Essnetials Of Firefighting 7th Ed Flashcards
All fires involve a heat producing chemical reaction between
Fuel and an Oxidizer
Oxygen in the Air.
Not combustible but will support or enhance combustion.
Oxidizers
Common Oxidizers
Calcium Hypochlorite (Granular Chlorine) Chlorine gas Ammonium Nitrate Hydrogen Peroxide Methyl Ethyl Ketone Peroxide.
Physical Science is the study of
Matter and Energy and includes chemistry and physics.
Occurs when a substance changes from one type of matter into another, such as two or more substances combing to form compounds.
Chemical Reaction.
Forms of energy are either ?
Potential or Kinetic
The energy available for releases in the combustion process is known as the ?
Heat of combustion.
The energy that a moving object processes ?
Kinetic Energy
Stored energy possessed by an object that can be released in the future to perform work once released.
Potential Energy
All Energy can change from
One type to another.
Energy is measured in
Joules (J) in the International System of Units (SI)
Customary = Btu
Heat required to change the temperature of 1 gram of water by 1 degree Celsius takes ?
4.2 joules
Anything that occupies space and has mass?
Matter
Smoke is an aerosol comprised of
Gas, vapor, and solid particulates.
Smoke is
Incomplete combustion.
Left over Fuel from incomplete combustion
Smoke and Ash
Carbon Based Fuels
Wood and Cotton
Plastic, synthetic fabrics, and other types
Hydrocarbon Fuels.
Petroleum based organic compound that contains only hydrogen and carbon.
The incomplete combustion of organic(carbon containing materials)
Carbon Monoxide (CO)
CO combines with hemoglobins about?
200 x more effectively than oxygen.
When two or more substances combine they form a
Compound.
Produced in the combustion of materials containing nitrogen.
(HCN)=Hydrogen Cyanide.
(HCN) Hydrogen Cyanide is 35 x more toxic than
(CO)Carbon Monoxide.
Force per unit of an area applied perpendicular to a surface
Pressure
The capacity to perform work
Energy
Moves from areas of higher pressures to areas of Lower pressure.
Gas
The most common source of heat in combustion reactions.
Chemical energy
Seven types of energy
Chemical Thermal Electrical Mechanical Light Nuclear Sound
Friction and Compression generate
mechanical energy
When a Gas is compressed
Heat is generated.
Objects at the same temperature do not
Transfer Heat
Three mechanism of heat transfer
Conduction
Convection
Radiation.
The amount of heat required to raise the temperature of 1 pound of water 1 degree Fahrenheit
Btu
Copper will conduct heat more than ——— faster than steel.
Seven Times
Forty times as thermally conductive as concrete.
Steel.
What type of change occurs when a substance changes in size, shape, or appearance, but chemically stays the same?
Physical Change: Water freezing, water boiling.
Insulator least able to conduct heat.
Air
Transfer of thermal energy by the circulation or movement of a fluid, liquid, or gas?
Convection.
Transmission of energy as electromagnet waves, light, radio, or x rays.
Radiation.
How many joules = 1 Btu?
1055 j
Reactions that absorb energy as they occur are
Endothermic reactions ex: converting water to steam
Reactions that emit energy as they occur are
Exothermic
Most common fuels are ?
Organic
The prefix Kilo indicates a multiple of
1000
Mega indicates a multiple of
1,000,000
Ex: kilowatt is 1000 watts and a megawatt is a 1,000,000 watts.
A chemical process of oxidation that occurs at a rate fast enough to produce heat and usually in the form of either a glow or a flame.
Combustion.
A rapid oxidation process, which is a chemical reaction resulting in the evolution of light and heat in varying intensities?
Fire
A form of energy characterized by vibration of molecules and capable of initiating and supporting chemical changes and change of state.
Heat
Minimum temperature at which a liquid gives off sufficient vapors to ignite.
Flash point
Temperature at which a piloted ignition of sufficient vapors will begin a sustain combustion reaction.
Fire point
Term commonly used to indicate the flammability hazard of liquid fuels.
Flash point
Measure of materials ability to transfer heat energy to other objects?
Temperature
What type of change occurs when a substance changes from one type of matter to another?
Chemical change
A material that will maintain combustion under specific environmental conditions.
Fuel
Any material that readily yields oxygen or other oxidizing gas, or that readily reacts to promote or initiate combustion of combustion materials.
Oxidizer.
Name two forms of ignition.
Piloted and Auto(non-piloted) ignition
Describes the extent to which a substance will mix with water.
Solubility
Solid, liquid, gas dissolves in a solvent usually water.
material that mixes in water in all proportions is called
Miscible
The most common type of ignition. Occurs when a mixture of fuel and oxygen encounters an external heat source with sufficient heat or thermal energy to start the combustion process.
Piloted Ignition.
The auto-ignition temperature of a substance is always higher then its
Piloted ignition temp.
Foams specifically designed for polar solvents?
Alcohol Resistant.
Minimum concentration of fuel vapor and air that supports combustion
(LEL)lower explosive limit
Concentration above to support combustion IE to rich to burn
(UEL)Upper explosive limit
The fuel in a combustion reaction is known as the ?
Reducing agent.
The range of concentrations of the fuel vapor and air is called ?
Flammable(explosive ) range.
A visual indicator that a fire is leaving the incipient stage is?
Flame height. When flames reach 2.5 feet.
Physical process that changes a liquid into a gaseous state; the rate depends on the substance involved, heat, pressure, and exposed surface area.
Vaporization
Name two modes of combustion
Flaming and non-flaming
A significant indicator of Flashover
Rollover
When a mixture of unburned fuel gases and oxygen comes in contact with an ignition source.
Smoke explosion
Occurs slowly, lower temps, produce a smoldering glow.
Nonflamming combustion
As Flashover occurs the Gas temperatures in the room reach
1100 degrees F (593C) or higher
The auto ignition temperature of CO
Approx 1100F
UL recommends when dealing with fires in solar panels crews should?
Apply water from a min of 15ft when using automatic nozzles.
20ft away when using smooth bore nozzles.
Natural gas in its pure form is
Methane
Flammability range of natural gas is
5% to 15% lighter than air.
Name the two models that are used to describe the element of fire and how to extinguish it
Fire Triangle and Fire Tetrahedron.
Materials that absorb heat but do not participate actively in the combustion process. Give a example.
Passive Agents.
Ex: Gypsum/Humidity
Situational awareness techniques for wildfires
“LCES”
Lookout, communication, escape routes, Safety zones.
Us department of Agriculture’s forest service in 1957 established
Ten standard Firefighting orders.
Fire Fighting Foam extinguishes and/or prevents ignition in several ways.
Separating, cooling, smothering, penetrating.
Petroleum-based combustible or Flammable liquids that Float on water such as gasoline.
Hydrocarbon Fuels.
Flammable liquids that mix readily with water such as ethanol
Polar Solvents
AFFF
Aqueous film forming foam
Class B foams
FFFP
Film forming Fluoroprotein Faom
Class B foams
A type of ventilation tactic to create a defensible line ahead of the fire spread when ventilating.
Trench Cut or strip ventilation.
Phenomenon of a strong air draft moving from ground level to the roof level of a building
Stack Effect
A Single cut the width of the saw blade made in a roof to check for fire extension.
Kerf cut