Fire Investigator: Principles and
Practice to NFPA 921 and 1033, Fourth
Edition Exam 2025 Questions and
Answers
Accelerant - ANSWER✔✔-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 - ANSWER✔✔-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 - ANSWER✔✔-A space on a vessel designed for people to live in.
Active Fire Protection System - ANSWER✔✔-Any type of fire protection system that automatically
activates upon detection of a fire condition.
Addressable Technology - ANSWER✔✔-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.
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 1
,Adolescent Firesetters - ANSWER✔✔-Adolescents, ages 14 to 16 years, who are often responsible
for fires that occur at places other than their homes.
Adrift - ANSWER✔✔-Loose, not on moorings or towline.
Aerial Fuels - ANSWER✔✔-All green or dead materials located in the forest canopy.
Affidavit - ANSWER✔✔-A voluntary written statement of fact or opinion made under oath and
signed by the author.
Afloat - ANSWER✔✔-Floating in water; not sinking.
Air Drop - ANSWER✔✔-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 - ANSWER✔✔-The process of air or gases being drawn into a fire, plume, or jet.
Air Sampling Smoke Detection - ANSWER✔✔-A method of smoke detection designed to draw air
from the protected area into a detection chamber for analysis.
Alarm Pressure Switch - ANSWER✔✔-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 - ANSWER✔✔-A warning signal that alerts occupants of a fire emergency.
Alloying - ANSWER✔✔-The mixture of two or more metals in which one or more of the metals is
in a liquefied state.
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 2
,Alternating Current (AC) - ANSWER✔✔-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 - ANSWER✔✔-Air temperature of the surrounding environment.
Ampacity - ANSWER✔✔-The current, in amperes, that a conductor can carry continuously under
the conditions of use without exceeding its temperature rating.
Amperage - ANSWER✔✔-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 - ANSWER✔✔-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 - ANSWER✔✔-The analysis of the locations where electrical arcing has caused
damage and the documentation of the involved electrical circuits.
Arc Survey Diagrams - ANSWER✔✔-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 - ANSWER✔✔-A cylinder of fused silica/quartz with electrodes at either end that is used
in most mercury and metal halide lamps.
Arc - ANSWER✔✔-A high-temperature luminous electric discharge across a gap where the
conductor is missing or through a medium such as charred insulation.
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 3
, Arced and Severed - ANSWER✔✔-Occurs when wires are arced off on the ends and possible
segmented wires result.
Arc-Fault Circuit Interrupter (AFCI) - ANSWER✔✔-Designed to protect against fires caused by
arcing faults in home electrical wiring. The circuitry continuously monitors current flow.
Area of Origin - ANSWER✔✔-The room, building, or general area in which the point of origin is
located.
Arson - ANSWER✔✔-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 - ANSWER✔✔-The direction the slope faces (N, E, S, W).
Assemblies - ANSWER✔✔-Manufactured parts put together to make a completed product.
Autoignition Temperature (AIT) - ANSWER✔✔-The lowest temperature at which a combustible
material ignites in air without a spark or flame.
Backflow Valve - ANSWER✔✔-Prevents gas from re-entering a container or combustion system.
Balanced Pressure Proportioner - ANSWER✔✔-A proportioner that uses an atmospheric tank and
pump to introduce the foam concentrate into the system with the water supply.
Balloon Frame Construction - ANSWER✔✔-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.
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 4
Practice to NFPA 921 and 1033, Fourth
Edition Exam 2025 Questions and
Answers
Accelerant - ANSWER✔✔-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 - ANSWER✔✔-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 - ANSWER✔✔-A space on a vessel designed for people to live in.
Active Fire Protection System - ANSWER✔✔-Any type of fire protection system that automatically
activates upon detection of a fire condition.
Addressable Technology - ANSWER✔✔-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.
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 1
,Adolescent Firesetters - ANSWER✔✔-Adolescents, ages 14 to 16 years, who are often responsible
for fires that occur at places other than their homes.
Adrift - ANSWER✔✔-Loose, not on moorings or towline.
Aerial Fuels - ANSWER✔✔-All green or dead materials located in the forest canopy.
Affidavit - ANSWER✔✔-A voluntary written statement of fact or opinion made under oath and
signed by the author.
Afloat - ANSWER✔✔-Floating in water; not sinking.
Air Drop - ANSWER✔✔-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 - ANSWER✔✔-The process of air or gases being drawn into a fire, plume, or jet.
Air Sampling Smoke Detection - ANSWER✔✔-A method of smoke detection designed to draw air
from the protected area into a detection chamber for analysis.
Alarm Pressure Switch - ANSWER✔✔-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 - ANSWER✔✔-A warning signal that alerts occupants of a fire emergency.
Alloying - ANSWER✔✔-The mixture of two or more metals in which one or more of the metals is
in a liquefied state.
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 2
,Alternating Current (AC) - ANSWER✔✔-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 - ANSWER✔✔-Air temperature of the surrounding environment.
Ampacity - ANSWER✔✔-The current, in amperes, that a conductor can carry continuously under
the conditions of use without exceeding its temperature rating.
Amperage - ANSWER✔✔-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 - ANSWER✔✔-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 - ANSWER✔✔-The analysis of the locations where electrical arcing has caused
damage and the documentation of the involved electrical circuits.
Arc Survey Diagrams - ANSWER✔✔-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 - ANSWER✔✔-A cylinder of fused silica/quartz with electrodes at either end that is used
in most mercury and metal halide lamps.
Arc - ANSWER✔✔-A high-temperature luminous electric discharge across a gap where the
conductor is missing or through a medium such as charred insulation.
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 3
, Arced and Severed - ANSWER✔✔-Occurs when wires are arced off on the ends and possible
segmented wires result.
Arc-Fault Circuit Interrupter (AFCI) - ANSWER✔✔-Designed to protect against fires caused by
arcing faults in home electrical wiring. The circuitry continuously monitors current flow.
Area of Origin - ANSWER✔✔-The room, building, or general area in which the point of origin is
located.
Arson - ANSWER✔✔-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 - ANSWER✔✔-The direction the slope faces (N, E, S, W).
Assemblies - ANSWER✔✔-Manufactured parts put together to make a completed product.
Autoignition Temperature (AIT) - ANSWER✔✔-The lowest temperature at which a combustible
material ignites in air without a spark or flame.
Backflow Valve - ANSWER✔✔-Prevents gas from re-entering a container or combustion system.
Balanced Pressure Proportioner - ANSWER✔✔-A proportioner that uses an atmospheric tank and
pump to introduce the foam concentrate into the system with the water supply.
Balloon Frame Construction - ANSWER✔✔-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.
FOR STUDY PURPOSES ONLY COPYRIGHT © 2025 ALL RIGHTS RESERVED 4
