Portable fire extinguishers - things you should know


By: Michael Harding 

Properly working portable fire extinguishers are an important safety component for every business. Fire extinguishers are important because they can protect your employees and building in the case of a fire. They are an integral part of a fire safety plan. Correctly placed and maintained extinguishers can help put out or slow down the spread of a fire, giving the people inside more time to escape and limiting property damage.  

Your fire safety plan should emphasize foremost the importance of first notifying all other occupants so they can evacuate and then notifying the fire department. Only after notifying other occupants and the fire department should anyone employ the use of fire extinguishers. But not all fire extinguishers are the same.  

Do you know if you have the correct fire extinguishers for your business? Properly selecting and strategically placing and mounting your fire extinguishers is very important. After you’ve installed them, it’s also essential they are carefully inspected on a regular basis and your employees are trained in their correct use. 

Portable fire extinguisher types 

     Class A  

  • Most common  
  • Labeled by a green triangle encircling the letter “A” 
  • Used on ordinary combustible materials such as cloth, wood, rubber, paper, and many plastics 
  • Uses water to cool and quench the fire 

     Class B  

  • Labeled by a red square encircling the letter “B” 
  • Used on fires involving flammable liquids such as grease, gasoline, oil, and oil-based paints, solvents, and tar 
  • Uses either dry carbon dioxide, chemicals, or foam to smother the fire 

     Class C  

  • Labeled by a blue circle encircling the letter “C” 
  • Used on fires involving appliances, tools, electric panels, transformers, boxes, or other equipment that is electrically energized or plugged in 
  • Uses materials that are non-conductive such as carbon dioxide or dry chemicals to smother the fire 

    Class D

  • Labeled by a yellow five pointed star encircling the letter “D” 
  • Used on flammable metals such as magnesium, aluminum, and titanium. Typically found only in factories working with these metals 
  • Uses dry powders specifically designed to extinguish the relevant combustible metal 

    Class K  

  • Labeled by the letter “K” 
  • Used on fires involving vegetable oils, animal oils, or fats used in cooking appliances. Generally used in commercial kitchens such cafeterias, restaurants, and by caterers 
  • Uses special extinguishing agents to smother the fire 

Multi-purpose fire extinguishers  

  • Vary by type and often include those labeled “B-C” or “A-B-C” 
  • Can be used on two or more of the above type fires  

Take simple steps to prevent fires 

Taking simple steps to prevent fires can go a long way, and you should encourage everyone to help prevent fires by following steps such as these from the National Fire Prevention Association, www.nfpa.org

  • Keep exits clear of trash, storage, cleaning supplies, and other combustibles. 
  • Don’t stack papers on top of computer monitors or other heat-producing equipment – give the equipment room to breathe. 
  • Maintain a policy of use for personal or portable heating devices. 
  • Report blocked exits as well as problems with alarms, public address systems, sprinklers, and emergency lighting. Remind your employees that a chirping fire alarm indicates a new battery is needed; do not disconnect it. Hold employees accountable for changing the battery. 
  • Report and replace frayed electrical cords. 
  • Don’t run electrical cords under furniture and don’t plug extension cords into each other. 
  • Unplug coffeemakers and other appliances when you leave. 
  • Smoke only in designated areas and use the ashtrays. 

Where to install fire extinguishers 

Where you should install your portable fire extinguishers can vary greatly and depend on the type of fire you are likely to have as well as the size and intended use of the extinguisher. According to OSHA, the maximum distance a fire extinguisher should be away from a potential fire is 75 feet. The distribution of portable fire extinguishers is often a balance of having an extinguisher nearby when it’s needed but not being overly burdened by the cost and regular maintenance of having excessive extinguishers. 

The term “maximum travel distance to extinguisher” is often used when addressing fire extinguisher placement. This means that at any point inside the building you should never have to travel more than the maximum distance to reach an extinguisher. It is important to ensure the distance being measured is the actual distance a person would need to walk to get the extinguisher and that occupants are not expected to walk through walls. 


Extinguishers need to be located along normal paths of travel. This is because extinguishers should be available to occupants when evacuating. You do not want occupants to move away from an exit and risk being trapped by the fire when trying to retrieve an extinguisher. Every fire extinguisher must be placed in a visible and easy-to-reach location with the label facing out. They should be installed along hallways, in meeting rooms, near exit doors, and in other common locations. Where visibility is obstructed, visual aids must be provided. With the exception of wheeled fire extinguishers, they cannot be left standing on the floor or on a table – they must be mounted.  

Installation height 

Extinguishers need to be installed at least four inches off the ground up to a maximum of five feet. The exception to this is for extinguishers heavier than 40 pounds, which can only be up to three feet six inches off the ground, and wheeled fire extinguishers, which don’t need to be off the ground since the wheels already keep the cylinder from touching the floor. 


In order for your employees to help put out a fire with an extinguisher, it’s important to train your employees to use this potentially life-saving equipment, ensuring that they can react confidently in case of a fire emergency. To do this, it’s best to provide an educational program so your employees are familiar with the basics of how to use a fire extinguisher and the hazards involved with early-stage fires and fire-fighting. 

OSHA does not require any hands-on training. Training can include online fire extinguisher courses, safety videos, toolbox talks, and even instructional brochures. Employers can use a variety of methods to provide employees with this vital information. Even better, hands-on training should be included for increased effectiveness.  

At a minimum, this hands-on training must include how to discharge a fire extinguisher relevant to the type of fire(s) anticipated. Consider contacting your local fire department or your fire extinguisher provider to provide this training. 

This training should occur initially when the employee is hired and annually thereafter. 

The United States Fire Administration (USFA) recommends that only those trained in the proper use and maintenance of fire extinguishers consider using them when appropriate. 

They advise to use a fire extinguisher only if: 

  • You have alerted other occupants and someone has called the fire department; 
  • The fire is small and contained to a single object, such as a wastebasket; 
  • You are safe from any toxic smoke produced by the fire; 
  • You have a means of escape identified and the fire is not between you and the escape route; and 
  • Your instincts tell you that it is safe to use an extinguisher. 

If all of these conditions are not present, you should NOT try to use a fire extinguisher.  


Fire extinguisher distribution and placement is often the trickiest part of installation. There is a balance between efficiency and practicality that truly make a difference in the event of an emergency.  

You may want to consider working with a fire extinguisher service provider to help you properly place your extinguisher to best protect your property and train your employees. Your employees and your business will benefit from it. 










This "document” is intended for general information purposes and should not be construed as advice or opinions on any specific facts or circumstances. The content of this document is made available on an “as is” basis, without warranty of any kind. This document cannot be assumed to contain every acceptable safety and compliance procedure or that additional procedures might not be appropriate under the circumstances. Markel does not guarantee that this information is or can be relied on for compliance with any law or regulation, assurance against preventable losses, or freedom from legal liability. This publication is not intended to be legal, underwriting, or any other type of professional or technical advice. Persons requiring advice should consult an independent adviser or trained professional. Markel does not guarantee any particular outcome and makes no commitment to update any information herein, or remove any items that are no longer accurate or complete. Furthermore, Markel does not assume any liability to any person or organization for loss or damage caused by or resulting from any reliance placed on this content.

Markel® is a registered trademark of Markel Group Inc.  

© 2023 Markel Service, Incorporated. All rights reserved.

Was this helpful?