What are the five types of fire extinguisher?

The five you meet on a UK construction site are water, foam, dry powder, carbon dioxide and wet chemical. They are all predominantly signal red, and they are told apart by a colour-coded band or panel: cream for foam, blue for dry powder, black for carbon dioxide and yellow for wet chemical. Water is the exception, carrying no contrasting band because the plain red body is itself the identifier.

What colour is a foam fire extinguisher?

The body is signal red like every other extinguisher made to the current standard, with a cream band or panel above the operating instructions. Cream bodied foam extinguishers belong to the older scheme, where the whole body was painted in the identifying colour. If you answer with body colours you will be describing extinguishers that predate the standard now in use.

Why is there no class E fire?

Because electricity is a source of ignition rather than a fuel. It is not the electricity that burns, it is whatever the current sets alight, so an electrical fire can fall into any of the other classes. The letter E is not used at all: extinguishers suitable for live electrical equipment carry an electric spark symbol instead.

Which fire extinguisher is used on electrical fires?

HSE tells construction sites to provide carbon dioxide for electrical fires, water for wood, paper and cloth, and dry powder or foam for flammable liquids. Switch the equipment off first if you safely can, because until it is isolated the ignition source is still there.

What is a class F fire?

A fire involving cooking oils and fats, such as a deep fat fryer or a canteen range. It gets its own class because burning fat re-ignites so readily: the class F test requires an extinguisher to hold the fire out for a full 10 minutes without it catching again. The wet chemical extinguisher, the one with the yellow band, is the type made for it.

Are old colour coded fire extinguishers illegal?

No. Extinguishers painted entirely in the identifying colour under the older standard are still legal and do not have to be swapped out, according to the Fire Safety Advice Centre, until one is defective and needs replacing. That is exactly why both schemes turn up on real sites and why you should read the label rather than trust the paint.

Fire Extinguisher Types

Published 1 August 2026

UK construction sites keep extinguishers at identified fire points, and the CITB HS&E test you sit for your CSCS card expects you to match the right one to what is burning. Five types cover almost everything you will meet on a UK construction site, every one of them is predominantly red, and what tells them apart is a small coloured band.

The five fire extinguisher types

The last column is where marks are lost. The wrong extinguisher on the wrong fire can spread it, conduct electricity back to you, or let it reignite once you have walked away.

Type	Colour band	What it is for	What it must not be used on
Water	Signal red all over, so no contrasting band	Class A solids: wood, paper, fabrics. It cools the burning material	Flammable liquids, and anywhere electricity is involved
Foam	Cream	Class A and class B. It blankets the surface of a burning liquid	Fires involving electricity, and cooking oil fires
Dry powder	Blue	Class A, B and C, and electrical equipment. It knocks the flames down	Confined spaces, where the cloud can destroy visibility or worsen breathing difficulties
Carbon dioxide	Black	Electrical apparatus and class B flammable liquids	Solids. It does not cool, so a class A fire can take hold again. Treat a confined or poorly ventilated space as a further hazard in its own right: the discharge displaces air, and the horn gets cold enough to injure a bare hand
Wet chemical	Yellow	Class F cooking oil and fat fires, in canteens and site kitchens. Many models are rated for class A as well, so check the label rather than assuming it is single purpose	Liquid, gas and electrical fires

Class D metal fires need a specialist powder rather than the ordinary ABC powder in the table above, and it carries the same blue band. Specialist powder is rare on general construction sites and is usually provided only where a known metal risk has been assessed.

Fire extinguisher colours: band, not body

This is the single most misremembered fact in the whole subject. Extinguishers manufactured to BS EN 3-7 are predominantly signal red. The type is shown by a label, band or panel in a second colour, covering at least 5% of the surface, normally sited just above the operating instructions. Water is the exception only because its identifying colour is red anyway, so there is nothing to contrast with.

The older British scheme did paint the entire body: cream for foam, blue for powder, black for carbon dioxide. Those extinguishers are still legal and stay in service until they are defective, which is why you will meet both schemes on the same site. Revision material that tells you to look for a cream extinguisher is describing the scheme that was replaced, not the one on the wall. Kit bought for a UK site should conform to BS EN 3 and BS 7863, and the Kitemark or the BAFE mark on the extinguisher is what confirms it.

The classes of fire

A fire is classified by what is burning, not by how it started. The class is what decides the extinguisher.

Class A: organic solids such as wood, paper and textiles
Class B: flammable liquids such as petrol and spirits. Cooking oil is not class B, it is class F. Alcohol is a class B liquid, but water-based media including standard foam are ineffective on it, so check the extinguisher is rated for alcohol before reaching for one
Class C: flammable gases such as propane and butane
Class D: burning metals such as magnesium, lithium and aluminium swarf
Class F: cooking oils and fats, for example in a deep fat fryer

Extinguishers rated for class A, B or F also carry a fire rating, a number and a letter together such as 13A or 55B. The number describes the size of test fire the extinguisher put out, so a bigger number means a bigger capability. Classes C and D and the electrical symbol carry no numerical rating.

The exam point: there is no class E

The list runs A, B, C, D and F. E is missing on purpose. Electricity is a source of ignition, not a fuel: nothing about the current itself burns, so what you actually have is the surrounding material alight, which already falls into one of the other classes. Because of that, electrical fires are not given a class of their own and the letter E is not used. Extinguishers suitable for live electrical equipment show an electric spark symbol instead of a letter.

It follows that the first move on an electrical fire is to cut the power, if you can reach the isolator safely. Leave it live and the ignition source is still working while you fight the flames. Practise this alongside the electrical safety questions, where the same reasoning decides several answers.

What HSE tells construction sites

HSE keeps the matching rule short for site use. Extinguishers should be located at identified fire points around the site and be appropriate to the nature of the potential fire:

wood, paper and cloth: water extinguisher
flammable liquids: dry powder or foam extinguisher
electrical: carbon dioxide extinguisher

HSE also expects nominated people to be trained in how to use them. On site the legal frame is the Regulatory Reform (Fire Safety) Order 2005, which requires a responsible person, usually the main or principal contractor, to carry out and keep up to date a fire risk assessment and put the resulting precautions in place. Alongside it, the CDM Regulations 2015 require arrangements for foreseeable emergencies to be made and tested, and emergency routes and exits to be kept clear, free from obstruction and marked with suitable signs.

None of that turns you into a firefighter. Raise the alarm first, only tackle a fire in its earliest stage, keep your escape route behind you, and get out if the extinguisher empties or the fire does not go out.

Where this fits in your revision

Fire questions rarely arrive on their own. The flame pictogram covered in COSHH symbols is telling you what class of fire a drum would give you, which is why the hazardous substances questions and asbestos awareness sit close to this topic on refurbishment jobs. RIDDOR covers the reporting duties that follow an incident, and types of PPE covers the hierarchy that puts removing the fuel or the ignition source well above protecting one person from it. The full set of CSCS test questions and answers is arranged by topic.

Practise the fire safety questions

Extinguisher types come up in the fire section and again in the emergency procedures questions. Work through the fire safety and emergency procedures questions with explanations, or sit a full free CSCS practice test to find out whether you actually know the bands or just recognise them.

Fire safety practice questions Full 50-question mock

Fire extinguisher types: common questions

What are the five types of fire extinguisher?: The five you meet on a UK construction site are water, foam, dry powder, carbon dioxide and wet chemical. They are all predominantly signal red, and they are told apart by a colour-coded band or panel: cream for foam, blue for dry powder, black for carbon dioxide and yellow for wet chemical. Water is the exception, carrying no contrasting band because the plain red body is itself the identifier.
What colour is a foam fire extinguisher?: The body is signal red like every other extinguisher made to the current standard, with a cream band or panel above the operating instructions. Cream bodied foam extinguishers belong to the older scheme, where the whole body was painted in the identifying colour. If you answer with body colours you will be describing extinguishers that predate the standard now in use.
Why is there no class E fire?: Because electricity is a source of ignition rather than a fuel. It is not the electricity that burns, it is whatever the current sets alight, so an electrical fire can fall into any of the other classes. The letter E is not used at all: extinguishers suitable for live electrical equipment carry an electric spark symbol instead.
Which fire extinguisher is used on electrical fires?: HSE tells construction sites to provide carbon dioxide for electrical fires, water for wood, paper and cloth, and dry powder or foam for flammable liquids. Switch the equipment off first if you safely can, because until it is isolated the ignition source is still there.
What is a class F fire?: A fire involving cooking oils and fats, such as a deep fat fryer or a canteen range. It gets its own class because burning fat re-ignites so readily: the class F test requires an extinguisher to hold the fire out for a full 10 minutes without it catching again. The wet chemical extinguisher, the one with the yellow band, is the type made for it.
Are old colour coded fire extinguishers illegal?: No. Extinguishers painted entirely in the identifying colour under the older standard are still legal and do not have to be swapped out, according to the Fire Safety Advice Centre, until one is defective and needs replacing. That is exactly why both schemes turn up on real sites and why you should read the label rather than trust the paint.

Checked August 2026 against the pages we actually read. Fire points, the water, foam and carbon dioxide matching rule and the responsible person duty: HSE general fire safety for construction, hse.gov.uk/construction/safetytopics/generalfire.htm. The per type descriptions, the powder in confined spaces warning and the BS EN 3 and BS 7863 conformance point: Dorset and Wiltshire Fire and Rescue Service, dwfire.org.uk. The colour band scheme, the classes of fire, the absence of a class E, the fire ratings and the code for tackling a fire: the Fire Safety Advice Centre, firesafe.org.uk. Emergency arrangements and emergency routes: regulations 30 and 31 of the Construction (Design and Management) Regulations 2015, legislation.gov.uk. BS EN 3-7 is a paywalled standard and was not read.