What Are Commercial Fire Extinguisher Ratings?

Do you know which commercial grade fire extinguisher is essential for protecting your commercial building in a fire emergency? If you need help, you’re in the right place! Being aware of each fire extinguisher’s types and ratings can help ensure safety and proper usage when needed. In this blog post, we will discuss commercial grade fire extinguisher ratings to help you figure out which one is right for your situation. Let’s do it!


What Are Commercial Fire Extinguisher Ratings?


Commercial fire extinguisher ratings are a way to classify their effectiveness against certain types of fires. You’ll see them as a letter followed by a number outlining which fire can extinguish. 


The letters denote the type of combustible material that the extinguisher can put out effectively. At the same time, the number describes how large and concentrated the fire can be before becoming uncontrollable.


Knowing a fire extinguisher’s rating gives you an idea of its ability to put out fires safely and quickly. This is why it’s so important to purchase one with the appropriate rating for your intended purpose.


What Do the Letters Mean in Commercial Fire Extinguisher Ratings?


The letters in commercial fire extinguisher ratings categorize fire extinguishers based on the type of materials they can extinguish effectively. For example:


  • Class A ratings are for common combustible materials. These include wood, paper, cloth, rubber, and plastic.
  • Class B ratings refer to fires fueled by flammable liquids, such as gasoline or kerosene.
  • Class C fires are related to electrical equipment.
  • Class D are for combustible metals
  • Class K ratings indicate that the fire extinguisher will work on kitchen fires caused by combustible oils and fats.


What Do the Numbers Mean in Commercial Fire Extinguisher Ratings?


The ratings are made up of two numbers that provide a variety of key pieces of information about the extinguisher. The first number relates to the square footage it will cover, with higher coverage ratings indicating that the extinguisher can cover a larger area in an emergency. The second number is associated with the fire suppression class. This is according to a predetermined standard outlined by NFPA for specific types of fires most commonly encountered in commercial buildings.


  • A commercial fire extinguisher with a rating of 2A:10B: C means it is suitable for use on Class A, Class B, and Class C fires. The first number (2A) indicates how much water it holds; 10B means it can discharge 10 square feet of burning material; and C tells you it will work against electrical-based fires.


  • A commercial rating of 4A: 80BC indicates the capability of an extinguisher to handle different types of fires. In this rating, 4A stands for the amount of water-based fire intensity approved to be put out, and 80BC is for pressurized dry chemical types. 4A: 80BC on a fire extinguisher tells us that it contains 16.5kg (4.5 gallons) of water and can put out a fire over an area of 80 sq. ft. 


The lower the rating, the less firefighting power a commercial fire extinguisher has. Understanding these ratings can help minimize damages and save lives in an emergency.




In conclusion, the different commercial fire extinguisher ratings are the standard for determining what type of fire extinguisher you should use in specific locations. It is important to know the ratings of each type of fire extinguisher one could use since they vary greatly from one to another.


Do your commercial fire extinguishers need servicing? If so, you’ve come to the right place! Click here to get in touch with Fire-Alert, and get started with us today.