Extinguish any type of fire – fast!

What is a Class B fire?
Class B includes fires involving flammable or combustible liquids. This group includes petrol, oils, alcohols, paints and solvents. Class B fires are characterised by that the fire spreading very quickly across the surface of the liquid. This makes them particularly dangerous and more difficult to control than fires involving solid materials.

What are Class B tests?
Under the EN 3-7 standard, Class B extinguisher tests involve 10 levels (13B–233B) based on fuel volume. Trays contain 1/3 water and 2/3 heptane. After a 2-minute pre-burn, a firefighter must fully extinguish the flames. To pass, the extinguisher must succeed in 2 out of 3 attempts for a specific rating.

What is a Class C fire?
Class C fires involve flammable gases such as propane, butane, methane, and hydrogen. Under the EN 3-7 standard, this class has no numerical rating; an extinguisher is either certified for gas or not.

The current testing system under EN 3-7 systematically reserves the Class C rating for powder-based extinguishers. Because Firexo is an innovative water-based solution, existing regulations do not allow it to be formally certified for this class. Capability tests show Firexo’s extinguishers are highly effective at extinguishing gas fires, even though they don’t have an official Class C mark.

What are Class C tests?
Class C tests involve extinguishing a burning propane flame emerging under a pressure of at least 5 bar through a 7 mm nozzle. The apparatus consists of a 2-metre horizontal pipe. To pass, the flame must be completely extinguished. Up to 6 kg powder-based fire extinguishers must pass 2 out of 3 tests (one extinguisher per test). Fire extinguishers must extinguish two consecutive fires using a single extinguisher. A positive result (2/3 tests) grants the fire extinguisher Class C certification.

What is a Class D fire?
Class D covers fires involving combustible metals such as magnesium, sodium, potassium, lithium, aluminium, and titanium. These are among the most difficult fires to control due to the extremely high combustion temperatures (often exceeding 2,000°C).

What are Class D tests?
In accordance with European testing guidelines, the Class D test uses a tray measuring 50 x 50 x 10 cm, filled with magnesium shavings and 2 litres of heptane. After a 20-minute initial burning period, a firefighter must extinguish the fire. The test is considered successful if no visible flames are observed after a 20-minute observation period. Additionally, an internal inspection must show that hot spots cover less than 10% of the surface and do not spread. This demonstrates the agent’s ability to cool and stabilise reactive metals.

What are electrical fires?
Fires involving live electrical equipment are defined as fires in other categories (usually A and B) in which electricity acts as the initiating source rather than fuel.

A special 35 kV dielectric laboratory test determines the suitability of a fire extinguisher.

What is a 35 kV dielectric test?
The 35 kV dielectric test is a safety benchmark under the EN 3-7 standard. It ensures an extinguisher is safe for use on live electrical equipment. During the test, 35,000 volts are applied to a metal plate, and the extinguisher’s stream is directed at it from 1 m.

To pass, the electrical leakage through the stream must not exceed 0.5 mA. While the test uses 35 kV, the certified safe limit for users is 1,000 V at 1 m, providing a substantial safety margin against shocks.

What is fire Class F?
Class F fires involve cooking media such as vegetable or animal oils and fats. They typically occur in kitchens, specifically in deep fryers or large frying pans. Although they involve liquids, they are classified separately from Class B fires due to their exceptionally high operating temperatures and specific chemical properties.

What are Class F tests?
Under the EN 3-7 standard, Class F extinguisher tests evaluate performance against cooking oil fires across five levels (3F to 75F), representing the litres of oil used. The vegetable oil is heated until self-ignition, followed by a 2-minute pre-burn. A firefighter must then extinguish the flames in a single continuous action.

To pass, there must be no visible flames, and the oil is monitored for 20 minutes to ensure no re-ignition occurs. Success requires passing two out of three attempts for a specific rating.

Lithium-ion batteries are widely used in consumer electronics, e-bikes, power tools, and electric vehicles. When they fail, they can enter a process known as thermal runaway – a rapid and self-sustaining increase in temperature.

Currently, there is no dedicated international fire classification or standardised extinguisher test specifically for lithium-ion battery fires. In this regard, the Research Institutes of Sweden (RISE) developed an independent testing programme to evaluate Firexo performance.

For testing purposes, Firexo provided three Firexo 9-litre fire extinguishers to RISE alongside the lithium cells – Device Under Test (DUT). Two extinguishers were utilised to test battery fire suppression, whilst the third was used to verify functionality and discharge direction. The testing was conducted across two scenarios: single-cell and multi-cell configurations, comprising one prismatic cell and a larger bank of cylindrical cells.

In the single-cell scenario, the extinguisher successfully reduced the severity of the battery fire. The initial jet flame was extinguished, and subsequent jet flames were significantly reduced in intensity. Importantly, the fire did not re-ignite after the extinguisher had been fully discharged.

In the second scenario, involving a small battery pack, the extinguisher suppressed the initial fire and prevented propagating thermal runaway between cells. This demonstrated the agent’s ability not only to suppress visible flames but also to limit internal heat escalation.

These independently witnessed tests demonstrate that Firexo fire extinguishing liquid effectively suppresses lithium-ion battery fires primarily through rapid cooling, significantly reducing the risk of re-ignition.