Safety Sign Colours and Meanings
Safety signs use standard combinations of colours, shapes and pictograms so that important information can be understood quickly.
Knowing what the different safety sign colours mean can help workers, contractors and visitors recognise whether a sign is warning about a hazard, prohibiting an action, requiring particular behaviour or showing emergency information.
Here is a straightforward guide to the most common UK workplace safety signs.
What Do the Different Safety Sign Colours Mean?
The four colours most frequently seen on workplace safety signage are:
Red – prohibition and certain fire safety information
Yellow or amber – warning
Blue – mandatory action
Green – safe conditions, emergency escape and first aid
The shape and pictogram are also important, rather than colour being used on its own.
Red Safety Signs: Prohibition
Red is commonly used for prohibition signs.
These tell people that a particular action or behaviour is not permitted.
Prohibition signs generally use:
A circular shape
White background
Black pictogram
Red border
Red diagonal line
Common examples include:
No smoking
No entry
No unauthorised access
No pedestrians
Do not touch
No mobile phones
On construction sites and industrial premises, these signs can help restrict access to potentially dangerous areas or prevent behaviour that could introduce additional risks.
Yellow Safety Signs: Warning
Yellow or amber safety signs warn people about a hazard or danger.
Warning signs typically use:
A triangular shape
Yellow background
Black border
Black pictogram
Examples include:
Warning – electricity
Warning – forklift trucks
Warning – overhead load
Warning – slippery surface
Warning – trip hazard
Warning – moving vehicles
Warning – hazardous substance
The aim is to make someone aware of the hazard before they encounter it.
Blue Safety Signs: Mandatory Actions
Blue safety signs generally tell people that a particular action must be taken.
Mandatory signs usually use:
A circular shape
Blue background
White pictogram
PPE signs are among the most familiar examples.
Typical messages include:
Safety helmets must be worn
Hi-vis clothing must be worn
Safety footwear must be worn
Eye protection must be worn
Hearing protection must be worn
Gloves must be worn
Pedestrians must use this route
Blue signs are therefore particularly common on construction sites, factories, workshops and industrial premises.
Green Safety Signs: Emergency and Safe Conditions
Green safety signs identify safe conditions, emergency escape routes and first aid facilities.
They commonly use:
A rectangular or square shape
Green background
White pictogram
Typical examples include:
Fire exit
Emergency exit
First aid
Emergency shower
Eyewash station
Safe condition information
They help people find important facilities or routes quickly, particularly during an emergency.
What Colour Are Fire Safety Signs?
Fire safety signage can use different colours depending on its purpose.
For example, fire-fighting equipment signs commonly use red, whereas escape-route and emergency-exit signs generally use green.
This is why it is important to consider the sign's complete combination of colour, pictogram, shape and message.
Why Are Standard Safety Symbols Important?
A recognised pictogram can often communicate information more quickly than a large amount of written text.
Standardisation also means a worker, visitor or contractor is more likely to recognise the meaning of a sign even if they have not seen that particular sign before.
Sigma8 Signs can supply safety signage designed to support recognised safety-sign conventions, including appropriate ISO 7010-style safety symbols where applicable.
Does Every Hazard Need a Safety Sign?
No.
Safety signs are part of a wider health and safety system.
Where a risk can be removed or adequately controlled in another way, a sign should not be treated as a substitute for those controls.
Signage becomes important where a significant risk remains and people need clear information, warning or instruction.
Avoid Safety Sign Overload
More signs do not automatically mean a safer workplace.
Putting a large number of signs together can make important messages harder to notice.
Where several instructions apply at a site entrance, carefully designed multi-message signage or a site safety board may provide a clearer solution.
Elsewhere, individual signs can be positioned close to the hazard, instruction or equipment they relate to.
Where Should Safety Signs Be Positioned?
A safety sign needs to be visible before the person reaches the hazard or location where action is required.
Consider:
Viewing distance
Lighting
Obstructions
Sign size
Background contrast
Height
Weather exposure
The direction people approach from
Signs should also be maintained so they remain legible.
For a more detailed explanation, read our Where Should Safety Signs Be Placed? guide.
Shop Safety Signs from Sigma8 Signs
Sigma8 Signs supplies health and safety signage for construction sites, warehouses, factories, workshops, offices and commercial premises throughout the UK.
Our range includes warning signs, mandatory PPE signs, prohibition signs, emergency signs, fire safety signage, construction signs and bespoke safety signs.
Browse our health and safety signs or contact Sigma8 Signs for advice on sign types, materials, sizes and fixing options.