Mercury Fire and Security

When and How To Use a Fire Extinguisher: A Complete Safety Guide

Fire extinguishers are one of the most essential pieces of safety equipment in any home, workplace, school, or public building. But owning one isn’t enough, you must know when you should use a fire extinguisher and how to use a fire extinguisher correctly, confidently, and safely. At Mercury Security, we’ve supplied, maintained and inspected fire safety equipment across the UK for decades. This guide explains everything you need to know to ensure you’re prepared in an emergency.


When Should You Use a Fire Extinguisher?

Knowing when to act is just as important as knowing how. You should only attempt to use a fire extinguisher if the fire is small and contained, such as a minor waste bin fire or a small kitchen flare-up, and you can clearly see the source of the flames. It’s crucial that you have a clear and unobstructed escape route behind you so that you can retreat safely if the situation changes. Before using an extinguisher, make sure you have identified the type of fire and are using the correct extinguisher for it. Finally, only proceed if you feel confident, capable, and have at least a basic understanding of how to use the equipment.

However, there are also situations where you should not try to use a fire extinguisher. If the fire is large, spreading, or producing a significant amount of smoke, it is far safer to evacuate immediately. The same applies if you are unsure what caused the fire, if you do not have the correct type of extinguisher, or if flammable gas cylinders or unidentified chemicals are involved. Most importantly, if at any point you feel unsafe, untrained, or unsure, you should leave the area and call 999 without attempting to fight the fire yourself.


How to Use a Fire Extinguisher (The PASS Technique)

Once you’ve judged that it’s safe to act, follow the internationally recognised PASS method. This simple technique is the gold standard for teaching people how to use a fire extinguisher correctly.


P – Pull the pin

This unlocks the handle and allows you to discharge the extinguisher.

A – Aim at the base of the fire

Never aim at the flames. Target the base where the fuel source is.

S – Squeeze the handle

Press the handles together firmly to release the extinguishing agent.

S – Sweep from side to side

Move in slow, controlled motions, covering the base until the fire is fully out.


Important: Always keep your escape route behind you. If the fire grows or you feel overwhelmed, evacuate immediately.


Choosing the Right Type of Fire Extinguisher

Using the wrong extinguisher can make a fire worse. Here’s our guide. If you’re still unsure which extinguishers your premises need, Mercury Security can provide full assessments, installations and maintenance packages.


Safety Tips Before Using a Fire Extinguisher

  • Alert others and raise the alarm
  • Call emergency services, even if the fire seems small
  • Avoid inhaling smoke
  • Stay calm and think clearly
  • Never turn your back on a fire
  • After any use, even a test, an extinguisher must be professionally recharged or replaced

After the Fire: What Happens Next?

  • Evacuate and wait for emergency services to confirm it’s safe to return
  • Do not attempt to clean up chemical residue without proper protection
  • Arrange for your extinguishers to be inspected, replaced, or refilled
  • Consider a full fire safety review to prevent future incidents

Mercury Security provides comprehensive fire extinguisher servicing, checks and replacements across the UK to keep your building fully compliant and safe.

Understanding when you should use a fire extinguisher and how to use a fire extinguisher could save lives. With the right training and equipment, small fires can be controlled quickly, without putting yourself or others at unnecessary risk.

For expert guidance, professional fire extinguisher installation, or scheduled maintenance, contact Mercury Security today. Our specialists ensure your business meets all UK fire safety regulations and remains fully protected.