Foam Flashcards
The resulting finished foam extinguishes and/or prevents fire by the following methods:
_____-creates a barrier between the fuel and burning vapors
______-lowers the temperature of the fuel and adjacent surfaces
_______-prevents the release of additional flammable vapors, access to oxygen in the atmosphere, and therefore reduces the possibility of ignition or reignition
Separating
Cooling
Suppressing (sometimes referred to as smothering)
_____, ____, ____, and ____ are needed to produce a foam blanket.
Foam concentrate, water, air, and mechanical aeration
_____- liquid found in a foam storage container before the introduction of water.
Foam concentrate
________- mixture in the proper ratio of foam concentrate and water before the introduction of air.
Foam solution
____-device that mixes foam concentrate in the proper ratio with water.
Foam proportioner
____- completed product after air is introduced into the foam solution and after it leaves the nozzle or aerator.
Finished foam
Foam expansion is an increase in volume of ____ when it is aerated.
Foam solution
_____ is a key characteristic to consider when choosing a foam concentrate for a specific application.
Expansion
The method of aerating a foam solution results in varying _______,…
Varying degrees of expansion
Foam concentrates can be as one of three types:_____, ____, and _____
Low-expansion, medium-expansion, and high-expansion
NFPA ___ states that low-expansion foam has an air solution ratio _____ parts finished foam for every part of foam solution(____ ratio). Medium-expansion foam is most commonly used at the rate of _________through _________devices. In the high-expansion foam category, the rate is _____________.
NFPA 11 20 parts 20:1 ratio 20:1 to 200:1 through hydraulically operated nozzle style devices 200:1 to 1000:1
Most modern foam concentrates may be stored for long periods of time (in excess of ____). Optimum storage life can be achieved by ______________. UL-listed foam concentrates have storage temperature requirements of not less than _______ and not higher than ______.
IN EXCESS OF 10 years
Following manufacturers’ recommendations on foam concentrate storage containers and their related environmental conditions.
NOT LESS THAN 35 F (1.6C)
NOT HIGHER THAN 120 F (48.8C)
Freezing and thawing shall have ______ on UL-listed foam concentrate performance. UL-listed foam concentrates are shipped in “____” containers that must pass drop and impact tests with their contents ______.
No-effect
“Standard” containers
Contents frozen
Class A and Class B foam concentrates may be mildly _____.
Mildly corrosive
NFPA has established maximum allowable corrosion rates for Class A foam concentrates in NFPA _____.
NFPA 1150
Foam concentrates, either at full strength or in diluted form, pose ____ health risks to fire and emergency services responders. In both forms, concentrates may be ___ to the skin and eyes, so flush affected areas with water. Concentrates, or their vapors, may be ____ if ingested or inhaled.
Minimal health risks
Mildly irritating to skin and eyes
Harmful
_______, ___________, and _______ are all compatible with carbon dioxide, halon substitutes, and dry chemical agents and may be simultaneously discharged with them. Using foam, a halon-substitute, and dry chemical agents together is commonly referred to as a ______.
Aqueous film forming foam (AFFF), Film forming flouroprotein (FFFP), and flouroprotein foams
Multiagent attack
The biodegradability in either solution or concentrate form is determined by the rate at which _____________ dissolve or degrade the foam. This decomposition process results in the _____ of oxygen. The _______ that is required to degrade a particular foam, the better or more environmentally friendly the foam is when it enters a body of water. Studies by the US Forest service and the National Biological service office show that _____ foams can have a lethal affect on fish.
Environmental bacterias
Consumption of oxygen
The less oxygen
Class A foams
Where _________ is concerned, environmental issues revolve around ______ and _________. Some (____) use (____)as a water dispersing solvent and refractive index tracker, which is used to determine the concentration of finished foam when it has been applied to a fuel. The US Environmental Protection Agency determined that both ____ and _____ might be hazardous to the environment.
AFFF concentrate
Glycol ethers(also known as butylcarbitol) and perflouro-octylsulfonates(PFOS)
Some AFFF foam concentrates use butylcarbitol
Both glycol ethers and PFOS
Military specification AFFF foam concentrate formulations are not environmentally friendly solvents. In ______ , the US Navy began seeking alternative products to replace PFOS and glycol ether foam concentrates with those that are both compatible with _______ and the _________.
May, 2001
Saltwater and the environment
Class A foam concentrates require ___________ approvals from the ________ where environmental issues are concerns. NFPA ___ addresses environmental issues associated with Class A foam concentrates.
US forest service approvals
US department of agriculture
NFPA 1150
______ plays a role in finished foam effectiveness
Drainage (also referred to as quarter-drain time, 25-percent drainage time, or quarter life)
________ continue to wet the fuel as they drain
Class A foams
______ form a film over the surface of the fuel as they drain.
Aqueous film forming foams
A short drain time means _____. A long drain time means that the foam blanket ______ and provides an ____________ for an extended period before the water releases. Several elements affect the drainage process: _____, ____, ____, and to a lesser extent _____.
Rapid wetting
Insulating foam layer
Fuel temperature, heat of the fire, size of the flame front, and to a lesser extent, ambient air temperature and wind.
Some foam concentrates are thick and viscous. The concentrates are typically _____ foams and produce finished foam that can form tough, heat resistant blankets that drain slowly when proportioned at higher ratios of water and concentrate.
Typically alcohol-resistant aqueous film forming foams
Thinner concentrates are generally found in the ______ or ___ foams. ____ and _____ tend to be fast drainers that spread rapidly across liquid fuel surfaces, sending a quick spreading film ahead of the actual foam blanket. The draining ______ foam blanket becomes the reservoir for continued water-filming action.
Nonalcohol-resistant (regular AFFF, FFFP, and flouroprotein foam) or Class A foams
AFFF and FFFP
AFFF
Others, such as high-expansion foam concentrates, are used from __ to __ percent concentrations to produce large volumes of finished foam for flooding _______.
1 to 2.5 percent
Flooding confined spaces
It has long been known that ___ added to water will improve its absorption into class A materials.
Wetting agents (non-foaming, ionic, and non-ionic surfactants)
Wetting agents have been in use in the fire-suppression industry since the _____. However, Class A products have only been in use since the _______. During the _________, proportioning technology improvements increased the popularity and effectiveness of both Class A foams and wetting agents.
1940s
Late 1970s
1980s and 1990s
_________ concentrate is a formulation of hydrocarbon surfactants.
These ionic and non-ionic surfactants help reduce waters ____ in the foam solution. When used in conjunction with a _____, Class A foam has outstanding reach and insulating qualities. ______ typically entrain one or more parts of air with one part water.
Class A foam
Surface tension
Compressed-air foam system(CAFS)
CAFS
Class A foam may be used with ____nozzles, _____ nozzles, _____ devices, and ______ systems using almost any nozzle, including ____ nozzles.
Fog nozzles Aerating foam nozzles Medium and high-expansion devices compressed-air foam systems Solid stream nozzles
The shelf life of Class A foam concentrate is _____. Because this type of foam concentrate is used in very small percentages in the foam solution, __________ is not a concern under ordinary fire-suppression conditions.
Indefinite
Harm to the environment
Aeration of the water/concentrate foam solution into a volume of bubbles that is greater than the volume of the solution is referred to as ______ and is expressed in _____ such as 2:1, 5:1, 10:1 etc.
_____, _____, _____, and _____ all affect the obtainable (___).
Expansion ratio
Air/solution ratio
Water quality, aeration method, concentrate ratio, and concentrate formulation
Expansion ratio
The amount of liquid that drains from the bubble mass to wet and/or penetrate the Class A fuel is affected by the _____.
Class A foam with a low-expansion ratio drains _____ than does Class A foam with a high-expansion ratio. Generally, finished foam with a ________ ratio produces a quicker knockdown than does foam with a _____ ratio.
Expansion ratio
Faster
Low-expansion
High-expansion
_____ are best for the development of long-lasting finished Class A foam that can adhere to surfaces (horizontal, vertical, and overhead). They also provide an ______and minimize the ______ to Class A fuels. _____ tend to break down more rapidly and release more liquid to wet and penetrate the Class A fuel. ________ is an important consideration when establishing Class A foam delivery to a fire. Class A foam does not adhere to hot, vertical fuel surfaces that are in excess of _____.
Small bubbles of a consistent size Insulation barrier and minimize the oxygen supply Large bubbles Consistency 212F (100C)
_________ is an important consideration when establishing Class A foam delivery to a fire.
Consistency
The characteristic of Class A foam to remain on and in the fuel, reduce the fuel temperature, and increase the fuel moisture content is known as _________. _____, _____, _____, and ____ affect (____)
Retention
Air temperature, wind movement, the fuels latent heat, and the amount of heat present affect retention.
______ refers to a liquids thickness or ability to flow. Highly (___) liquid concentrates are very thick and may be difficult to _______ through some types of _______. ________ affects (____).
Viscosity
Highly-viscous
Proportion through some types of foam concentrate pumps
Temperature affects viscosity
Class A foam concentrates are mixed in proportions of ___ to __. Class A foam drain times ________ with an increase in the proportioning ratio. A rich concentrate/water mixture ratio produces thicker, richer foam that drains _____ than a lean ratio. Most FOAM nozzles produce more stable finished foams at a ___ concentration than they do at ___ to ___ concentrations. Employing percentages greater than ___ percent with STANDARD fog nozzles does not appear to increase firefighting performance. Exposure protection may be enhanced with applying Class A foam through FOG nozzles at _______ proportioning settings.
0.1 to 1 percent Increase Slower 1 percent 0.4 to 0.5 GREATER THAN 0.5 1 percent OR GREATER
______ refers to the amount of finished foam that must be applied to a fire, per hour, per square foot of fire. In structural firefighting combat, the (____) is the same as the ______ for water. Knowing the correct (________) is important during emergency operations. Do not reduce _______ rates when using Class A foam.
Application rate
Application rate is the same as the minimum flow rate for water
Application rates
Do not reduce initial attack flow rates
____, ____, ____, and ____ strongly influence the course of a wildland fire. A common problem with fires involving heavy brush is the difficulty fire and emergency responders have in applying water to the ____________. The addition of Class A foam concentrates into a wildland fire attack aids the _____ of water to the concealed areas of the fuel. The _____ characteristics of class A foam also allow water to seep more quickly into vegetation with a low moisture content.
Fuel density, fuel composition, climatic conditions, and fuel and moisture content
Underside of vegetation
Absorption
Soaking
_____ create special tactical problems for fire and emergency responders. The incident priority of ____ is of greatest importance.
Civil disturbances
Life safety
_________ foam is beneficial for rapid fire extinguishment when water supplies are limited or become disrupted during the operation.
Class A finished foam
_____ and ______ provide the advantage that is lost by limited personnel during an initial response. The _____ foam extinguishing agent reduces the fire more rapidly, cools the interior of the structure, and prevents reignition within the structure. ________ has the advantage of providing quick fire extinguishment from great distances, while allowing for the maneuverability of the hoseline by fewer people.
Class A finished foam and compressed-air foam systems
Class A
A CAFS
_____ extinguishes fires involving flammable and combustible liquids. It also ____ from unignited spills of these liquids.
Class B foam
Suppresses vapors
Class B FINISHED foam may be proportioned into the fire stream via a ______, _______, or ______.
Fixed system, an apparatus-mounted system, or portable foam proportioning equipment
The [Class B] foam may be applied either with _______nozzles or with _______ nozzles.
Standard fog nozzles (AFFF and FFFP concentrates) or with air aspirating foam nozzles (all types)
Class B foam concentrates are manufactured from either a ____ or ____ base. (____) concentrates are derived from animal protein. (___) concentrate is made from a mixture of flourosurfactants. Some foam concentrates are made from a combination of ____ and ____ bases.
Synthetic or protein base
Protein-based foam concentrates
Synthetic foam concentrate
Combination of synthetic and protein bases
