Fire extinguisher colours are designed to help people quickly identify the type of extinguisher in an emergency. But over time, the colour system has changed — and relying on colour alone can now be misleading.
Important: In the UK, extinguisher labels matter more than colour. Always check the fire classes shown on the front.
Why fire extinguisher colours exist
Historically, fire extinguishers in the UK were colour-coded so users could quickly identify which extinguisher to use. This made sense when each extinguisher type tackled only one or two specific fire risks.
However, modern fire extinguishers are more versatile, and regulations have evolved. Today, colour is only a guide — not a guarantee.
Current UK fire extinguisher colour codes
For Class A fires involving wood, paper, and textiles. Not suitable for electrical or flammable liquid fires.
Covers multiple fire types but creates heavy residue and reduced visibility. Often avoided indoors.
Commonly used for electrical fires. Limited cooling effect and high re-ignition risk.
Used for Class A and B fires. Many foam extinguishers are now being phased out due to PFAS concerns.
Designed primarily for cooking oil fires (Class F), such as commercial kitchens.
Why colour alone is no longer enough
UK standards now require most fire extinguishers to be predominantly red, with only a small coloured band to indicate the extinguishing agent.
This change reflects a simple reality: modern extinguishers often cover multiple fire classes, and the label provides far more accurate information than colour.
Where water mist fits into the colour system
Water mist extinguishers are typically red with a white or silver label, and their fire coverage cannot be understood from colour alone.
They are increasingly used because a single unit can cover multiple fire types, including electrical equipment, while leaving minimal residue.
Note: Always follow your fire risk assessment and relevant British Standards when selecting extinguishers.