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Meaning of safety signs used in modern cargo ships

How to use safety Signs and notices ?

Safety signs should be used to indicate hazards or control measures to be taken where the hazard cannot otherwise be removed. The international standards for safety signs are explained in the following paragraphs.



Permanent signs are used:

i) to give prohibitions, warnings and mandatory requirements

ii) to mark emergency escape routes

iii) to identify first aid facilities

iv) to show the location of fire fighting equipment.


Red signs mean either:

i) stop doing something (prohibition); ii) stop/shut down or evacuate; or they mark the location and type of fire-fighting equipment.

Signs of prohibition are based on a red circular band with a red diagonal bar and white backing. The symbol for the prohibited action is shown in black behind the red diagonal bar; for example. `No Smoking' with a cigarette depicted.

A sign indicating fire-fighting equipment is a red square or rectangle, with information given in words or by a symbol in white. Alternatively an IMO sign is a square or ectangle, with information given in words or by a symbol in red.


Yellow signs are advisory and mean: be careful, or take precautions;

Warning signs are based on a yellow triangle with a black border. The symbol for the hazard is shown in black: for example, poisoning risk with black skull and crossbones on the yellow background.


Blue signs are mandatory and mean: take specific action.

Mandatory signs are based on a blue disc. The symbol for the precaution to be taken is shown in white; for example, `Goggles to be worn' with a man's head with goggles depicted. If, exceptionally, no suitable symbol is available, appropriate wording may be used instead: for example, `Keep Clear'.


Green signs mean:
i) emergency escape; or
ii) first aid sign.
The sign is a green square or rectangle, with safety information shown by words or a symbol in white. for example, a white arrow on a green background points to an emergency exit.

If more information is needed to make clear the meaning of any symbols used in a safety sign or notice , then a supplementary sign with text only may appear below the sign: for example, `Not Drinking Water'.


The supplementary sign should be oblong or square and either: (a) white with text in black; or (b) the same background colour as the safety colour used on the sign it is supplementing, with the text in the relevant contrasting colour.

Shore based personnel and passengers may not be aware that they are colour blind, and colour should not be used as a sole indicator.

Where a language other than English is extensively used on a ship, any text used in conjunction with a sign should usually be displayed also in that language.


Occasional signs

Illuminated signs, acoustic signals, hand signals and spoken signals may also be used for temporary hazards or circumstances. Illuminated signs and acoustic signals must be tested regularly to ensure that they are working. Acoustic signs should comply with the IMO Code on Alarms and Indicators 1992.


Spoken signals should comply with the IMO Standard for Marine Navigational Vocabulary. This is particularly important when communicating with another ship or with shore-side workers abroad, where English is not much used.




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