Quiz 1-14
What is the average number of firefighters killed in the line of duty each year?
100
The NFPA has compiled data on firefighter fatalities since what year?
1970
How many civilians were killed by fires in 2007?
3,430
What is a premixed flame?
A flame where air is introduced before the point of combustion
Which best describes the temperature scale known as Fahrenheit?
A measurement of temperature used most commonly in the U.S. where 32 degrees is the freezing point of water
What is the definition of a sphere?
A perfectly round ball which contains volume
NFPA 921 defines fire as which of the following?
A rapid oxidation process, which is a chemical reaction, resulting in the evolution of heat and light in varying intensities
What is flashover?
A rapidly occurring transitional event in the development of a compartment fire
Which best describes the temperature scale of Kelvin?
A scale using absolute zero, where water freezes at 273.15 and boils at 373.13
What is a coordinate system?
A system which uses X, Y, and Z coordinates
Which best describes the Rankin temperature scale?
A temperature measurement scale where all molecular movement ceases at zero, and water freezes at 491.67
Which best describes the temperature scale of Celsius?
A temperature scale based on the two fixed points of zero as the freezing point of water and 100 the boiling point
An endothermic reaction
Absorbs energy
Examples of explosions involving gases include:
All of the above
Fire prevention professionals involved in inspections are charged with identifying conditions that:
All of the above
Fire protection professionals must utilize a full knowledge of what topics?
All of the above
The fire triangle consists of which of these components?
All of the above
Which of these is not a by-product of combustion?
All of the above are by-products
What is fuel?
An atom or molecule in the gaseous state, within its flammable limits, that is readily able to chemically react with oxygen
Covalent bonds involve
Atoms sharing electrons in their valance orbits
What defines a gaseous state?
Atoms that collide but are not in a fixed arrangement, and assume the shape of a container
The temperature to which a mixture of fuel gas and air must be raised to initiate combustion without any external heat source is called:
Autoignition temperature
Three predictable conditions which lead to firefighter fatalities include flashover, rollover, and what else?
Backdraft
Which of the following is not a method of heat transfer?
Backdraft
Flame spread of the soundproofing used at the Station Nightclub was known to fire-testing agencies and professionals, but was not considered during:
Both A and B
Which of the following is a plausible scenario after ignition has occurred?
Both A and B
The energy required to raise one gram of water one degree centigrade is a:
Calorie
Radiation is defined as the transfer of energy:
Caused by electromagnetic waves
The redirected flow of the buoyancy-driven thermal plume under a ceiling is known as a:
Ceiling jet
What is a laminar flame?
Combustion zones depicted by constant shape and low velocity (i.e., those which have little side-to-side movement)
What are alkanes?
Compounds that contain only single bonds between carbon atoms
FDS Smokeview is what type of model?
Computational fluid dynamics (CFD) or field
What is ignition energy?
Energy required to initiate flame
When the fire reaches a state where sufficient oxygen, fuel, and radiant feedback are available, it has achieved what benchmark?
Established burning
Which of the following is not one of the spread sheets used by the NRC?
Estimation of fire growth curve and buoyancy of plumes produced
Which of these is used to describe only the luminous portions of a plume created by the combustion process?
Flame plume
A Class B fire involves what types of materials?
Flammable gases and flammable or combustible liquids
What is a hazard class under DOT standards?
For the purpose of the DOT regulations, any of the nine categories of hazard assigned to a hazardous material because it complies with defining criteria
What type of fire exists where the amount of fuel available is in a physical state capable of supporting combustion is limited?
Fuel-controlled fire
An exothermic reaction:
Gives off heat
When the fire reaches a state where spread continues through the original fuel package and begins to involve neighboring fuel packages, what has been reached?
Growth phase
The transfer of energy based on a temperature difference between two objects or regions of a single object is termed:
Heat
In regard to the orientation of solid fuels, which will burn slower?
Horizontal
What are alkynes?
Hydrocarbons possessing one or more carbon-to-carbon triple bonds
What are alkenes or olefins?
Hydrocarbons whose molecules contain one or more carbon-to-carbon double bonds
The energy required to initiate a flame is called:
Ignition energy.
Conduction is defined as the transfer of energy:
In the form of heat by direct contact through the excitation of molecules/particles driven by a temperature difference
The predominant factor that led to the large number of deaths at the Cocoanut Grove fire was:
Inward swinging doors
The energy required to move one kilogram one meter per second over a distance of one meter is a:
Joule
What makes up a compound?
Mass comprised of two or more types of chemically connected atoms
Temperature refers to the:
Measurement of the amount of motion that the molecules or atoms have
The least amount of energy required to initiate a flame is called:
Minimum ignition energy
What is ignition temperature?
Minimum temperature required for ignition of fuel gases under specific test conditions
Which of the following is not a material property that influences both ignition and flame spread?
Moisture
A Class C fire involves what types of materials?
Natural and synthetic materials like rubber and plastics, which are energized by electrical circuits, wiring, motors, and other equipment
Electrons are _________ charged
Negatively
Neutrons are _________ charged
Neutrally
A Class A fire involves what types of materials?
Ordinary cellulosic materials such as wood and paper as well as similar natural and synthetic materials like rubber and plastics
Fire investigators are primarily tasked with identifying:
Origin, cause, spread, responsibility, and circumstances
Investigators must first seek the _______ and then the ________ of a fire in order to ascertain what happened
Origin; Cause
What is a turbulent flame?
Oxidation occurring within a generalized area but not in a steady geometric pattern, characterized by whirls
Protons are _________ charged
Positively
What is the term used to describe the evaluation of conditions before emergencies?
Preplanning
The atomic number of an atom is defined by the number of:
Protons
Study of fire dynamics helps to:
Provide safety for humans and structures
Air entrainment is the:
Pulling of cooler air into the fire plume
As altitude changes, the vapor pressure of a liquid:
Remains the same
A BLEVE, or mechanical explosion, is defined by:
Structural failure of a container
The standard time-temperature curve does not take into account what kinds of fuels that are common today?
Synthetic materials
What is the autoignition temperature, (autogenous ignition temperature)?
Temperature at which oxidation reactions will initiate within fuel/air mixtures without an outside pilot source
What is the pilot ignition temperature?
Temperature required to produce the lower flammable limit and can be ignited in the presence of a piloted ignition source
Flammability limits are dependent on which of the following?
Temperature, pressure, and oxygen concentration
What is the effective heat of combustion?
The actual amount of energy that is released when fuel oxidizes in air
Rate refers to:
The amount of energy over time or another unit of measure
A Class K fire involves what types of materials?
The combustion of certain cooking media such as vegetable and animal fats and oils
A Class D fire involves what types of materials?
The combustion of certain metals
What is flameover (rollover)?
The condition whereby unburned fuel (pyrolyzate) from the originating fire has accumulated in the ceiling layer to a sufficient concentration that it ignites and burns
What is circumference?
The distance around a circle
What is a stoichiometric mixture?
The exact proper mixture (mass of each reactant) of chemical for a chemical reaction
What is a chemical explosion?
The generation of high-pressure gas from an exothermic chemical reaction
What is heat flux, (W/m2)?
The heat transfer rate in the x direction per unit area perpendicular to the direction of the transfer
What is the upper explosive limit?
The highest percentage of fuel to air where combustion can occur
What is a backdraft?
The ignition of unburned pyrolyzates due to sudden influx of air which ignites and results in an extremely rapid burning of gases/pyrolysis products being forced out through the opening
What does the term temperature refer to?
The measurement of heat energy
What is the lower flammable limit?
The percentage of air and fuel where the lowest amount of fuel will combust
A suitable definition of a detonation would include which of the following?
The propagation of a combustion zone at a velocity that is greater than the speed of sound in the unreacted medium
What is an atom?
The smallest particle of an element
A flame is defined as:
The visible, luminous body where the oxidation reaction is occurring
What is one factor responsible for the rapid fire development in today's built environment?
The volume of commodities and synthetics
What is the term for solids that absorb heat energy more readily and do not transfer it as quickly through the material to the opposite side?
Thermally thick
What is the term for the inability to absorb heat energy very well, resulting in quickly transferring heat from one side to the opposite side of the material?
Thermally thin
What is the definition of volume?
Three-dimensional measure expressing total space occupied by an object or contained within a compartment and expressed in cubic measure
Convection is defined as the transfer of energy:
Through a circulating fluid to or from a solid object
Ionic bonds involve:
Transfer of electrons from the valence orbit of one atom to fill the valence orbit of another atom.
What is the definition of area?
Two-dimensional measurement to determine quantity of space contained
What term describes the collection of gases by the ceiling and walls which forms a relatively uniform layer throughout the upper levels of the compartment?
Upper layer
The metric system is a system of measurement that:
Utilizes increments of 10
Specific gravity of vapors and gases is termed:
Vapor density
What type of fire exists where fuel is present, but air entrainment is limited?
Ventilation-controlled fire
The English system of measurement:
utilizes inches, feet, and miles.
