Fire Extinguishers: Types, Usage & Placement Guide

Fire Safety Guide #18 | A practical guide to extinguisher types, correct usage, and placement for maximum fire safety.

Fire extinguishers are one of the most recognisable fire safety tools — and for good reason. When used correctly, they can prevent a small fire from escalating into a life-threatening emergency. But not all extinguishers are the same, and choosing the right type — and placing it correctly — is essential for keeping people and property safe.

This guide explains the main extinguisher types, how to use them effectively, and the
key rules for correct placement.

The Five Main Types of Fire Extinguishers

Different extinguishers are designed to tackle different classes of fire. Using the wrong type can make a fire worse, which is why it’s vital to understand their differences.

Water extinguishers (red label) are designed for Class A fires involving materials such as wood, paper, textiles, or rubbish. They work by cooling the burning material but should never be used on electrical fires or burning liquids.

Foam extinguishers (cream label) are suitable for Class A fires and Class B fires involving flammable liquids such as petrol. They form a blanket that smothers flames and prevents re-ignition. However, they should not be used on electrical fires unless specifically labelled as safe.

CO₂ extinguishers (black label) are primarily used on electrical fires and Class B liquid fires. They work by displacing oxygen to suffocate the flames but are ineffective on solid materials. Care must be taken when handling, as the discharge can cause cold burns.

Dry powder extinguishers (blue label) are highly versatile, tackling Class A, B, and C fires involving solids, liquids, and flammable gases. Specialist powders can also deal with Class D metal fires. While effective, they create a dust cloud that reduces visibility and may damage sensitive equipment.

Wet chemical extinguishers (yellow label) are designed for Class F fires involving cooking oils and fats. They create a cooling, soapy solution that smothers flames and prevents re-ignition. These are essential in commercial kitchens and catering environments.

How to Use a Fire Extinguisher

When tackling a small fire, the PASS method provides a simple, safe approach: Pull the pin to unlock the extinguisher, Aim the nozzle at the base of the fire, Squeeze the handle to release the agent, and Sweep side to side until the flames are out.

It is important to remember that fire extinguishers are only intended for small, manageable fires. If there is any doubt, evacuation should take priority, and the fire service must be called immediately.

Placement Guide: Where Should Extinguishers Go?

Even the right extinguisher is of little use if it cannot be accessed quickly. UK regulations, specifically BS 5306-8, set out requirements for placement and accessibility.

In general, there should be at least two extinguishers per floor, and no one should have to travel more than 30 metres to reach one. Extinguishers should be mounted securely on walls or placed on stands in visible, accessible points — particularly near fire exits, corridors, and high-risk areas such as kitchens, plant rooms, and workshops. Signage must clearly indicate their locations.

Different environments call for tailored placement. Offices typically require a mix of water or foam extinguishers alongside CO₂ units for electrical risks. Kitchens should always have wet chemical extinguishers for cooking oils, while warehouses may need dry powder extinguishers to cover a range of fuel types.

Maintenance and Training

An extinguisher is only effective if it functions correctly when needed. This means regular checks and professional servicing are essential. Monthly visual checks should confirm extinguishers are accessible and undamaged. Annual servicing must be carried out by a qualified engineer, while more thorough extended servicing — including pressure tests — is required every five years for most types.

Equally important is staff training. Building occupants must know not only where extinguishers are located but also how and when to use them safely. Without training, extinguishers may be misused or avoided altogether in an emergency.

Conclusion

Fire extinguishers are a vital first line of defence in any fire safety strategy. Their effectiveness depends on choosing the right type, placing them correctly, and ensuring they are properly maintained. When combined with clear evacuation procedures and well-trained staff, extinguishers can play a crucial role in protecting both people and property from fire.

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