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Colleton County Fire-RescueTraining Division
Foam Firefighting
Section IV
Foam Application and Operations
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
Objectives
• Discuss considerations for after foam is applied
• Discuss the strategies for exposure protection for Class B fire incidents.
• Discuss water supply considerations.
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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
Colleton County Fire-RescueTraining Division
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!!!
Colleton County Fire-RescueTraining Division
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
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
Class A Foam and Structural Fire Attack
• 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.
Colleton County Fire-RescueTraining Division
Class A Foam and Structural Fire Attack
• Fog nozzles should be used on low energy foam lines.
• Fog or smoothbore nozzles may be used with CAFS systems.
Colleton County Fire-RescueTraining Division
Class A Foam and Structural Fire Attack
• 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.
Colleton County Fire-RescueTraining Division
Class A Foam and exposure Protection
• Excellent for protecting exposures.
• Insulating properties protect unburned areas.
• Type 2 or Type 3 foam is recommended
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
Class A Foam Overhaul Operations
• Drastically reduces the amount of water used.– Limited runoff– Less water damage
Colleton County Fire-RescueTraining Division
Class A Foam Overhaul Operations
• Thermal blocking occurs when concealed hot spots contain enough heat to turn small amounts of penetrating water into steam.
Colleton County Fire-RescueTraining Division
Class A Foam Overhaul Operations
• The use of foam helps defeat the phenomenon of thermal blocking by enabling more water to penetrate deeper and speed the cooling process.
Colleton County Fire-RescueTraining Division
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
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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
Colleton County Fire-RescueTraining Division
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
Colleton County Fire-RescueTraining Division
Type of Fuel
• Hydrocarbon
• Polar Solvent
• Toxic or Non Toxic
• Water Reactive
Colleton County Fire-RescueTraining Division
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
Colleton County Fire-RescueTraining Division
Amount of Foam Concentrate
Application Rate (In GPM)
X
Discharge time (15 min)
X
Proportioning Rate (.03 or .06)
=
Concentrate Required
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
Techniques of Class B Foam Application.
• Air Aspirated Foam
• Non Air Aspirated
Colleton County Fire-RescueTraining Division
Air Aspirated Foam
Advantages
• Foam is longer lasting.
• Longer drainage time.
• Highest quality.
Colleton County Fire-RescueTraining Division
Air Aspirated Foam
Disadvantages
• Short Reach
• Affected by wind conditions
• Nozzles can be bulky and may be single purpose.
Colleton County Fire-RescueTraining Division
Non Air Aspirated Foam
Advantages
• Can be applied through any standard fog nozzle.
• Greater reach and penetrating power
• Faster knockdown in lab tests.
Colleton County Fire-RescueTraining Division
Non Air Aspirated Foam
Disadvantages
• Will not form as thick of a blanket.
• Requires more frequent re-application.
Colleton County Fire-RescueTraining Division
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).
Colleton County Fire-RescueTraining Division
Exposure Protection
• Not different from structural fire exposure protection.
• Judgmental decision based on the situation.
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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?
Colleton County Fire-RescueTraining Division
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 .
Colleton County Fire-RescueTraining Division
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.
Colleton County Fire-RescueTraining Division
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