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Understanding Safety Signs

The purpose of safety colours and safety signs is to draw attention rapidly to objects and situations affecting safety and health and to gain rapid understanding of a specific message. This is obtained by a combination of a colour and geometric shape and which, by the addition of a graphical symbol, gives a particular safety message. General signs are used for information purposes and are not required to meet any specific criteria. Traffic signs and braille signs do not follow these rules. Safety signs can be categorised as followed as specified by ISO 3864, Irish and EU Legislation.
Hazard Warning
Hazard Identification
Shape & Colour: Yellow triangle with black border.
Meaning: Potential hazard within a designated area, Caution / Risk of Danger.
Supplementary text may be added if necessary to convey a clearer message.
Prohibition
Prohibition Sign
Shape & Colour: Red circle with diagonal line.
Meaning: Behaviours that are prohibited. Do not do / You must not / Stop.
Supplementary text may be added if necessary to convey a clearer message.
Mandatory
Mandatory Sign
Shape & Colour: Solid Blue Circle
Meaning: You must do / Carry out course of action displayed on sign.
Supplementary text may be added if necessary to convey a clearer message.
Safe Condition
Safe Condition Signs
Shape & Colour: Solid green rectangle or square.
Meaning: Provides information about safe conditions and escape routes.
Supplementary text may be added if necessary to convey a clearer message.
Fire Equipment
Fire Equipment Signs
Shape & Colour: Solid red rectangle or square.
Meaning: Information on the location and / or use of fire fighting equipment.
Supplementary text may be added if necessary to convey a clearer message.
General Signs
General Signs
Shape & Colour: Various colours and shapes.
Meaning: Informational, follows no standard, used for non-safety purposes.
Supplementary text may be added if necessary to convey a clearer message.

Supplementary Signs

A supplementary sign, normally an additional panel containing text (the yellow, red, blue or green box accompaning the graphical symbol / safety sign) is supportive of a safety sign and the main purpose of which is to increase comprehension and provide additional clarification except when the safety sign is supplemented by manuals, instructions or training.

ISO 3864

ISO 3864 principles establish the safety identification colours and design principles for safety signs and safety markings to be used in workplaces and in public areas for the purpose of accident prevention, fire protection, health hazard information and emergency evacuation. It also establishes the basic principles to be applied when developing standards containing safety signs.
*The colour white includes the colour for phosphorescent material under daylight conditions with properties as defined in ISO 3864-4. It is essential to achieve a luminance contrast between the safety sign and its background as well as between the supplementary sign and its background on which they are mounted or displayed.

Scope of ISO 3864

ISO 3864 principles are applicable to most locations where safety issues related to people need to be addressed. However, it is not applicable to the signalling used for guiding rail, road, river, maritime and air traffic and, generally speaking, to those sectors subject to a regulation or countries' statutory regulations which may differ.
All statements, technical information and recommendations are based on data believed to be reliable. It is given in good faith but the accuracy and/or completeness is not guaranteed. The user shall determine the suitability of the product for their particular purpose and shall assume all risk and liability in connection herewith.