Key:seamark:light:visibility

seamark:light:visibility
Group: Marine navigation
Used on these elements
Documented values: 3
Status: undefined
More details at taginfo
Tools for this tag
Seamark tagging

Light

The tags defined on this page will render in various nautical charts.

This page defines values for the seamark:type=* tag for lights objects and their attribute tags.

Types

A light is a luminous or lighted aid to navigation.

Type S100 code seamark:type Definition Example renderings Photo
Major light LIGHTS light_major A major light is a light that is intended to be seen at extended distances and will indicate the presence of prominent land masses or provide guidance into harbours or rivers. This tag is used where the supporting structure is not specified, otherwise the seamark:type tag should take the value of the supporting structure (most often "landmark")
Minor light LIGHTS light_minor A minor light is a short-range light that marks obstacles in the same way as lighted buoys and beacons, otherwise the seamark:type tag should take the value of the supporting structure (most often "pile")
Light vessel LITVES light_vessel A distinctively marked vessel anchored or moored at a charted point, to serve as an aid to navigation. By night, it displays a characteristic light(s) and is usually equipped with other devices, such as fog signal, submarine sound signal, and radio-beacon, to assist navigation.
Light float LITFLT light_float A boat-like structure used instead of a light buoy in waters where strong streams or currents are experienced, or when a greater elevation than that of a light buoy is necessary.

Attributes

Colours

Lights have a single colour, except those with alternating characters, which have two colours.

Colour (COLOUR) seamark:light:colour Rendering
White white
Red red
Green green
Blue blue
Yellow yellow
Amber amber
Violet violet
Orange orange
Magenta magenta

Characters

Animated illustrations of light characters can be found here: light characters

Character (LITCHR) seamark:light:character Pattern Description
Fixed F A signal light that shows continuously, in any given direction, with constant luminous intensity and colour.
Flashing Fl A rhythmic light in which the total duration of light in a period is clearly shorter than the total duration of darkness and all the appearances of light are of equal duration.
Long-flashing LFl A flashing light in which a single flash of not less than two seconds duration is regularly repeated.
Quick-flashing Q A light exhibiting without interruption very rapid regular alternations of light and darkness.
Very-quick-flashing VQ A flashing light in which flashes are repeated at a rate of not less than 80 flashes per minute but less than 160 flashes per minute.
Ultra-quick-flashing UQ A flashing light in which flashes are repeated at a rate of not less than 160 flashes per minute.
Isophased Iso A light with all durations of light and darkness equal.
Occulting Oc A rhythmic light in which the total duration of light in a period is clearly longer than the total duration of darkness and all the eclipses are of equal duration.
Interrupted quick-flashing IQ A quick light in which the sequence of flashes is interrupted by regularly repeated eclipses of constant and long duration.
Interrupted very quick flashing IVQ A light in which the very rapid alterations of light and darkness are interrupted at regular intervals by eclipses of long duration.
Interrupted ultra quick flashing IUQ A light in which the ultra quick flashes (160 or more per minute) are interrupted at regular intervals by eclipses of long duration.
Morse Mo A rhythmic light in which appearances of light of two clearly different durations are grouped to represent a character or characters in the Morse code.
Fixed/flash FFl
Flash/long-flash FlLFl
Occulting/flash OcFl
Fixed/long-flash FLFl
Occulting alternating Al.Oc
Long-flash alternating Al.LFl
Flash alternating Al.Fl
Group alternating Al.Gr
Quick-flash plus long-flash Q+LFl
Very-quick-flash plus long-flash VQ+LFl
Ultra-quick-flash plus long-flash UQ+LFl
Alternating Al
Fixed and alternating flashing Al.FFl

Categories

Category (CATLIT) seamark:light:category Definition
Directional function directional A light illuminating a sector of very narrow angle and intended to mark a direction to follow. A light tagged with this category should also carry a "seamark:light:orientation" tag.
Leading light leading A light associated with other lights so as to form a leading line to be followed.
Aero light aero An aero light is established for aeronautical navigation and may be of higher power than marine lights and visible from well offshore.
Air obstruction light air_obstruction A light marking an obstacle which constitutes a danger to air navigation.
Fog detector light fog_detector A light used to automatically determine conditions of visibility which warrant the turning on or off of a sound signal.
Flood light floodlight A broad beam light used to illuminate a structure or area.
Strip light strip_light A light whose source has a linear form generally horizontal, which can reach a length of several metres.
Subsidiary light subsidiary A light placed on or near the support of a main light and having a special use in navigation.
Spotlight spotlight A powerful light focused so as to illuminate a small area.
Front front Term used with leading lights to describe the position of the light on the lead as viewed from seaward.
Rear rear Term used with leading lights to describe the position of the light on the lead as viewed from seaward.
Upper upper Term used with leading lights to describe the position of the light on the lead as viewed from seaward.
Lower lower Term used with leading lights to describe the position of the light on the lead as viewed from seaward.
Moire effect moire A short range (up to 2km) type of directional light. Sodium lighting gives a yellow background to a screen on which a vertical black line will be seen by an observer on the centre line.
Emergency light emergency A light available as a backup to a main light which will be illuminated should the main light fail.
Bearing light bearing A light which enables its approximate bearing to be obtained without the use of a compass.
Horizontally disposed horizontal A group of lights of identical character and almost identical position, that are disposed horizontally. A light tagged with this category should also carry a "seamark:light:multiple" tag.
Vertically disposed vertical A group of lights of identical character and almost identical position, that are disposed vertically. A light tagged with this category should also carry a "seamark:light:multiple" tag.

Sectored light attributes

Note that sectored lights must bear a sector number (1+) even if there is only one sector. For more information on tagging sectored and directional lights, see: sectored and directional lights.

Attribute seamark:light:#:<attribute> Value Definition
Sector limit one (SECTR1) sector_start Decimal degrees The sector limit 1 specifies the first limit of the sector. The order of sector limit 1 and sector limit 2 is clockwise around the light.
Sector limit two (SECTR2) sector_end Decimal degrees The sector limit 2 specifies the second limit of the sector. The order of sector limit 1 and sector limit 2 is clockwise around the light.

Light visibility

Visibility (LITVIS) seamark:light:visibility Definition
High intensity high Non-marine lights with a higher power than marine lights and visible from well off shore (often 'Aero' lights).
Low intensity low Non-marine lights with lower power than marine lights.
Faint faint A decrease in the apparent intensity of a light which may occur in the case of partial obstructions.
Intensified intensified A light in a sector is intensified (i.e. has longer range than other sectors).
Unintensified unintensified A light in a sector is unintensified (i.e. has shorter range than other sectors).
Visibility deliberately restricted restricted A light sector is deliberately reduced in intensity, for example to reduce its effect on a built-up area.
Obscured obscured Said of the arc of a light sector designated by its limiting bearings in which the light is not visible from seaward.
Partially obscured part_obscured Parts of the sector are obscured.

Exhibition conditions

Exhibition (EXCLIT) seamark:light:exhibition Definition
Light shown without change of character 24h A light shown throughout the 24 hours without change of character.
Daytime light day A light which is only exhibited by day.
Fog light fog A light which is exhibited in fog or conditions of reduced visibility.
Night light night A light which is only exhibited at night.
Warning warning A light which is exhibited to warn of a present or imminent danger.
Storm storm A light which is exhibited to warn of a present or imminent storm.

Other attributes

Attribute seamark:light:<attribute> Value type Definition
Focal height (HEIGHT) height Decimal The vertical elevation of the actual lamp or light source (in meters) above the specified vertical datum (typically, mean sea level) – known as the focal height.

Example: Lamp is 1.5 m below the roof of a 10 m lighthouse, atop a hill at elevation of 20 m above MSL. Then, seamark:light:height=28.5.

Luckily, most light lists already calculate the focal height.

Multiplicity of lights (MLTYLT) multiple Integer The number of lights of identical character that exist as a co-located group.
Nominal range (VALNMR) range Decimal The nominal range at which the light can be seen in nautical miles.
Signal group (SIGGRP) group Text The number of flashes, the combination of flashes or the Morse character(s) within one period of full sequence.
Signal period (SIGPER) period Decimal Time of the time occupied by an entire cycle of intervals of light and eclipse.
Signal sequence (SIGSEQ) sequence Text The sequence of times occupied by intervals of light and eclipse for all 'light characteristics' except for occulting where the sequence of times is occupied by intervals of eclipse and light.

Other objects

Lights may have other objects as part of their structure

Object S100 Definition Wiki page
Fog signal FOGSIG A warning signal transmitted by a vessel, or aid to navigation, during periods of low visibility. Also, the device producing such a signal. Fog signals
Radar transponder beacon RTPBCN A transponder beacon transmitting a coded signal on radar frequency, permitting an interrogating craft to determine the bearing and range of the transponder. Radar beacons
Radar reflector RADRFL A device capable of, or intended for, reflecting radar signals.
Radio station RDOSTA Radio navigation beacons and AIS transmitters Radio stations

Editing

Use the JOSM-seasign-Editor Plugin, or the "OpenSeaMap online editor". Both offer a graphical interface for adding details about angles and flashing rates.

References

OSM seamark resources

External sources

This article is issued from Openstreetmap. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.