Structural Fire Fighting: Initial Response Strategy And Tactids 3rd Edition Flashcards
_____ is the study of matter and energy and includes chemistry and physics.
Physical science
A _____ change occurs when a substance remains chemically the same but changes in size, shape, or appearance. Example: water freezing or boiling.
Physical change
A _____ reaction occurs when a substance changes into another substance.
Chemical reaction
Oxidation is a _____ reaction.
Chemical
_____ energy is the energy a moving object possesses.
Kinetic energy
The quantity of heat required to change the temperature of 1 gram of water by 1 degree Celsius is _____ joules.
4.2
A Btu is the amount of heat required to raise the temperature of 1 pound of water by _____ degrees Fahrenheit.
1
_____ Joules = 1 Btu
1055 Joules
Reactions that emit energy as they occur are _____ reactions.
Exothermic
Fire is a/an _____ reaction.
Exothermic chemical reaction
Reactions that absorbs energy are _____ reactions.
Endothermic Reactions
Converting water from liquid to gas requires energy input resulting in a/an _____ reaction.
Endothermic Physical reaction
Fuels must be in a _____ state to burn.
Gaseous
In solids, off-gassing works as a chemical change known as _____.
Pyrolysis
In flammable liquids, a physical change is called _____.
Vaporization
_____ ignition is the most common form of ignition.
Piloted ignition
_____ occurs without any external flame or spark to ignite fuel gases or vapors.
Auto ignition
Fire triangle:
Fuel, oxygen and heat
_____ is the minimum temperature at which a fuel in the air must heat to start self-sustained combustion.
Autoignition temperature
Autoignition is always higher/lower than its piloted ignition.
Higher
_____ combustion produces smoke.
Incomplete combustion
_____ is a toxic flammable substance produced in the combustion of materials containing nitrogen.
Hydrogen Cyanide (HCN)
Class ___: Ordinary, solid, combustible materials such as wood, cloth, paper, rubber and many plastics.
Class A
Class ___: Flammable and combustible liquids and gases such as gasoline, oil, lacquer, paint, mineral spirits, and alcohol.
Class B
Class ___: Energized electrical equipment where the electrical nonconductivity of the extinguishing agent is of major importance. Materials involve are either Class A or Class B, and they can be extinguished once the equipment is deenergized.
Class C
Class ___: Combustible metals such as aluminum, magnesium, potassium, sodium, titanium, and zirconium.
Class D
Class ___: Oils and greases normally found in commercial kitchens and food preparation facilities using deep fryers.
Class K
____, _____, and _____ energy are most frequently the ignition sources of structure fires.
Chemical, electrical and mechanical energy
4 ways electrical heating can occur:
Resistance heating; overcurrent or overload; arcing; sparking
_____, or _____ generates mechanical energy.
Friction or compression
_____ energy is the most common source of heat in combustion reactions.
Chemical energy
_____ is heat transfer through and between solid objects. It occurs when a material heats as a result of direct contact with a heat source.
Conduction
_____ is the transfer of thermal energy by the circulation or movement of a fluid (gas or liquid). Usually involves heat transfer through the movement of hot smoke and fire gases.
Convection
_____ is the transmission of energy as electromagnetic waves. Can become the dominant heat transfer mode as a fire grows and can affect the ignition of objects some distance away from the fire.
Radiation
_____ typically causes exposure fires.
Radiation
A materials _____ determines the amount of heat it releases.
Chemical makeup
The standard international unit for power is the _____.
Watt (W)
1 Watt is ____ Joule/s per second (J/s).
1
_____ fuels can be the most dangerous of all types of fuels because they are already in the physical state required for ignition.
Gaseous
_____ describes the density of gases in relation to air.
Vapor Density
Air has a vapor density of ___.
1
Gases with a vapor density less than 1 will _____.
Rise
Methane is heavier or lighter than air?
Lighter
Gases with a vapor density of greater than 1 will _____.
Sink
_____ have mass and volume but no definite shape.
Liquids
_____ is the ratio of the mass of a given volume of a liquid compared with the mass of an equal volume of water at the same temperature.
Specific Gravity
Water holds a specific gravity of ___.
1
Liquids that hold a specific gravity of less than 1 will _____.
Float
Gasoline and most other flammable liquids have a specific gravity of greater/less than 1?
Less
Liquids with a specific gravity greater than 1 will _____.
Sink
Salt water has a specific gravity of greater/less than 1?
Greater
_____ indicates the minimum temperature at which a liquid gives off sufficient vapors to ignite, but not sustain combustion, in the presence of an ignition source.
Flash Point
_____ marks the temperature at which a piloted ignition of sufficient vapors will begin a sustained combustion reaction.
Fire point
The primary consideration in the ignition of solid fuels involves the surface area of the fuel in proportion to its mass, which is called the _____.
Surface to mass ratio
As a surface to mass ratio increases, the particles’ ability to ignite increases/decreases?
Increases
Normally air consists of about ___% oxygen.
21%
The range of a fuel vapor and air is called the _____.
Flammable range
The _____ stage starts with ignition when the three elements of the fire triangle come together and the combustion process begins. A this point, the fire is small and confined to a small portion of the fuel first ignited.
Incipient Stage
As the fire transitions to the _____ stage, more of the initial fuel package becomes involved and the production of heat and smoke increases. If there are other fuels close to the initial fuel package, the fire’s radiant heat may begin to pyrolyze nearby fuels, which could spread the fire to new fuel packages.
Growth Stage
The _____ stage occurs when all combustible materials in the compartment are burning at their peak HRR based on the available oxygen. This is when the fire consumes its maximum amount of oxygen.
Fully Developed Stage
As the fire consumes the available fuel or oxygen and the HRR declines, the fire enters the _____ stage.
Decay Stage
There are three factors that control how the fire develops:
The fuel properties
The ventilation available
Heat Conservation
A visual indicator that a fire is leaving the incipient stage is _____.
Flame height.
When flames reach _____ high, radiated heat begins to transfer more heat than convection. The fire will enter growth stage.
2.5 feet
Fire in fuel packages in the middle of the room can entrain air from _____ sides.
All sides
Fires in fuel packages near walls can entrain air from _____ sides.
3 sides
Fires in fuel packages in corners can entrain air from _____ sides.
2 sides
_____ is the tendency of gases to form into layers according to temperature, gas density, and pressure.
Thermal Layering
The appearance of isolated flames is sometimes an immediate indicator of _____.
Flashover
Higher pressure always flows to _____.
Lower pressure
_____ are rapid fire development incidents, but they involve more than one compartment of the structure.
Smoke Explosion
Rapid transition from the growth stage to the fully developed stage is _____.
Flashover
A significant indicator of flashover is _____.
Rollover
4 Common elements of flashover include:
Transition in fire development
Rapidity
Compartment
Pyrolysis of all exposed fuel surfaces
The Autoignition temperature of CO is approximately _____ degrees F.
1000 degrees F (595C)
4 Types of Flashover Indicators:
Building Indicators
Smoke Indicators
Heat Indicators
Flame Indicators
A ventilation limited compartment fire can produce a large volume of flammable smoke and other gases due to incomplete combustion:
Backdraft
To some degree, the violence of a backdraft depends upon the extent to which the fuel/air mixture is confined. The _____ confined, the _____ the backdraft.
More confined, the more violent
A _____ occurs when a mixture of unburned fuel gases and oxygen encounters an ignition source.
Smoke Explosion
The flow path is composed of two regions:
The ambient air flow in
The hot exhaust flow out
Wind can increase/decrease pressure inside the structure?
Increase
Most building codes rate the construction types according to _____.
How long each type maintains its structural integrity over time.
Information gathered _____ provides the best indicators of structural integrity.
At the scene
What is the most available fuel source?
A structures contents
_____ is the layout of the open spaces in a structure.
Building compartmentation
A fire in a large compartment will normally develop quicker/slower than a small compartment?
Slower
_____ and _____ in buildings contribute to the spread of fire.
Large, open spaces