Not all foam pumpers operate behind the fences of industrial plants. Many municipal departments now operate pumpers equipped with Class B foam systems to handle a variety of incidents, ranging from minor highway accidents to major hazmat spills.

Some municipal foam pumpers are designed to protect industrial areas, harbors or airport facilities. These units need to handle big fires and usually have big pumps, large foam tanks and high-volume foam-proportioning systems. Other foam pumpers are designed to protect commercial districts, residential areas or transportation corridors. These units need to handle smaller fires and usually have more standard pumps, tanks and foam systems.

Big or small, all foam pumpers have the advantage of being able to handle a much wider range of fires than those that rely on water alone. Here are some situations where a pumper equipped with Class B foam might be the difference between a raging fire and a pile of soap suds.

Highway accidents

The steady increase in highway traffic in urban and suburban areas usually results in a corresponding increase in motor-vehicle accidents. The responding fire department not only has to extricate the victims, but also provide fire protection and suppression until the vehicles are cleared and the scene is secured. Although some departments may have used water sprays to handle small vehicle fires in the past, the use of ethanol-based fuels may require alcohol-resistant foams to provide appropriate fire suppression in the future.

Railroad derailments

Any train that rolls through a town potentially carries a wide variety of flammable materials. A piece of debris on the tracks, a loose tieplate or an impatient motorist is all that's needed to cause a derailment. While some accidents result in large and immediate fires that are best handled by a general evacuation of the area, others result in small leaks or spills that often can be neutralized by applying a blanket of foam.

Ship and barge fires

Departments that protect areas adjacent to navigable rivers and other waterways face the possibility of having to deal with flammable liquid fires aboard ships and barges. This is especially true in areas where ships are loaded or unloaded. Again, having the right foam can make the difference.

Airport fuel fires

Almost all airports have fuel storage facilities, pipelines and fuel trucks to shuttle the fuel to aircraft on the field. Regulations governing the number and size of airport rescue and firefighting apparatus are based on the frequency of passenger flights and the overall length of the passenger aircraft. In some cases, all that's required is a small twin-agent unit. Departments that are responsible for providing general fire protection at an airport should consider the fuel storage areas as well.

Petrochemical industry fires

Some industries aren't as big as oil refineries, but they pose similar hazards. Many manufacturing plants use what are known as petrochemical feedstocks to produce a wide range of end products. To ensure a steady supply, some plants store the raw materials on site. Departments should be aware of the hazards involved with specific industries in their areas and the extinguishing agents required to handle fires. Foam may be part of the solution.

Hazmat support

Some departments dispatch foam pumpers to all incidents involving hazardous materials. The theory is simple: A leaking 55-gallon drum in a ditch may contain vegetable oil or it may contain paint thinner. To err on the side of safety, departments often choose to provide adequate fire protection until the materials are identified, contained and safely removed.

New fires need new foams

Making the decision to specify a foam pumper is only the first step. Departments also need to consider the type of Class B fires they may be facing and the type of foam required. In turn, that will help decide the type of foam proportioning system, the size of the foam tank, the storage and handling procedures for the foam, and several other factors.

Class B foams come in many types, including detergent, protein, fluoroprotein, aqueous film-forming foam and others. AFFF is the most common, and it can be used for fires involving gasoline, kerosene, diesel fuel and other hydrocarbons. It does not work for fires involving alcohol and other polar solvents that mix with water. Those fires require an alcohol-resistant foam. Departments in areas where alcohol products are stored or where the new gasoline with up to 85% ethyl alcohol is being sold will need to use AFFF — AR or another alcohol-resistant foam.

The best way to deal with all these considerations is to ask a foam expert. Many foam manufacturers publish guidebooks and have knowledgeable people to answer specific questions.

The next time you evaluate the hazards in your area, consider all the situations where you could use Class B foam. Maybe it's time to make your next pumper a foam pumper.