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Colleton County Fire-RescueTraining Division

Foam Firefighting

Section IV

Foam Application and Operations


Objectives

• Discuss the principals and considerations for fighting Class A fires.

• Dispel myths surrounding Class A foam

• Discuss Class A Foam for structural fire attack.

• Discuss the effectiveness of Class A foam for exposure protection.


Objectives

• Discuss Class A foam’s benefits during overhaul.

• Define the principals of Class B fire attack.

• Discuss the techniques of Class B foam application.


Objectives

• Discuss considerations for after foam is applied

• Discuss the strategies for exposure protection for Class B fire incidents.

• Discuss water supply considerations.


Principals and Considerations for Fighting Class A Fires

• Class A foam is biodegradable when used in small ratios of .01-1.0%.

• Considerations should still be made to keep runoff out of sewers lakes and streams.

• Use proper PPE when handling concentrates.


Principals and Considerations for Fighting Class A Fires

• Clean PPE thoroughly if it has been soaked in concentrates.

• Have backup lines in operation when high energy foam systems are in use.

• Foam proportioning ratios can be tailored to suit the job.


Class A Foam Common Myth

Some people have promoted the theory that 200 of a foam solution aspirated to a 10:1 expansion ration actually gives you the fire

protection capability of 2,000 gallons of water.

False


Class A Foam Myth Dispelled

• Class A foam only makes water more efficient at soaking into the fuel and absorbing heat.

• Less water is required to extinguish a fire than if plain water is used.

• It does not create more water!!!


Class A Foam Common Myth

Foam lines may be flowed at lower application rates or from smaller hose

lines than those of plain water.

False


Class A Foam Myth Dispelled

• There is no reputable scientific data to prove this point.

• Shorter discharge times results in less water being used.

• It is recommended that foam solution flow rates and hose sizes be the same as the generally accepted flow rates and hose sizes for plain water.


Class A Foam and Structural Fire Attack

• Most effective on interior fire attacks.

• Must be applied directly to the burning material to be most effective.

• Helps maintain visibility due to less steam conversion.



• When using Class A foam for an interior attack use with either a direct or combination attack.

• Reduces time a fire stream needs to be applied.



• Fog nozzles should be used on low energy foam lines.

• Fog or smoothbore nozzles may be used with CAFS systems.



• CAFS fire streams are well suited for exterior fire attacks.

• The extended reach assures that the foam is being delivered deep into the structure.

• The fire can be knocked down quickly from a window or a doorway.


Class A Foam and exposure Protection

• Excellent for protecting exposures.

• Insulating properties protect unburned areas.

• Type 2 or Type 3 foam is recommended


Class A Foam Overhaul Operations

• Class A foam exhibits some of it’s greatest benefits during overhaul operations.

• Applied in the same fashion as water with standard nozzles and techniques.



• Drastically reduces the amount of water used.– Limited runoff– Less water damage



• Thermal blocking occurs when concealed hot spots contain enough heat to turn small amounts of penetrating water into steam.



• The use of foam helps defeat the phenomenon of thermal blocking by enabling more water to penetrate deeper and speed the cooling process.


Principals of Class B Fire Attack.

• Size of the fire

• Type of fuel

• Required application rate

• Amount of foam concentrate needed and available

• Ability to deliver and sustain the required foam rate


Size of the Fire

• Almost always involve the entire surface of an exposed fuel.

• May remain that size throughout the duration of the incident.

• Coincidently the size of the fire is fairly constant throughout the incident.


Size of the Fire

Determining the size of the fire in a circular enclosure in square feet.

Area = 3.14 X Radius²

Determining the size of the fire in a square or rectangular enclosure in square feet.

Area = Length X Width


Size of the Fire

If the Fire Involves a Spill Area

• Determine the maximum length and width of the spill and multiply by those numbers


Type of Fuel

• Hydrocarbon

• Polar Solvent

• Toxic or Non Toxic

• Water Reactive


Application Rate

Sq ft (X) 0.1 for Hydrocarbons = Application Rate in GPM

Sq ft (X) 0.2 for Polar Solvents = Application Rate in GPM


Amount of Foam Concentrate

Application Rate (In GPM)

X

Discharge time (15 min)

X

Proportioning Rate (.03 or .06)

=

Concentrate Required


Ability to Deliver and Sustain the Required Foam Rate

• Have enough foam on hand

• Have enough water – GPM (X) 15 min (–) Concentrate Required = Water Required

• Have the proper equipment to flow the required application rate.


Techniques of Class B Foam Application.

• Air Aspirated Foam

• Non Air Aspirated


Air Aspirated Foam

Advantages

• Foam is longer lasting.

• Longer drainage time.

• Highest quality.


Air Aspirated Foam

Disadvantages

• Short Reach

• Affected by wind conditions

• Nozzles can be bulky and may be single purpose.


Non Air Aspirated Foam

Advantages

• Can be applied through any standard fog nozzle.

• Greater reach and penetrating power

• Faster knockdown in lab tests.


Non Air Aspirated Foam

Disadvantages

• Will not form as thick of a blanket.

• Requires more frequent re-application.


Manual Application Techniques

• Roll On Method (roll foam onto leading edge of spill or fire and roll foam toward the back).

• Bank Down Method (hit an elevated object above the spill or fire).

• Rain Down Method (foam is sprayed above and is rained down on spill or fire).


Exposure Protection

• Not different from structural fire exposure protection.

• Judgmental decision based on the situation.


After Foam is Applied

• Protect your foam blanket at all costs.

• Insure that no smoking or other sources of ignition around the blanket.

• Insure that blanket is not broken, walked or driven through.

• Insure that your hoses are not part of the spill.


Situations to Consider Exposure Protection

• A large fire that cannot be immediately extinguished.

• Employing a nonintervention strategy.

• Extremely sensitive structures. (fuel tanks, etc)

• Structures in the vicinity showing the effects of exposure to the fire.


Factors That Determine the Danger of an Exposure

• Amount and intensity of the original fire.

• Proximity of the exposure to the fire.

• Wind and weather conditions.

• Composition of the exterior of the exposure.


Water Supply Considerations

• Foam operations usually require significant amounts of water.

• Have the required water available before beginning foam operations.

• Rule of thumb is 1 gallon per min for every 10 sq ft.


Water Supply Considerations

Questions to ask

• What is my water requirements?

• What is my water supply available?

• Does access to the scene inhibit my ability to deliver the required flow?


Summary

• Principals and considerations for fighting Class A and Class B fires vary.

• There are may myths myths surrounding Class A foam

• Class A Foam is an effective tactic for structural fire attack, exposure protection and overhaul.

• Techniques of Class B foam application vary with the prescribed application and take in account many considerations .


Summary

• What are the considerations after Class B foam is applied?

• Exposure protection for Class B fire incidents are integral to an effective incident management strategy.

• Water supply considerations for Class B Foam operations.


Questions???


Acknowledgements

• IFSTA Principals of Foam Firefighting 1st Edition, 1996

• Dominic Colletti, Class A Foam-Best Practice for Structural Firefighters, 1998

• Various Web Sources

• Task Force Tips

• Elkhart Brass Manufacturing

• Operations Chief David A Greene