How Many Fire Extinguishers Do I Need in My Building?

March 18 2021

How Many Fire Extinguishers Do I Need in My Building?

Most building owners are aware that fire extinguishers are required in all industrial and commercial buildings according to the National Fire Protection Association NFPA 1: Fire Code. While many building owners, managers, and health and safety specialists are concerned with having the correct amount of fire extinguishers in their buildings, only a fraction of them actually know the exact amount of fire extinguishers required for their specific building.

What is the cause of this discrepancy?

While it would be convenient to have a blanket answer, the reality is that there isn’t a one size fits all approach to this question as each building has different safety parameters. Building owners and managers who understand the factors that determine the number of fire extinguishers needed for their given building will be better positioned to work with a fire protection company to ensure the safety of their facility and employees.

Factors Determining the Necessary Number of Fire Extinguishers

There are several factors that dictate the required number of fire extinguishers for a given building including size of the building, placement and location of fire extinguishers, and fire hazard level.

Occupational Safety and Health Administration (OSHA) standards and building codes apply these factors and conditions when determining the fire extinguisher requirements for a building. The NFPA takes fire extinguisher safety a step further by determining the specific types of fire extinguishers required for each building.

By working with a fire and life safety service provider, building owners and managers can ensure regulatory compliance and most importantly confidently secure the safety of their facility and employees.

Size and Layout of the Building

The square footage of a building and the specific blueprint of the room are key factors in determining the necessary number of fire extinguishers for a given building. According to OSHA standards, portable fire extinguishers are required to be situated with a travel distance of 75 feet or less. Regulatory requirements and the square footage contained in a building will contribute to the final number of fire extinguishers needed.

Fire Hazard Level

In order to fully comprehend the different fire hazard levels, building owners should first be familiar with the five main classes of fire they could encounter. Fires are classified as:

  • Class A: ordinary combustibles
  • Class B: flammable liquids and gas
  • Class C: electrical equipment
  • Class D: combustible metals
  • Class K: cooking oils and grease

A fire hazard level refers to the amount of fire risk that exists in a given building. Commercial and industrial buildings are evaluated and assigned a fire hazard level based on business scope and what the building contains. The assigned fire hazard level is used to determine the right type of fire extinguishers required for a given building. Fire hazard level also determines how closely fire extinguishers of a certain size should be positioned in a workspace. These assigned fire risk assessments are usually categorized as light, ordinary, and extra with commercial kitchens having their own fire class and hazard levels.

Light Fire Hazard: When a building doesn’t contain a high amount of combustible materials, it is classified at the light fire hazard level. A building classified as a light fire hazard will have a minimal quantity of Class A combustibles and Class B flammables. Buildings such as offices, schools, churches, and hotels are examples of buildings with minimal fire risk.

Ordinary Fire Hazard: Ordinary Fire Hazards are classified into two sub-categories: ordinary fire hazards I and ordinary fire hazard II. The first level of ordinary fire hazards includes buildings that pose a slight but negligible fire hazard. These include buildings where the quantity of Class A combustible materials and Class B flammable liquids are moderate. The first tier of Ordinary fire hazards include buildings such as fabric stores, dry cleaners, and post offices. The second tier of ordinary fire hazards are defined as housing more flammable materials in closer proximity than Ordinary Fire Hazards I but not enough of a fire risk to be considered an extra fire hazard. Ordinary Fire Hazard II locations include parking garages, hardware stores, and other buildings where ignition sources may be present.

Extra Fire Hazard: Extra fire hazard occupancies present a greater fire risk than what is considered an “ordinary” amount. A building classified as an extra fire hazard will have a high quantity of Class A combustible material and where higher amounts of Class B flammable liquids are present. Buildings with an increased fire risk such as assembly plants, furniture upholstering services, and die casting facilities are examples of common extra fire hazard buildings due to high quantities of combustible contents, flammable liquids, and ignition sources.

Commercial Kitchens: Commercial kitchens receive their own fire hazard level classification due to the presence of high quantities of Class K combustible material. These materials include cooking oils and grease used on kitchen equipment with large amounts of heat.

Location of Fire Extinguishers

While matching the correct type of fire extinguisher for the correct hazard is essential to securing the safety of facilities and employees, it's only the first step in a larger process. In order to appropriately and accurately access the required number of fire extinguishers needed for a given building, building owners need to work concurrently with a trusted fire and life safety company. Working with a fire and life safety service provider will ensure buildings stay compliant as there are specific fire extinguisher location requirements from OSHA’s Occupational Safety and Health Standards.

By combining information regarding building size and fire hazard level with the placement and location of fire extinguishers, a trusted fire and life safety service provider can implement a tailored protection solution that ensures regulatory compliance and the protection of facilities and employees.

If building owners want to be better prepared to work with a fire and life safety company to implement fire extinguisher services, they should have an understanding of the basic types of portable fire extinguisher ratings. As a reminder, the basic types of portable fire extinguisher ratings are Class A, B, C, D, or K. These ratings, along with the size of the building, the type of fire extinguisher, and the locations of potential hazards play an important role in determining how far apart fire extinguishers need to be from one another and ultimately how many will be required. Here are the locations where each type of extinguisher is required:

Class A: Buildings and locations that contain ordinary combustible materials including offices, classrooms, and assembly halls.
Class B: Buildings and locations that contain flammable liquids or gasses such as workshops, storage areas, and warehouses.
Class C: Buildings and locations where energized electrical equipment is used.
Class D: Buildings and locations that generate metal powders, flakes, or shavings at least once every 1-2 weeks.
Class K: Commercial kitchens or other locations where combustible cooking oils and grease are present.

Placement of Fire Extinguishers

Similarly to location requirements, fire extinguisher placement restrictions are based on the size of the area, the type of fire extinguishers, and the locations of potential hazards. Below is an overview of fire extinguisher placement proximity depending on the hazard type where maximum travel distance refers to the farthest someone should need to travel before reaching another fire extinguisher.

Class A Fire Extinguishers
  • Maximum Travel Distance: 75 feet
Class B Fire Extinguishers
  • Maximum Travel Distance: 50 feet
Class C Fire Extinguishers
  • Maximum Travel Distance: Based on the Class A or B hazard
Class D Fire Extinguishers
  • Maximum Travel Distance: 75 feet
Class K Fire Extinguishers
  • Maximum Travel Distance: 30 feet
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The Right Amount of Fire Extinguishers for Your Building

Understanding all of the factors that go into a building’s fire extinguisher requirements can be daunting. Building owners that have the safety of their facility and employees on the line simply have too much at stake to risk implementing fire extinguisher safety protocols alone.

Building owners that proactively partner with a fire and life safety service provider can discuss their specific building size, fire hazard level, placement, and location of fire extinguishers to create a uniquely tailored fire and life safety protection plan that keeps facilities and employees secure. The right fire and life safety service provider will work lockstep with organizations to confidently navigate NFPA standards, local codes, and OSHA requirements to ensure regulatory compliance.

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