Wet Chemical Fire Extinguishers

Which fire extinguisher for cooking oil? A wet chemical extinguisher. It is the type designed for Class F fires involving cooking oils and fats, and you should never use water on them. A wet chemical fire extinguisher sprays a fine mist that cools the oil and forms a soapy layer on its surface to stop it re-igniting. Portable units are made to BS EN 3, with a red body and a yellow band or label.

Wet chemical fire extinguishers are designed for Class F fires involving cooking oils and fats, such as fryer fires in commercial kitchens, canteens and cafés. Browse 3, 6 and 9 litre wet chemical extinguishers from CheckFire, Jewel and Ceasefire.

Wet chemical extinguishers we stock

• CheckFire – Commander and CommanderEDGE 3 and 6 litre models, including PFAS-free versions rated up to 13A 75F, plus a stainless steel Contempo 3 litre. See CheckFire and Commander.
• Jewel – 3 litre (8A 25F) and 6 litre (13A 75F) models from Jewel Fire Group.
• Ceasefire – 3, 6 and 9 litre stored-pressure models in mild steel, stainless steel and chrome finishes, including lance and spray versions, with ratings up to 21A 75F. See Ceasefire.

How to choose a wet chemical fire extinguisher

• Understand the F rating. The number in a Class F rating (for example 25F, 40F or 75F) is the volume of cooking oil, in litres, used in the standard test fire. It is not the same as fryer capacity: BS 5306-8 bases minimum provision on the surface area of exposed cooking oil, so confirm what you need with your fire risk assessment or a competent person.
• Check the other classes. Most wet chemical models also carry a Class A rating for solid materials, and some Ceasefire spray models add a Class B rating.
• Identify it clearly. Wet chemical extinguishers are red with a canary yellow colour-coded area. Add a matching ID sign from our fire safety signs range and keep refills in stock from extinguisher spares.

Complete the kitchen fire point with fire extinguisher stands and cabinets. A fire blanket is a useful addition beside a wet chemical extinguisher for small kitchen fires. To learn how fire classes work, read Class F fires explained and fire extinguisher colours and types: where a wet chemical extinguisher fits.

Why buy from JEM Systems UK

JEM Systems UK is an authorised distributor of CheckFire, and every extinguisher we supply is genuine, brand new and factory sealed. Order online with fast, tracked UK delivery. Browse all fire extinguishers, or compare water mist, foam, CO2, powder, water and lithium-ion battery extinguishers.

Wet chemical fire extinguisher FAQs

What is a wet chemical fire extinguisher used for?

It is used on Class F fires involving cooking oils and fats, such as deep fat fryer fires. The agent, typically a solution of potassium salts, forms a soap-like layer on the burning oil that seals it from oxygen and helps it cool below its auto-ignition temperature, reducing the risk of re-ignition.

What colour is a wet chemical fire extinguisher?

Red, with a canary yellow colour-coded area identifying the wet chemical agent.

Where would you find a wet chemical fire extinguisher?

Wherever cooking oils and fats are used, such as commercial kitchens, restaurants, cafés, canteens and bakeries. The number and position of extinguishers should follow your fire risk assessment.

Why not use a water extinguisher on a cooking oil fire?

A water jet aimed at burning cooking oil turns to steam almost instantly and can throw burning oil out, spreading the fire and injuring the user. Powder and CO2 may knock down the flames, but without sealing the oil surface it can quickly re-ignite.

What is a Class F fire?

Class F fires involve cooking oils and fats, such as those in deep fat fryers. They burn hotter than ordinary flammable liquids and need an agent made for the job, which is why wet chemical extinguishers carry a Class F rating.

Which fire extinguisher is used in a commercial kitchen?

A wet chemical extinguisher for the cooking oil risk. BS 5306-8 gives guidance on selecting and positioning extinguishers, and many kitchens also keep a fire blanket and a second extinguisher type for other risks. Confirm the provision with your fire risk assessment.

Can a wet chemical extinguisher be used on other types of fire?

Most models also carry a Class A rating for solid materials such as wood, paper and textiles, but check the rating on the label. Do not use wet chemical on live electrical equipment unless the manufacturer states it is suitable.

What does 75F mean on a wet chemical extinguisher?

The number is the volume of cooking oil, in litres, used in the standard Class F test fire. A higher number shows the extinguisher passed a larger test, but it is not the same as the size of fryer it protects.