What are Class B foams used for?

Class B Foam (also called AFFF): Used to extinguish Class B materials, which include gasoline, oil, and jet fuel.

Can you mix Class A and Class B foam?

Class A and Class B foam should never be applied simultaneously or on top of one another. While mixing foams during foam application on scenes can render an operation ineffective, mixing foams in storage can cause the foam to degrade and become ineffective when used.

What is a benefit to using Class A foam?

Advantages of Class A foam

The key advantage of Class A foam is that it significantly enhances water's effectiveness in putting out flames. Water's strong surface tension causes it to bead up and roll off most fuels and away from heat too quickly for the fuel to be able to absorb the water's full heat capacity.

What foam do firefighters use?

Firefighters use aqueous film-forming foam (AFFF) to help extinguish difficult-to-fight fires, particularly fires that involve petroleum or other flammable liquids ‚ known as Class B fires. However, not all firefighting foams are classified as AFFF.

Why are Class B foams effective on fires that are fueled by liquid hydrocarbons?

ANSUL® Class B Foam Agents are the ideal fire suppression choice for fires involving flammable and combustible liquids. These agents suppress fire by blocking oxygen supply to the fuel, suppressing fuel vapors and providing a cooling effect.

Module 6: Fire Fighting Foam Principles

Is Class B foam the same as AFFF?

Class B Foam (also called AFFF): Used to extinguish Class B materials, which include gasoline, oil, and jet fuel.

What is class B foam made of?

Class B foams can be protein foams or synthetic foams. Protein foams contain natural proteins and are generally biodegradable; synthetic foams are made of synthetic foaming agents.

What is Class A firefighting foam?

Class A foams are used to extinguish fires caused by wood, paper, and brush. Class A foams generally do not contain per- and polyfluoroalkyl substances (also known as “PFAS”).

When using foam a Class B fire is extinguished by?

Foam extinguishes Class B Fires by covering the flammable liquid with a foam blanket, thus cutting off the oxygen supply from the combustion process. The water content of the foam will help lower the temperature of the flammable liquid.

Does Class B foam contain PFAS?

The vast majority of the Class B fire- fighting foam in stock or service in the United States is aqueous film-forming foam (AFFF) or alcohol-resistant aque- ous film-forming foam (AR-AFFF). 1 These foams contain PFAS. Class B foams that are fluorine-free do NOT contain PFAS.

When should I use foam firefighting?

Class 'B' foam is used for Class 'B' fires, which are fires that involve flammable liquids such as alcohol, ether, oil, gasoline or grease. Class 'B' fires are best extinguished by smothering or applying a blanket of Class 'B' foam, which is meant to float on the surface of burning fluid.

Does Class A foam expire?

The effective life of CLASS A PLUS foam concentrate can be maximized through optimal storage conditions and proper handling. CHEMGUARD concentrates have demonstrated effective firefighting performance with contents stored in the original package under proper conditions for more than 10 years.

What type of foam clings to vertical surfaces?

The expanded foam solutions also create a dense foam blanket that clings to vertical surfaces and provides an insulating barrier between the fuel and the air. Chemical Foam has been classified in different ways over the years.

Can you use Class B foam on Class A fires?

By increasing your knowledge about the two different types of foam, you'll be confident in knowing when, where and how to use Class A and Class B foam to achieve fast, safe suppression for any type of fire situation. It's obvious that Class A foam is used to fight Class A fires, and that Class B foam snuffs out the Bs.

What is an advantage of compressed air foam?

Compressed air foam provides quicker knockdown times and minimizes FF exposure to immediately dangerous to life and health (IDLH) environments. The increased drain time of the CAFS allows water to be used more effectively while fire fighting. Due to its high-surface tension, water tends to run off of surfaces.

What is the difference between AFFF and AR AFFF?

AFFF and AR-AFFF consist of essentially the same ingredients. These typically include fluorosurfactants, hydrocarbon surfactants, solvents, inorganic salts, corrosion inhibitors, water; and in the case of AR- AFFF, a polymer which is typically a polysaccharide.

What is Class B fire extinguisher used for?

Class B: Flammable liquids such as alcohol, ether, oil, gasoline and grease, which are best extinguished by smothering. Class C: Electrical equipment, appliances and wiring in which the use or a nonconductive extinguishing agent prevents injury from electrical shock.

What is a Class B material?

In fire classes, a Class B fire is a fire in flammable liquids or flammable gases, petroleum greases, tars, oils, oil-based paints, solvents, lacquers, or alcohols. For example, propane, natural gas, gasoline and kerosene fires are types of Class B fires.

What type of fire requires a Class B fire extinguisher?

Class B - Fires involving flammable liquids, gases, oil, paints, or lacquer.

What is Class C fire?

Class C. Class C fires involve energized electrical equipment. Extinguishers with a C rating are designed for use with fires involving energized electrical equipment.

Why do firefighters use foam instead of water?

Class A foams are used to lessen the surface tension of water, which improves the wetting and saturation of water used to fight Class A fires, which are fueled by ordinary combustibles.

Is high expansion foam to fight a fire on deck?

If we use high expansion foam for deck fires, the foam will fly with the wind and will not be able to extinguish the fire. For this reason, for deck fires low expansion foam is used. On tankers, it will always be low expansion foam for fires of the cargo area.

Is AFFF still being used?

AFFF is still in use today. Flash forward to 2020, and we now know that the same chemicals that give these firefighting foams their unique properties have become a major global source of drinking water contamination.

Is AFFF foam banned?

The military plans to phase out the use of firefighting foam containing PFOAs by October 2024, as directed in the National Defense Authorization Act of 2020. However, this deadline is still two and a half years away, leaving little protection for the people who are exposed in the meantime.