EXAM Questions Flashcards
Ch. 2
The national Fire Academy developed a formula for estimating fire flow based on the percent of involvement of the structure or compartment. The formula was intended for both preincident planning and for on-scene calculations at the incident. What is that formula?
A. Needed fire flow (PSI) = (LxW)/3 x % involved
B. Needed fire flow (GPM) = (LxW)/3 x % involved
C. Needed fire flow (GPM) = (Static-Residual)(100) / static
D. Needed fire flow (PSI) = (Static- Residual)(100) / Static
B. needed fire flow (GPM) = (LxW) / 3 x % involvement.
Percent involvement generally calculated for 25% increments involvement.
It is intended for interior fire attack in a compartment or structure that is not more than 50% involved.
Ch. 4 The movement of smoke can be described in terms of \_\_\_\_\_\_ and \_\_\_\_\_. A. density, volume B. volume, pressure C. Speed, pressure D. speed, direction
D. Speed, direction
Ch. 1 Fire Dynamics The most common types of energy that result in the ignition of a fuel. Which of the following is not one of the three. A. Chemical B. Thermal C. Mechanical D. Electrical
B. Thermal energy.
Chemical, electrical and Mechanical energy all transfer heat, cause the temperature of a substance in increase, and are most frequently the ignition sources of structure fires.
Ch.1 fire dynamics: conduction
The best commercial insulators used in building construction are those made of:
A. Fiberous, Dense material
B. Fine particles with a tight arrangement
C. Dense material with void spaces
D. Fine fibers with void spaces
D. fine fibers with void spaces.
Gases do not conduct heat very well because their molecules are relatively far apart.
Good insulators are materials that do not conduct heat well because their physical make-up disrupts the point-to-point transfer of heat or thermal energy.
Ch. 1 Fire Dynamics: Heat Transfer The transfer of thermal energy by the circulation or movement of a fluid (liquid or gas) describes which form of heat transfer? A. Conduction B. Convection C. Radiation D. Thermal
B. Convection
Vertical movement is due to the buoyancy of smoke and fire gasses.
(Horizontal) Lateral movement is usually the result of pressure differences. (movement from high to low pressure)
Ch. 1 Fuel The rate at which energy transfers defines what? A. Heat transfer B. Power C. Thermal conductivity D. oxidation
B. Power
another way to describe power is the rate at which energy converts from one form to another.
The standard International (SI) unit for power is the watt (W)
Ch. 1 Fire dynamics: Liquids \_\_\_\_\_\_\_\_\_ is the minimum temperature at which a liquid gives off sufficient vapors to ignite, but not sustain combustion, in the presence of a piloted ignition source. A. Auto-ignition B. Burn temperature C. Combustion D. Flash point
D. flash point
Fire point- sustains combustion
Liquid fuels that vaporize sufficiently to burn at temperatures under 100 degrees F. present a significant flammability hazard.
Ch. 1 Fire dynamics: oxygen When oxygen concentration is limited, the flaming combustion will diminish, causing combustion to continue in the non-flaming mode. At normal ambient temperatures (68 degrees F.) materials can ignite and burn at oxygen concentrations as low as: A. 15 % B. 17 % C. 19 % D. 21 %.
A. 15%.
Ch. 1 Fire dynamics: Physical science. Energy is the capacity to perform work. Energy is measured in \_\_\_\_\_\_\_\_\_\_. A. Watts B. degrees C. Joules D. BTU's
C. Joules
Ch. 1 Fire dynamics: Rapid Fire development: A rapid fire development that involves more than one compartment of a structure is know as: A. Backdraft B. Flashover C. Smoke Explosion D. Rollover
C. Smoke Explosion
Ch. 1 Fire dynamics:
Failure of Lightweight trusses and joists
Unprotected engineered steel and wooden trusses can fail after five to ten minutes of fire exposure. These trusses can fail from heat alone without flame contact. What is the critical temperature for steel trusses?
A. 785 degrees F.
B. 1000 degrees F.
C. 1100 degrees F.
D. 937 degrees F.
1000 degrees F.
is the temperature at which steel begins to weaken.
Ch. 2. Pre-fire planning United States Construction Building constructed of materials that will not contribute to fire development or spread are classified as what? A. Type I B. Type II C. Type III D. Type IV
B. Type II construction.
Ch. 1 fire dynamics: pg. 34 Liquid fuels that vaporize sufficiently to burn at temperatures under \_\_\_\_\_ present a significant flammability hazard. A. 212 degrees F B. 150 degrees F C. 100 degrees F D. 75 degrees F.
C. 100 degrees F.
Ch 1. Fire Dynamics: Kinetic energy is the energy that a \_\_\_\_\_ object possesses. A. heavy B. Moving C. Stationary D. Dense
B. moving
Ch. 4. pg. 175
When the neutral plane is roughly centered between the ceiling and floor the fire is beginning:
A. to be ventilation controlled
B. to be fuel controlled
C. to change from growth stage to fully developed
D. to self ventilate to the exterior.
A. to be ventilation controlled.
Note: flashover conditions are developing.
Ch. 1 fire dynamics: This toxin is 200 times more effective in combining with blood than oxygen: A. HCN B. CO C. CO2 D. NO2
B. CO carbon monoxide.
created by incomplete combustion of organic material
Ch. 1 pg. 37 An atmosphere is considered oxygen rich when the oxygen level exceeds: A. 21% B. 25% C. 27.5 % D. 23.5%
D. 23.5 %.
Note: oxygen rich environments present an increased fire risk.
Ch. 1 Fire dynamics This toxin is produced from incomplete combustion of organic materials: A. Carbon Monoxide B. Carbon Dioxide C. Hydrogen Cyanide D. Sulfur Dioxide
A. Carbon Monoxide.
200 more times likely to combine with blood than O2.
CH. 1. pg. 40 A fire needs a fuel source, oxygen, heat and a chemical reaction to sustain flaming combustion. other factors that have an impact on the burning fuel are the available ventilation, access to additional fuel and heat losses or gains. These factors are part of the \_\_\_\_\_\_\_\_\_. A. Fire triangle B. Fire source C. Fuel arrangement D. Compartment
D. compartment.
The compartment surrounding that burning fuel has a significant impact.
Ch. 1 pg. 42
The incipient stage is where fire begins. typically fuel controlled. The temperature will continue to rise and the fire has not yet influenced the environment within the compartment to a significant extent. The visual indicator that a fire is leaving the incipient stage is:
A. Smoke level
B. Compartment temperature
C. Flame height
D. percent involvement of the compartment.
C. flame height.
When flames reach 2.5 feet high, radiated heat begins to transfer more heat than convection. The fire will then enter the growth stage.
Ch. 1 pg. 50
Rapid fire development refers to the rapid transition from the growth stage or early decay stage to a ventilation limited, fully developed stage. To protect yourself and your crew, you must be able to: (3)
- recognize the indicators of rapid fire development
- know the conditions created by each of these situations
- determine the best action to take before they occur.
ch 1 pg. 50 The rapid transition from the growth stage to the fully developed stage is know as: A. smoke explosion B. Flashover C. backdraft D. rollover
B. flashover
the gas temperatures in the room reach 1100 degrees F.
the room changes from a two-layer condition to a single well mixed hot gas condition from floor to ceiling.
all materials ignite simultaneously.
Ch. 1 pg. 61 The wind can increase the pressure inside the structure, drive smoke and flames into unburned portions of the structure and onto advancing firefighters. Wind speeds of \_\_\_\_\_\_ can create wind driven fire conditions. A. 10 mph B. 15 mph C. 20 mph D. 25 mph
A. `10 mph.
you must be aware of the wind direction and velocity and use it to your advantage to assist in tactical ventilation.
Ch. 1 pg. 61
Limiting or interrupting one or more of the essential elements in the combustion process depicted in the fire tetrahedron controls and extinguishes fire. Firefighters can influence fire dynamics in a number of ways. (4)
- temperature reductions use water or foam
- Fuel removal -eliminate new sources of fuel. tactics in wildland fires, or liquid and gas fires.
- oxygen exclusion/ flow path.- control doors and using tactical ventilation to control the amount of air available.
- chemical flame inhibition - using extinguishing agents other than water. dry chemical, halons to stop flame production.