Fire Investigator: Principles and Practice to NFPA 921
and 1033, FIFTH Edition. With complete solution RATED
A+ 2026
Accelerant - Ans Any fuel or oxidizer, often an ignitable liquid, used to initiate a fire or increase
the rate of growth or speed the spread of fire.
Accidental Fires - Ans Fires for which the proven cause does not involve an intentional human
act to ignite or spread fire into an area where the fire should not be.
Accommodation Space - Ans A space on a vessel designed for people to live in.
Active Fire Protection System - Ans Any type of fire protection system that automatically
activates upon detection of a fire condition.
Addressable Technology - Ans Fire alarm and detection systems in which devices and system
components are assigned a data address, are capable of two-way communication, and can
perform certain activities based on signal input.
Adolescent Firesetters - Ans Adolescents, ages 14 to 16 years, who are often responsible for
fires that occur at places other than their homes.
Adrift - Ans Loose, not on moorings or towline.
Aerial Fuels - Ans All green or dead materials located in the forest canopy.
,Affidavit - Ans A voluntary written statement of fact or opinion made under oath and signed
by the author.
Afloat - Ans Floating in water; not sinking.
Air Drop - Ans The aerial application of water, foam, or retardant mixture directly onto the fire
or threatened area or along a strategic position ahead of the fire.
Air Entrainment - Ans The process of air or gases being drawn into a fire, plume, or jet.
Air Sampling Smoke Detection - Ans A method of smoke detection designed to draw air from
the protected area into a detection chamber for analysis.
Alarm Pressure Switch - Ans A type of initiating device installed on all types of wet-based fire
suppression systems; the device initiates a fire alarm signal once a water pressure threshold is
met.
Alarm Signal - Ans A warning signal that alerts occupants of a fire emergency.
Alloying - Ans The mixture of two or more metals in which one or more of the metals is in a
liquefied state.
Alternating Current (AC) - Ans The voltage varies in time with a sine wave at 60 cycles per
second. A sine-wave current results if the load is resistive.
Ambient Temperature - Ans Air temperature of the surrounding environment.
, Ampacity - Ans The current, in amperes, that a conductor can carry continuously under the
conditions of use without exceeding its temperature rating.
Amperage - Ans The unit of electric current that is equivalent to a flow of one coulomb per
second; one coulomb is defined as 6.24 x 10^18 (18th power) electrons.
Annunciation Panel - Ans A device that uses indicating lamps, alphanumeric displays, or other
means to provide first responders with status, condition, and location information concerning
fire alarm system components and devices.
Arc Mapping - Ans The analysis of the locations where electrical arcing has caused damage
and the documentation of the involved electrical circuits.
Arc Survey Diagrams - Ans Locations of electrical arcing are identified and plotted on a
diagram of the affected area of the structure. The spatial relationship of the arc sites can create
a pattern and help establish the sequence of damage. This analysis can be used on building
circuits and electrical devices within a compartment to help identify or narrow the area of
origin.
Arc Tube - Ans A cylinder of fused silica/quartz with electrodes at either end that is used in
most mercury and metal halide lamps.
Arc - Ans A high-temperature luminous electric discharge across a gap where the conductor is
missing or through a medium such as charred insulation.
Arced and Severed - Ans Occurs when wires are arced off on the ends and possible segmented
wires result.
Arc-Fault Circuit Interrupter (AFCI) - Ans Designed to protect against fires caused by arcing
faults in home electrical wiring. The circuitry continuously monitors current flow.
, Area of Origin - Ans The room, building, or general area in which the point of origin is located.
Arson - Ans The crime of maliciously and intentionally, or recklessly, starting a fire or causing
an explosion. Legal definitions of "arson" are defined by statues and judicial decisions that vary
among jurisdictions.
Aspect - Ans The direction the slope faces (N, E, S, W).
Assemblies - Ans Manufactured parts put together to make a completed product.
Autoignition Temperature (AIT) - Ans The lowest temperature at which a combustible material
ignites in air without a spark or flame.
Backflow Valve - Ans Prevents gas from re-entering a container or combustion system.
Balanced Pressure Proportioner - Ans A proportioner that uses an atmospheric tank and pump
to introduce the foam concentrate into the system with the water supply.
Balloon Frame Construction - Ans A construction type in which the exterior wall studs go from
the foundation wall to the roofline. The floor joists are attached to the walls by the use of a
ribbon board, which creates an open stud channel between floors, including the basement and
attic.
Bar Holes - Ans Holes driven into the surface of the ground or pavement with either weighted
metal bars or drills. Gas detectors are then inserted into the holes in order to detect the
location of a gas leak.
and 1033, FIFTH Edition. With complete solution RATED
A+ 2026
Accelerant - Ans Any fuel or oxidizer, often an ignitable liquid, used to initiate a fire or increase
the rate of growth or speed the spread of fire.
Accidental Fires - Ans Fires for which the proven cause does not involve an intentional human
act to ignite or spread fire into an area where the fire should not be.
Accommodation Space - Ans A space on a vessel designed for people to live in.
Active Fire Protection System - Ans Any type of fire protection system that automatically
activates upon detection of a fire condition.
Addressable Technology - Ans Fire alarm and detection systems in which devices and system
components are assigned a data address, are capable of two-way communication, and can
perform certain activities based on signal input.
Adolescent Firesetters - Ans Adolescents, ages 14 to 16 years, who are often responsible for
fires that occur at places other than their homes.
Adrift - Ans Loose, not on moorings or towline.
Aerial Fuels - Ans All green or dead materials located in the forest canopy.
,Affidavit - Ans A voluntary written statement of fact or opinion made under oath and signed
by the author.
Afloat - Ans Floating in water; not sinking.
Air Drop - Ans The aerial application of water, foam, or retardant mixture directly onto the fire
or threatened area or along a strategic position ahead of the fire.
Air Entrainment - Ans The process of air or gases being drawn into a fire, plume, or jet.
Air Sampling Smoke Detection - Ans A method of smoke detection designed to draw air from
the protected area into a detection chamber for analysis.
Alarm Pressure Switch - Ans A type of initiating device installed on all types of wet-based fire
suppression systems; the device initiates a fire alarm signal once a water pressure threshold is
met.
Alarm Signal - Ans A warning signal that alerts occupants of a fire emergency.
Alloying - Ans The mixture of two or more metals in which one or more of the metals is in a
liquefied state.
Alternating Current (AC) - Ans The voltage varies in time with a sine wave at 60 cycles per
second. A sine-wave current results if the load is resistive.
Ambient Temperature - Ans Air temperature of the surrounding environment.
, Ampacity - Ans The current, in amperes, that a conductor can carry continuously under the
conditions of use without exceeding its temperature rating.
Amperage - Ans The unit of electric current that is equivalent to a flow of one coulomb per
second; one coulomb is defined as 6.24 x 10^18 (18th power) electrons.
Annunciation Panel - Ans A device that uses indicating lamps, alphanumeric displays, or other
means to provide first responders with status, condition, and location information concerning
fire alarm system components and devices.
Arc Mapping - Ans The analysis of the locations where electrical arcing has caused damage
and the documentation of the involved electrical circuits.
Arc Survey Diagrams - Ans Locations of electrical arcing are identified and plotted on a
diagram of the affected area of the structure. The spatial relationship of the arc sites can create
a pattern and help establish the sequence of damage. This analysis can be used on building
circuits and electrical devices within a compartment to help identify or narrow the area of
origin.
Arc Tube - Ans A cylinder of fused silica/quartz with electrodes at either end that is used in
most mercury and metal halide lamps.
Arc - Ans A high-temperature luminous electric discharge across a gap where the conductor is
missing or through a medium such as charred insulation.
Arced and Severed - Ans Occurs when wires are arced off on the ends and possible segmented
wires result.
Arc-Fault Circuit Interrupter (AFCI) - Ans Designed to protect against fires caused by arcing
faults in home electrical wiring. The circuitry continuously monitors current flow.
, Area of Origin - Ans The room, building, or general area in which the point of origin is located.
Arson - Ans The crime of maliciously and intentionally, or recklessly, starting a fire or causing
an explosion. Legal definitions of "arson" are defined by statues and judicial decisions that vary
among jurisdictions.
Aspect - Ans The direction the slope faces (N, E, S, W).
Assemblies - Ans Manufactured parts put together to make a completed product.
Autoignition Temperature (AIT) - Ans The lowest temperature at which a combustible material
ignites in air without a spark or flame.
Backflow Valve - Ans Prevents gas from re-entering a container or combustion system.
Balanced Pressure Proportioner - Ans A proportioner that uses an atmospheric tank and pump
to introduce the foam concentrate into the system with the water supply.
Balloon Frame Construction - Ans A construction type in which the exterior wall studs go from
the foundation wall to the roofline. The floor joists are attached to the walls by the use of a
ribbon board, which creates an open stud channel between floors, including the basement and
attic.
Bar Holes - Ans Holes driven into the surface of the ground or pavement with either weighted
metal bars or drills. Gas detectors are then inserted into the holes in order to detect the
location of a gas leak.
