Fire Extinguishers: Types, Uses and Best Practices

For the year ending June 2024, fire and rescue services attended 594,384 incidents in England alone. However, only 129,541 were actually fires (as opposed to non-fire incidents or fire false alarms). This is the lowest record since data became available. A part of this decrease could be down to increased training on fire extinguishers, among other things.  

Fire extinguishers are an essential safety tool, serving as the first line of defence against small fires in homes, workplaces and public spaces. Their proper use can prevent minor incidents from escalating into catastrophic events, safeguarding lives and property. However, not all fire extinguishers are the same and using the wrong type can sometimes make a fire worse.

This article will provide a comprehensive guide to understanding fire extinguishers. It will explore the different types of extinguishers, explain their specific uses and share best practices for maintenance and safety. Whether you’re preparing your home, office or community space, this knowledge is crucial for ensuring you’re equipped to handle potential fire emergencies effectively.

The Science of Fire

Before we can understand fire extinguishers and their uses, it’s important to know about the science of fire. So, what is fire? Fire is a chemical reaction known as combustion, which occurs when heat, fuel and oxygen combine in the right proportions. This relationship is often described as the fire triangle because it needs all three ingredients:

• Heat: The energy needed to ignite and sustain a fire.
• Fuel: Any combustible material, such as wood, paper or flammable liquids.
• Oxygen: A component of air that supports combustion.

Fire extinguishers work by disrupting one or more sides of this triangle. For example:

• Cooling the heat (e.g. water extinguishers).
• Removing oxygen (e.g. carbon dioxide extinguishers).
• Interrupting the fuel supply or chemical reaction (e.g. dry chemical extinguishers).

Understanding the fire triangle is key to knowing how extinguishers combat fires effectively.

Why Choosing the Right Extinguisher is Critical

Not all fires are the same, and using the wrong extinguisher can worsen the situation:

• A water extinguisher on an electrical fire could cause electrocution.
• A CO₂ extinguisher on a grease fire might spread burning oil.

Types of Fire Extinguishers and Their Uses

Fires are categorised into classes (A, B, C, D and K), each requiring a specific type of extinguisher. Choosing the correct extinguisher ensures that the fire is suppressed effectively without causing additional harm or risk. Proper knowledge of fire types and extinguisher classifications is crucial for safety in any environment.

Water Fire Extinguishers (Class A)

These are best for fires involving solid materials like wood, paper and textiles. They’re not suitable for electrical fires, gases or flammable liquids. Water fire extinguishers work by cooling the burning material to extinguish the fire.

Foam Fire Extinguishers (Class A and B)

These are best for fires involving solid combustibles (Class A) and flammable liquids (Class B) like petrol and oil. They’re not suitable for electrical or flammable metal fires.

Foam fire extinguishers work by adding foam that creates a barrier between the fuel and the oxygen, preventing reignition.

CO₂ Fire Extinguishers (Class B and Electrical Fires)

Carbon dioxide fire extinguishers are best for flammable liquid fires (Class B) and electrical fires. They are not suitable for solid materials (Class A fires) or confined spaces. 

Carbon dioxide displaces oxygen and cools the fire, making it ideal for electrical equipment. 

Dry Powder Extinguishers (Class A, B and C Fires)

Dry powder extinguishers are best for fires involving flammable gases (Class C), electrical equipment, flammable liquids and solid materials. They’re not suitable for confined spaces or cooking oils. Essentially, the powder interrupts the chemical reaction in the fire and provides a barrier between the fuel and the oxygen.

Wet Chemical Fire Extinguishers (Class F)

These are best for fires involving cooking oils and fats and are typically used in kitchens. They’re not suitable for any other types of fires. These work by cooling the fire and creating a layer that prevents reignition. 

How to Use a Fire Extinguisher (The PASS Method)

For ease of memory, the acronym PASS is used to remind people how to use a fire extinguisher. PASS stands for:

• PULL the pin to break the tamper seal.
• AIM low at the base of the fire.
• SQUEEZE the handle to release the extinguishing agent.
• SWEEP the nozzle from side to side, covering the fire evenly.

When to Use a Fire Extinguisher

Fire extinguishers are essential tools for controlling small, manageable fires but it is critical to understand their limitations and when they should be used.

When to Act

Fire extinguishers are most effective in the early stages of a fire before it spreads or grows uncontrollably. 

Consider using a fire extinguisher only if:

• The fire is small and contained, such as in a wastepaper bin or on a cooker top.
• You have a clear escape route, ensuring you won’t be trapped if the fire intensifies.
• The extinguisher is appropriate for the fire type, and you have been trained in its use.

When to Evacuate

If the fire is too large, spreading quickly or producing thick smoke, attempting to extinguish it can be dangerous. Instead:

• Evacuate immediately, ensuring everyone in the area is safely out.
• Close doors behind you to slow the spread of the fire.
• Call emergency services to handle the situation professionally.

Fire extinguishers are a first response, not a substitute for professional firefighting resources. Prioritise your safety and others’ well-being above all else.

Best Practices for Fire Extinguisher Maintenance and Safety

Proper maintenance and understanding of fire extinguishers are vital to ensuring they function effectively when needed. 

Follow these best practices to maintain and use fire extinguishers safely:

Regular Inspections

You should aim to check your fire extinguishers regularly. This should be a mixture of monthly checks alongside annual professional maintenance.

Monthly Checks

1. Inspect the extinguisher to ensure it is in its designated location, unblocked and easy to access.
2. Check the pressure gauge to ensure the needle is in the green zone, indicating adequate pressure.
3. Confirm that the safety pin is intact and the exterior is free from damage, corrosion or leaks.

Annual Professional Maintenance

Have the extinguisher inspected and serviced by a qualified technician at least once a year. Professionals will verify its functionality, refill or recharge as necessary and certify compliance with safety standards.

Proper Storage

Fire extinguishers need to be stored properly. This means being accessible and visible. You should place extinguishers in locations prone to fire risks, such as kitchens, garages or near exits. They need to be easy to access in an emergency and free from obstructions or barriers.

In terms of visibility, use clear signage to mark extinguisher locations, especially in workplaces or public spaces, and position extinguishers at eye level or within reach to ensure quick identification and use.

Training

Anyone who may need to use a fire extinguisher should be trained on how to do so. This means educating household members, employees or staff on how to use the PASS method (Pull, Aim, Squeeze, Sweep) for effective extinguisher use.

For the workplace, training should involve practice or safety drills that build confidence of use enough to use the equipment during an actual emergency.

Alongside training for fire extinguishers, there needs to be a clear evacuation plan that prioritises safety before fire suppression. Fire drills should be a regular occurrence so that everyone knows how to exist safely in case a fire becomes unmanageable.

Fire Extinguisher Regulations and Compliance

Fire extinguishers are not only essential safety tools but are also subject to various regulations to ensure they are available and effective when needed. Understanding these requirements is crucial for both homeowners and business owners.

Regulations for Homeowners

While not universally mandatory, many local fire safety laws recommend or require fire extinguishers in residential properties.

• Building Codes: Some jurisdictions include fire extinguisher placement in their building codes, particularly in areas prone to fire hazards like kitchens or garages.
• Home Insurance Requirements: Insurance providers may offer incentives or discounts to homeowners who comply with fire safety measures, including keeping fire extinguishers readily available.
• Smoke and Fire Prevention Campaigns: Fire departments often encourage homeowners to install and maintain extinguishers as part of broader safety initiatives.

Business Requirements

For businesses, fire extinguisher compliance is a legal necessity, ensuring safety for employees, customers, and the property itself.

The Fire Safety Regulations (2022) set out requirements for certain types of buildings. After the Grenfell Tower Inquiry Phase 1 report, which required a change in the law, anyone responsible for high-rise blocks of flats must provide information to Fire and Rescue services to assist them to plan and provide a response in the case of a fire. They are required to provide:

• Building plans
• Locations of key firefighting equipment
• Information about the design and materials of the external walls (and the level of risk)
• Reports of defective lifts as soon as possible if faults can’t be fixed within 24 hours
• Secure information boxes in the building with hard copies of building floor plans
• Visible signage for low light and smoky conditions
• Safety instructions to residents

Penalties for Non-Compliance

Failure to adhere to fire extinguisher regulations can lead to fines, legal action or increased liability in the event of a fire. For businesses, ensuring compliance also demonstrates a commitment to employee and customer safety.

Understanding and meeting these regulatory requirements ensures that fire extinguishers are not only present but also ready to save lives and property in emergencies.

Common Fire Extinguisher Mistakes and How to Avoid Them

Fire extinguishers are vital safety tools, but their effectiveness relies on proper usage, maintenance and understanding of their limitations. Missteps during an emergency can lead to severe consequences, including the escalation of the fire or unnecessary risks. 

Below are common fire extinguisher mistakes and actionable steps to avoid them.

Using the Wrong Extinguisher

Each type of fire extinguisher is designed to combat specific classes of fire:

• Water extinguishers are effective for Class A fires (solid combustibles like wood or paper) but dangerous for electrical fires.
• CO₂ extinguishers are ideal for electrical fires but ineffective on flammable metals or cooking oil fires.
• Foam or powder extinguishers can handle a range of fires but may damage sensitive equipment or leave residues that are difficult to clean.

Why It Matters: Using the wrong extinguisher can worsen the fire. For example, spraying water on an oil fire can cause the flames to spread, while using a foam extinguisher on an electrical fire could result in electrocution.

How to Avoid This Mistake

• Learn the classes of fire and the corresponding extinguishers. Many extinguishers are labelled with clear icons or text indicating their intended use.
• Conduct training sessions that include identifying the right extinguisher for different scenarios.
• Place extinguishers strategically, ensuring the type matches the fire risks in that area (e.g. a CO₂ extinguisher in offices, wet chemical extinguishers in kitchens).

Not Knowing How to Operate a Fire Extinguisher

Many people hesitate or struggle to use a fire extinguisher during emergencies due to unfamiliarity or fear.

Why It Matters: In an emergency, hesitation or incorrect operation can allow the fire to grow uncontrollably. For instance, failing to aim at the fire’s base rather than its flames renders extinguishing efforts ineffective.

How to Avoid This Mistake

• Practise the PASS Method:
  1. Pull the pin to break the tamper seal.
  2. Aim low, at the base of the fire.
  3. Squeeze the handle to release the extinguishing agent.
  4. Sweep the nozzle side to side across the base until the fire is out.
• Conduct regular hands-on training for staff or household members using decommissioned or demonstration extinguishers.
• Include fire extinguisher tutorials in workplace safety orientations and community fire safety workshops.

Neglecting Maintenance

Fire extinguishers are often left unchecked for years, only to fail during emergencies due to leaks, low pressure or internal corrosion.

Why It Matters: A neglected extinguisher may be ineffective or completely non-functional when needed. Common maintenance issues include:

• Pressure gauge in the ‘red zone’, indicating insufficient pressure to release the extinguishing agent.
• Blocked or corroded nozzles that prevent proper spray.
• Expired extinguishers that have surpassed their functional lifespan.

How to Avoid This Mistake

• Monthly Inspections: Check extinguishers for visible signs of damage, ensure the pressure gauge is in the green zone, and confirm accessibility.
• Annual Maintenance: Hire a certified technician to perform a thorough inspection, refill extinguishers if necessary, and replace any damaged units.
• Scheduled Replacement: Replace extinguishers every 5–15 years (depending on type and manufacturer recommendations). Clearly mark expiration dates for easy tracking.

By avoiding these common mistakes, individuals and organisations can maximise the effectiveness of fire extinguishers, ensuring a safer environment and a more confident response during emergencies.

Conclusion

Fire extinguishers play a crucial role in fire safety, serving as the first line of defence against small fires that could otherwise escalate into catastrophic events. Understanding the different types of extinguishers, knowing when and how to use them and adhering to best practices for maintenance are essential steps in ensuring safety at home, in the workplace and in public spaces.

Proper knowledge and preparedness can save lives, protect property and significantly reduce risks during emergencies. By taking the time to familiarise yourself with fire extinguisher types, regularly inspecting and maintaining them, and training household members or staff, you can enhance your ability to respond effectively to a fire.

Take action today: Assess your current fire safety equipment, ensure it is suitable for your environment, and provide the necessary training to those around you. Prioritise fire safety as an ongoing commitment to protect your loved ones, your property and your peace of mind.