Aqueous Film Forming Foam (AFFF) stands as a frontline defence against flammable liquid fires, renowned for its rapid extinguishing capabilities. 

In this article, we explore the complete facts surrounding AFFF, shedding light on its composition, applications, benefits, and drawbacks. 

Understanding the nuances of AFFF is essential for firefighters, industrial facilities, and anyone concerned with fire safety. 

Join us as we delve into the world of Aqueous Film Forming Foam to uncover its role in modern fire suppression and the alternatives available in the firefighting arsenal.

What is Aqueous Film Forming Foam?

Aqueous Film Forming Foam is a firefighting agent utilised to extinguish fires involving flammable liquids. 

It comprises a mixture of water, fluorosurfactants, and hydrocarbon surfactants. 

The key component of AFFF is its ability to form a thin, heat-resistant film on the surface of flammable liquids, effectively smothering the fire and preventing re-ignition. 

This foam blanket cools the fire, suppressing vapour release and preventing oxygen from reaching the fuel source. 

Aqueous Film Forming Foam is typically stored as a concentrate and mixed with water before use, either through a fixed foam system or portable fire fighting equipment such as fire hoses or foam sprayers.

What is Aqueous Film Forming Foam Used for?

Aqueous Film Forming Foam finds extensive use in fire suppression scenarios involving flammable liquid fires. 

Its effectiveness lies in its ability to rapidly extinguish fires fueled by substances such as oil, gasoline, diesel, and solvents. 

AFFF is commonly deployed in various industries, including petrochemical plants, refineries, chemical manufacturing facilities, airports, military installations, and firefighting operations.

Industrial Use

In industrial settings, such as warehouses, Aqueous Film Forming Foam is often integrated into fixed foam systems, providing continuous fire protection for high-risk areas such as storage tanks, loading racks, and process areas. 

These systems can automatically release AFFF when a fire is detected, quickly smothering the flames and preventing escalation.

Aviation Use

In aviation, Aqueous Film Forming Foam is utilised as a firefighting agent for extinguishing fuel fires that may occur during aircraft accidents or emergencies. 

Aircraft rescue and firefighting (ARFF) vehicles are equipped with AFFF-based foam systems capable of delivering large volumes of foam to suppress fires on runways and aircraft surfaces.

Military Use

Similarly, Aqueous Film Forming Foam plays a crucial role in military firefighting operations, where it is used to combat fires on military vehicles, aircraft, and naval vessels. 

Military-grade AFFF formulations are designed to meet stringent performance standards and withstand harsh operational environments.

Emergency Responder Use

In addition to industrial and military applications, AFFF is also employed by municipal fire departments and emergency responders as a portable fire fighting agent. 

Firefighters use AFFF-based foam solutions to extinguish flammable liquid fires, supplementing water-based firefighting efforts with foam blankets that provide enhanced fire suppression and post-fire security.

What Types of Aqueous Film Forming Foam are There?

There are several types of Aqueous Film Forming Foam in use, with the most common two being synthetic-based and protein-based.

Synthetic-based Aqueous Film Forming Foam

Synthetic-based AFFF is the most commonly used type of AFFF and is formulated using synthetic fluorosurfactants and hydrocarbon surfactants. 

This type of AFFF offers excellent fire suppression performance and is compatible with a wide range of flammable liquids.

Protein-based Aqueous Film Forming Foam

Protein-based AFFF is less commonly used than synthetic-based AFFF and is formulated using natural protein-based surfactants derived from animal by-products. 

This type of AFFF has good burn-back resistance and is effective against certain types of flammable liquid fires. 

However, it may be less stable and more prone to degradation over time compared to synthetic-based AFFF.

Which to Choose?

Both types of AFFF are available in various concentrations, typically ranging from 1% to 6%, with higher concentrations providing increased firefighting effectiveness. 

The choice between synthetic-based and protein-based AFFF depends on factors such as firefighting requirements, environmental considerations, and regulatory compliance. 

While synthetic-based AFFF is more commonly used due to its superior performance and stability, protein-based AFFF may be preferred in certain applications or environments where synthetic-based AFFF is not suitable.

What are the Benefits of Aqueous Film Forming Foam?

Aqueous Film Forming Foam has a wide range of benefits. 

Some of the main ones are:

Rapid Fire Suppression

Aqueous Film Forming Foam offers rapid fire suppression capabilities, quickly smothering flames and preventing the spread of fire. 

The foam blanket formed by AFFF effectively seals off the fuel source, cutting off the oxygen supply and extinguishing the fire.

Burn-back Resistance

AFFF provides excellent burn-back resistance, meaning that once the fire is extinguished, the foam blanket remains in place to prevent re-ignition. 

This helps to ensure that the fire does not reignite after suppression efforts have ceased, providing enhanced post-fire security.

Versatility

Aqueous Film Forming Foam is versatile and adaptable, capable of extinguishing fires involving a wide range of flammable liquids, including oil, gasoline, diesel, and solvents. 

Its effectiveness across different types of fuel fires makes it a valuable tool in various industries and firefighting scenarios.

Stability

AFFF foam blankets are stable and long-lasting, maintaining their integrity even under adverse conditions such as high temperatures or turbulent environments. 

This stability ensures consistent firefighting performance and minimises the risk of foam degradation during storage or deployment.

Environmental Compatibility

Some formulations of Aqueous Film Forming Foam are designed to be environmentally friendly, with reduced toxicity and minimal impact on the environment. 

These eco-friendly AFFF formulations meet stringent environmental regulations and are suitable for use in environmentally sensitive areas.

Cost-effectiveness

AFFF is cost-effective compared to other firefighting agents, offering efficient fire suppression capabilities at a relatively low cost. 

Its affordability makes it accessible to a wide range of industries and organisations, from large-scale industrial facilities to small businesses and municipal fire departments.

What are the Downsides of Aqueous Film Forming Foam?

White Aqueous Film Forming Foam has numerous advantages to its use, it does come with various negatives that must be addressed. 

Some of the most common downsides are:

Environmental Impact

One of the main downsides of Aqueous Film Forming Foam is its environmental impact. AFFF contains fluorosurfactants, which can persist in the environment and pose potential risks to ecosystems and human health. 

These fluorosurfactants can bioaccumulate in aquatic organisms and have been linked to adverse effects on wildlife and aquatic habitats.

Health Concerns

In addition to environmental concerns, AFFF may also pose health risks to firefighters and other individuals exposed to the foam. 

Some formulations of AFFF contain per- and polyfluoroalkyl substances (PFAS), which have been associated with various health issues, including cancer, reproductive problems, and immune system disorders. 

Prolonged or repeated exposure to AFFF foam may increase the risk of adverse health effects.

Cleanup and Disposal Challenges

Aqueous Film Forming Foam can be challenging to clean up and dispose of properly after firefighting operations. 

The foam can accumulate in waterways, soil, and groundwater, leading to contamination and environmental damage. 

Proper cleanup and disposal procedures are necessary to minimise the environmental impact of AFFF and prevent long-term contamination of soil and water resources.

Regulatory Restrictions

Due to concerns about the environmental and health impacts of AFFF, regulatory agencies have implemented restrictions on its use and disposal. 

Some jurisdictions have banned or restricted the use of AFFF containing certain fluorosurfactants or PFAS compounds. 

These regulations may limit the availability and use of AFFF in certain regions or industries, requiring alternative firefighting agents to be used instead.

What are the Alternatives of Aqueous Film Forming Foam?

Due to some of the disadvantages of using Aqueous Film Forming Foam, alternatives can be used:

Dry Chemical Agents

Dry chemical agents, such as monoammonium phosphate (MAP) and sodium bicarbonate, are commonly used alternatives to Aqueous Film Forming Foam for extinguishing flammable liquid fires. 

These agents work by interrupting the chemical reaction of the fire and are particularly effective against Class B fires involving flammable liquids and gases. 

Dry chemical agents are available in portable extinguishers and fixed fire suppression systems, offering rapid and efficient fire suppression capabilities.

Carbon Dioxide (CO2)

Carbon dioxide (CO2) is another alternative firefighting agent used for extinguishing flammable liquid fires. 

CO2 works by displacing oxygen from the fire area, effectively smothering the flames and preventing combustion. 

CO2 is non-conductive and leaves no residue, making it suitable for use in electrical and sensitive equipment environments. 

However, CO2 can be dangerous in confined spaces due to the risk of oxygen depletion, and proper ventilation is necessary when using CO2 for fire suppression.

Environmentally Friendly Foam Formulations

In response to environmental concerns associated with traditional AFFF formulations, manufacturers have developed foam concentrates with environmentally friendly formulations. 

These foam concentrates are free from fluorosurfactants and per- and polyfluoroalkyl substances (PFAS), reducing their environmental impact and potential health risks. 

While these environmentally friendly foam concentrates may have slightly different firefighting properties compared to traditional AFFF, they offer effective fire suppression capabilities while minimising environmental harm.

Water-Based Firefighting Systems

Water-based firefighting systems, such as sprinkler systems and water mist systems, provide an alternative approach to fire suppression without the use of foam agents. 

These systems use water as the primary extinguishing agent, either through sprinkler heads or high-pressure water mist nozzles. 

Water-based firefighting systems are effective at suppressing fires involving flammable liquids and are often used in industrial and commercial settings for fire protection. 

Additionally, water-based systems are environmentally friendly and pose minimal health risks compared to foam agents.

Conclusion

Aqueous Film Forming Foam stands as a powerful tool in firefighting, offering rapid fire suppression capabilities for flammable liquid fires. 

While AFFF provides numerous benefits, including quick extinguishment and excellent burn-back resistance, it also presents downsides such as environmental impact and health concerns. 

Exploring alternatives like dry chemical agents, carbon dioxide, environmentally friendly foam concentrates, and water-based firefighting systems can mitigate these drawbacks. 

As the firefighting industry evolves, balancing the effectiveness of AFFF with environmental and health considerations remains crucial in ensuring comprehensive fire protection strategies for both present and future needs.