All About Alcohol Resistant Foam

In the early 1970s, National Foam, Inc. invented alcohol-resistant AFFF technology. Alcohol resistant foam extinguishers are specifically designed to combat fires involving flammable liquids, including alcohol-based substances, which can break down regular foams. Here’s how they work:

Special Foam Composition:

Alcohol-resistant foam extinguishers contain a thickening agent that prevents the foam from breaking down when it comes into contact with alcohol or other polar solvents (like acetone or esters). Regular foams would dissolve when they hit such substances, but alcohol-resistant foams create a barrier that holds up and suffocates the fire from the oxygen source. The alcohol-resistant foam creates a thicker and more stable layer that effectively suppresses flames from alcohol or solvent-based fires, unlike standard foams that would dissolve quickly in such environments.

 

Forming a Sealing Layer:

When the extinguisher is discharged, it forms a blanket of foam that covers the surface of the burning liquid. Alcohol-resistant foam must be bounced off of a surface and allowed to flow down

and over the liquid to form its membrane. The foam is designed to:

• Smother the fire: By covering the liquid surface, the foam cuts off the oxygen supply, which helps extinguish the fire.
• Suppress vapor release: The foam layer traps flammable vapours, preventing them from reigniting or spreading the fire.
• Resist breakdown: The foam is designed to resist mixing with the alcohol or solvent, maintaining its protective barrier for longer

How it’s Used:

Here’s how to use a Foam Extinguisher

1. Assess the Fire

• Ensure the fire is manageable and you feel safe tackling it.
• Use the alcohol-resistant foam extinguisher on Class B fires, which involve flammable liquids such as alcohol, fuel, or solvents. It can also be used on Class A fires, which involve solid materials like wood, paper, and textiles.

2. Pull the Pin

• Remove the safety pin to unlock the extinguisher’s handle. This breaks the seal and allows you to discharge the extinguisher.

3. Aim at the Base of the Fire

• Stand a safe distance away (about 6-10 feet) and aim the nozzle at the base of the fire, not the flames themselves. For alcohol fires, the foam works by creating a blanket that suppresses the fire and prevents re-ignition.

4. Squeeze the Handle

• Squeeze the handle to release the foam. Control the flow, applying the foam in a sweeping motion.

5. Sweep from Side to Side

• Move the nozzle from side to side, ensuring the foam fully covers the burning material. Focus on covering the entire surface to create a protective barrier that separates the fuel from oxygen.

6. Monitor the Fire

• Continue applying the foam until the fire is completely out. Even after the flames disappear, keep applying foam for a few more seconds to prevent re-ignition.

7. Evacuate and Call for Help

• If the fire doesn’t seem to be controlled, evacuate immediately and call emergency services. Don’t take unnecessary risks.

 

Where An Alcohol Resistant Foam Extinguisher Should be Used

• Bars and Restaurants
• Brewers and Distilleries
• Fuel Stations and Refineries
• Laboratories
• Airports
• Manufacturing and Industrial Sites
• Warehouses storing alcohol, cleaning solvents, chemical products etc
• Paint Stores that sell alcohol based products such as thinners
• Shipping and Transport Terminals