Safety signs explained: colours, shapes and ISO 7010
What each type of safety sign means, what ISO 7010 codes are, and how to choose the right size.
Safety signs use a fixed set of colours, shapes and symbols so that anyone can understand them at a glance, whatever language they speak. This guide explains what each type means, what ISO 7010 is, and how to choose the right size.
Do I have to put up safety signs?
In Great Britain, the Health and Safety (Safety Signs and Signals) Regulations 1996 require employers to provide safety signs where a risk cannot be avoided or adequately controlled in other ways. Signs do not replace other controls; they warn people about the risk that remains. Your risk assessment, and for fire exits your fire risk assessment, tells you which signs you need and where. If you are unsure, the Health and Safety Executive publishes free guidance on safety signs.
The five types of safety sign
| Type | Shape and colour | Meaning | Example |
|---|---|---|---|
| Prohibition | Red circle with a diagonal bar, black symbol on white | You must not do this | No smoking |
| Mandatory | Blue circle, white symbol | You must do this | Safety helmets must be worn |
| Warning | Yellow triangle with a black border, black symbol | Be careful, there is a hazard | Caution fork lift trucks |
| Safe condition | Green square or rectangle, white symbol | The way to safety or first aid | Fire exit and emergency escape signs |
| Fire equipment | Red square or rectangle, white symbol | Where fire fighting equipment is | Fire alarm call point |
Signs that only carry text, such as many site and information notices, use the same colour meanings so people read them the right way.
What is ISO 7010?
ISO 7010 is the international standard that sets out registered safety sign symbols. Each symbol has a code: the letter shows the type (E for safe condition, F for fire equipment, M for mandatory, P for prohibition, W for warning) and the number identifies the symbol. For example, W014 is the warning symbol for forklift trucks and M014 is the mandatory symbol for wearing a safety helmet. Where one of our signs uses an ISO 7010 symbol, the code is shown on the product page so you can match it to your risk assessment. Signs whose message has no matching ISO symbol are made as clear text signs rather than with a symbol that does not fit.
What size safety sign do I need?
A sign is only useful if it can be read from where people are when they need it. As a conservative guide we allow 1 metre of viewing distance for every 25 mm of the sign’s shorter side:
| Sign size | Readable up to about |
|---|---|
| A4 (210 x 297 mm) | 8 m |
| A3 (297 x 420 mm) | 12 m |
| A2 (420 x 594 mm) | 17 m |
| A1 (594 x 841 mm) | 24 m |
Each safety sign page shows this table for the sizes that sign comes in. In poor light, or where people are moving fast, go a size up.
Which material?
For indoor walls and doors, 3 mm Foamex or self-adhesive vinyl is usually enough. For outdoor and long-term signs, choose 3 mm Dibond aluminium composite. For temporary site signs, Correx is light and weatherproof. Our sign materials guide compares them side by side.
Where to start
- Fire safety signs
- Warning signs
- Prohibition signs
- Mandatory signs
- Construction site signs and site safety boards
Need a sign you cannot find? Tell us the wording and size and we will quote it. Call 0161 315 1151 or use the contact form.