US Fire Testing Class B


What is a Class B fire?

Fire class is a term used to denote the type of fire in relation to the combustion material which has ignited. A Class B fire is described as flammable liquids & gases such as Gasoline, Diesel, Paint, Kerosene, Adhesives etc.

All Firexo Fire Class ratings have been achieved through the EN fire tests.


US Fire Testing Class B
US Fire Testing Class B

Class B fire rating explained:

When testing an extinguisher against a class B fire, there are 10 different sizes of fire that can be attempted. These different difficulty levels are set up to distinguish what size of fire the extinguisher can handle. These difficulty levels are as follows; 13B, 21B, 34B, 55B, 70B, 89B, 113B, 144B, 183B, and 233B. The number of the fire test is the total amount of liters in the fuel tray, so a 13B fire is 13 liters, whilst a 233B is 233 liters.

A class B test consists of varying sizes of trays and the amount of liquid contained inside each tray is split into two parts: two parts heptane to every one-part water. So, for example a fire rating of 21B would have 7 liters of water and 14 liters (7+14=21B) of heptane in a round tray.

The size of the tray increases as the fire rating increases, so a 233B fire will be carried out in a tray that has a diameter of 3 meters, whereas a 13B fire will be 0.72 cm.

Once the water and heptane have been added the fire is lit and allowed to burn for 2 minutes, the fire fighter is then sent into the fire with a single extinguisher and allowed to extinguish the fire at their discretion. In order to pass the test, there must be no flames left in the entire structure at the end.

You are allowed 3 tests and the extinguisher must pass two of the three to be deemed successful for a class B rating.

In the U.S. the fire tests, as detailed in UL7111, are very similar for all classes of fire but there are subtle differences such as the height of the Class A crib, shape of the Class B tray, or the number of liters required for Class K. Firexo is currently undertaking the UL Certification and Approval process and hopes to achieve UL Listing as early as Q1 2021. Please watch this space because we will be updating it to the show the UL fire tests as they are achieved, demonstrating why Firexo is the most effective fire fighting media on the market today.



Available sizes:

 Compact0.5gal 1.5gal2.5 gal

Fire test guidelines are designed to be several times the magnitude of anything the extinguisher would be expected to tackle in the real world.