a specific lo
locacatition on on on ththe e sesea a flfloooor; r; drdrawawn n at at an an obobliliquque e ananglgle e anand d wiwith th obobliqliqueue numbering, descriptions of colours
numbering, descriptions of colours and light and light characteristcharacteristics.ics.
Maj
Green or black buoys (symbols filled black):
Green or black buoys (symbols filled black): GG == Green ;
Green ; BB = Black= Black
Green or black beacon (symbol filled
Green or black beacon (symbol filled black). Noteblack). Note the upright G, instead of an oblique
the upright G, instead of an oblique GG Si
Singngle le cocololourured ed bubuoyoys s ototheher r ththan an grgreeeen n anandd black:
black: Y Y = Yellow ;= Yellow ; RR = Red= Red
Coloured beacon other than green and black, the Coloured beacon other than green and black, the symbol is again filled black so only the shape of symbol is again filled black so only the shape of the topmark is
the topmark is of navigational significance.of navigational significance.
Multiple colours in horizontal bands, the colour Multiple colours in horizontal bands, the colour sequence is from top to
sequence is from top to bottombottom Mul
Multiptiple le colcolourours s in in ververtictical al or or diadiagongonal al ststripripes,es, the darker colour is given first.
the darker colour is given first. W W = White= White
Spar buoy (here a safe water mark) Spar buoy (here a safe water mark) Lig
Lighthted ed mamarks rks on on mumultilti-co-colouloured red chachartsrts, , GPSGPS displays and chart plotters.
displays and chart plotters.
Lighted red beacon on
Lighted red beacon on standard charts.standard charts.
Re
Red d bbeaeaccon on aand nd grgreeeen n bbuuoy oy wwitith h ttopopmmaarkrk,, co
cololourur, , raradadar r rereflflecectotor r anand d dedesisigngnatatioion. n. ReRedd buoys and marks are given
buoys and marks are given even numbers, greeneven numbers, green buoys and marks are given odd numbers.
buoys and marks are given odd numbers.
Wave-actuated bell buoy to the left, and to the Wave-actuated bell buoy to the left, and to the right a Light buoy, with a horn giving a single right a Light buoy, with a horn giving a single bla
The
The fog fog signsignal sal symbymbol ol may may be obe omittmitted wed when hen aa description of the signal is given.
description of the signal is given.
Leading beacons
Leading beacons - Leading line (firm line is the- Leading line (firm line is the track to be followed)
track to be followed) Lead
Leading ing lighlightsts (≠ : (≠ : anany y twtwo o obobjecjects in ts in lilinene under each other). Bearing given in degrees and under each other). Bearing given in degrees and min
minuteutes. s. ThThe e liglights hts are are synsynchchronronizeized. d. ThThe e redred light has a shorter nominal range (the distance light has a shorter nominal range (the distance from which the light can be seen): 10 nautical
Sector light on multi-coloured charts.multi-coloured charts.
The elevation is 21 metres (height of the light The elevation is 21 metres (height of the light structure above chart
structure above chart datum)datum)..
Th
The e nonommininaal l raranngge e of of tthhe e whwhitite e lilighght t is is 1188 nautical miles. The range of the green and red nautical miles. The range of the green and red light is 12 nautical miles.
light is 12 nautical miles.
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Main n liglight ht visvisiblible e allall-ro-rounund d wiwith th red red susubsibsidiadiaryry light seen over danger. The fixed red light has an light seen over danger. The fixed red light has an elevation of 55 metres and a nominal range of elevation of 55 metres and a nominal range of 12 nautical miles. The flashing light is white,
12 nautical miles. The flashing light is white, withwith th
threree e flflasashehes s in in a a pepeririod od of of 10 10 sesecocondnds. s. ThThee elevation is higher than the red light: 62 metres elevation is higher than the red light: 62 metres and the
and the ranrange ge of of ththe e whwhite light is ite light is 25 25 nanautiuticalcal miles.
miles.
Symbol showing direction of buoyage (where not Symbol showing direction of buoyage (where not obvious)
obvious)
Symbol showing direction of buoyage (where not Symbol showing direction of buoyage (where not ob
obviviouous)s), , on on mumultlti-i-cocololourured ed chchararts ts (r(red ed anandd green circles coloured as appropriate), here IALA green circles coloured as appropriate), here IALA A
A
Full example of a light description in the chart Full example of a light description in the chart::
Fl(3)WRG.15s21m15-11M Fl(3)WRG.15s21m15-11M
Class of light
Class of light: group flashing repeating a group of three : group flashing repeating a group of three flashes;flashes;
Colours
Colours: : whwhitite, e, rered, d, grgreeeen, n, exexhihibibititing ng ththe e didiffffererenent t cocololoururs s in in dedefifinenedd
sectors;
sectors;
Period
Period: the time taken to exhibit one : the time taken to exhibit one full sequence of 3 flashes and eclipses:full sequence of 3 flashes and eclipses:
15 seconds;
15 seconds;
Elevation of light
Elevation of light : 21 metres;: 21 metres;
Nominal range(s)
Nominal range(s): white 15 M, green 11 M, red between 15 and 11 M,: white 15 M, green 11 M, red between 15 and 11 M, where “M” stands for nautical miles.
where “M” stands for nautical miles.