IAAI CFI Exam Bank 2026 | IAAI Certified Fire Investigator CFI Exam
Study Guide, IAAI-CFI Certification Exam Prep, Fire Investigation
Practice Questions, NFPA 1033, NFPA 921, Origin & Cause, Fire
Dynamics, Evidence Collection, Fire Scene Investigation, Scientific
Method, Expert Testimony, Practice Questions, Answers & Rationales
Question 1: The fire tetrahedron consists of fuel, oxygen, heat, and which fourth
essential component?
A. Smoke
B. Pressure
C. Ventilation
D. An uninhibited chemical chain reaction
CORRECT ANSWER: D. An uninhibited chemical chain reaction
Rationale: The fire tetrahedron expanded upon the traditional fire triangle by
recognizing the self-sustaining chemical chain reaction as a fourth necessary
element for combustion. This concept is fundamental to understanding fire
behavior and extinguishment methods.
Question 2: Which heat transfer mechanism is primarily responsible for fire
spread to objects not in direct contact with flames, such as across a room prior
to flashover?
A. Conduction
B. Convection
C. Radiation
D. Direct flame contact
CORRECT ANSWER: C. Radiation
Rationale: Radiation transfers heat energy through electromagnetic waves
without requiring a medium. It is the primary mechanism for pre-flashover fire
spread to objects not in direct contact with flames. Conduction requires direct
contact through solids, while convection involves heat transfer through fluids.
Question 3: What is the lowest temperature at which a liquid produces enough
vapor to ignite momentarily in the presence of an ignition source but does not
sustain combustion?
,A. Autoignition temperature
B. Fire point
C. Flash point
D. Ignition temperature
CORRECT ANSWER: C. Flash point
Rationale: The flash point is the minimum temperature at which a liquid gives off
sufficient vapor to form an ignitable mixture with air near the surface. At this
temperature, the vapor will ignite momentarily but will not sustain combustion.
The fire point is higher and sustains combustion.
Question 4: A liquid with a flash point above 100°F is classified as:
A. Flammable liquid
B. Combustible liquid
C. Volatile liquid
D. Hazardous liquid
CORRECT ANSWER: B. Combustible liquid
Rationale: Combustible liquids are defined as having a flash point at or above
100°F (37.8°C). This distinguishes them from flammable liquids, which have flash
points below 100°F.
Question 5: Flashover occurs when:
A. All combustible surfaces in a compartment simultaneously ignite
B. The fire transitions from smoldering to flaming combustion
C. The oxygen concentration drops below 15%
D. The ceiling temperature reaches 212°F
CORRECT ANSWER: A. All combustible surfaces in a compartment
simultaneously ignite
Rationale: Flashover is the transition from a localized fire to full-room
involvement where all exposed combustible surfaces simultaneously ignite. This
typically occurs when upper layer temperatures reach approximately 500-600°C
(932-1112°F).
,Question 6: What temperature in the upper gas layer causes the onset of
flashover?
A. 900°F
B. 1100°F
C. 1500°F
D. 2000°F
CORRECT ANSWER: B. 1100°F
Rationale: The onset of flashover occurs when the upper gas layer temperature
reaches approximately 1100°F (593°C). At this point, radiant heat flux to the floor
reaches about 2 W/cm², causing simultaneous ignition of all combustible
materials in the compartment.
Question 7: The measurement of radiant heat flux from the gas layer to the
floor that indicates the onset of flashover is:
A. 1 W/cm²
B. 2 W/cm²
C. 5 W/cm²
D. 10 W/cm²
CORRECT ANSWER: B. 2 W/cm²
Rationale: A heat flux of approximately 2 W/cm² is the critical threshold for the
onset of flashover. At this level, radiant heat from the upper gas layer is sufficient
to ignite all combustibles in the compartment.
Question 8: The process by which a solid fuel decomposes under the action of
heat to produce gaseous fuels is known as:
A. Vaporization
B. Sublimation
C. Pyrolysis
D. Oxidation
CORRECT ANSWER: C. Pyrolysis
Rationale: Pyrolysis is the thermal decomposition of solid materials at elevated
temperatures in the absence of oxygen, producing volatile gases that can
, subsequently ignite. Vaporization applies to liquids, and sublimation is a phase
change from solid to gas.
Question 9: Which of the following is considered a Class A fire?
A. Cooking oil fire
B. Energized electrical equipment fire
C. Wood pallet fire
D. Magnesium fire
CORRECT ANSWER: C. Wood pallet fire
Rationale: Class A fires involve ordinary combustibles such as wood, paper, cloth,
rubber, and certain plastics. Cooking oils are Class K, electrical fires are Class C,
and magnesium is a Class D combustible metal.
Question 10: Carbon monoxide binds with hemoglobin in the blood
approximately how many times greater than oxygen?
A. 50 times
B. 100 times
C. 250 times
D. 500 times
CORRECT ANSWER: C. 250 times
Rationale: Carbon monoxide binds with hemoglobin approximately 250 times
greater than oxygen, which is why CO is a significant fire-related hazard. This
binding prevents oxygen transport in the bloodstream.
Question 11: The temperature scale based on the lowest possible temperature
of absolute zero is called:
A. Celsius
B. Fahrenheit
C. Kelvin
D. Rankine
CORRECT ANSWER: C. Kelvin
Study Guide, IAAI-CFI Certification Exam Prep, Fire Investigation
Practice Questions, NFPA 1033, NFPA 921, Origin & Cause, Fire
Dynamics, Evidence Collection, Fire Scene Investigation, Scientific
Method, Expert Testimony, Practice Questions, Answers & Rationales
Question 1: The fire tetrahedron consists of fuel, oxygen, heat, and which fourth
essential component?
A. Smoke
B. Pressure
C. Ventilation
D. An uninhibited chemical chain reaction
CORRECT ANSWER: D. An uninhibited chemical chain reaction
Rationale: The fire tetrahedron expanded upon the traditional fire triangle by
recognizing the self-sustaining chemical chain reaction as a fourth necessary
element for combustion. This concept is fundamental to understanding fire
behavior and extinguishment methods.
Question 2: Which heat transfer mechanism is primarily responsible for fire
spread to objects not in direct contact with flames, such as across a room prior
to flashover?
A. Conduction
B. Convection
C. Radiation
D. Direct flame contact
CORRECT ANSWER: C. Radiation
Rationale: Radiation transfers heat energy through electromagnetic waves
without requiring a medium. It is the primary mechanism for pre-flashover fire
spread to objects not in direct contact with flames. Conduction requires direct
contact through solids, while convection involves heat transfer through fluids.
Question 3: What is the lowest temperature at which a liquid produces enough
vapor to ignite momentarily in the presence of an ignition source but does not
sustain combustion?
,A. Autoignition temperature
B. Fire point
C. Flash point
D. Ignition temperature
CORRECT ANSWER: C. Flash point
Rationale: The flash point is the minimum temperature at which a liquid gives off
sufficient vapor to form an ignitable mixture with air near the surface. At this
temperature, the vapor will ignite momentarily but will not sustain combustion.
The fire point is higher and sustains combustion.
Question 4: A liquid with a flash point above 100°F is classified as:
A. Flammable liquid
B. Combustible liquid
C. Volatile liquid
D. Hazardous liquid
CORRECT ANSWER: B. Combustible liquid
Rationale: Combustible liquids are defined as having a flash point at or above
100°F (37.8°C). This distinguishes them from flammable liquids, which have flash
points below 100°F.
Question 5: Flashover occurs when:
A. All combustible surfaces in a compartment simultaneously ignite
B. The fire transitions from smoldering to flaming combustion
C. The oxygen concentration drops below 15%
D. The ceiling temperature reaches 212°F
CORRECT ANSWER: A. All combustible surfaces in a compartment
simultaneously ignite
Rationale: Flashover is the transition from a localized fire to full-room
involvement where all exposed combustible surfaces simultaneously ignite. This
typically occurs when upper layer temperatures reach approximately 500-600°C
(932-1112°F).
,Question 6: What temperature in the upper gas layer causes the onset of
flashover?
A. 900°F
B. 1100°F
C. 1500°F
D. 2000°F
CORRECT ANSWER: B. 1100°F
Rationale: The onset of flashover occurs when the upper gas layer temperature
reaches approximately 1100°F (593°C). At this point, radiant heat flux to the floor
reaches about 2 W/cm², causing simultaneous ignition of all combustible
materials in the compartment.
Question 7: The measurement of radiant heat flux from the gas layer to the
floor that indicates the onset of flashover is:
A. 1 W/cm²
B. 2 W/cm²
C. 5 W/cm²
D. 10 W/cm²
CORRECT ANSWER: B. 2 W/cm²
Rationale: A heat flux of approximately 2 W/cm² is the critical threshold for the
onset of flashover. At this level, radiant heat from the upper gas layer is sufficient
to ignite all combustibles in the compartment.
Question 8: The process by which a solid fuel decomposes under the action of
heat to produce gaseous fuels is known as:
A. Vaporization
B. Sublimation
C. Pyrolysis
D. Oxidation
CORRECT ANSWER: C. Pyrolysis
Rationale: Pyrolysis is the thermal decomposition of solid materials at elevated
temperatures in the absence of oxygen, producing volatile gases that can
, subsequently ignite. Vaporization applies to liquids, and sublimation is a phase
change from solid to gas.
Question 9: Which of the following is considered a Class A fire?
A. Cooking oil fire
B. Energized electrical equipment fire
C. Wood pallet fire
D. Magnesium fire
CORRECT ANSWER: C. Wood pallet fire
Rationale: Class A fires involve ordinary combustibles such as wood, paper, cloth,
rubber, and certain plastics. Cooking oils are Class K, electrical fires are Class C,
and magnesium is a Class D combustible metal.
Question 10: Carbon monoxide binds with hemoglobin in the blood
approximately how many times greater than oxygen?
A. 50 times
B. 100 times
C. 250 times
D. 500 times
CORRECT ANSWER: C. 250 times
Rationale: Carbon monoxide binds with hemoglobin approximately 250 times
greater than oxygen, which is why CO is a significant fire-related hazard. This
binding prevents oxygen transport in the bloodstream.
Question 11: The temperature scale based on the lowest possible temperature
of absolute zero is called:
A. Celsius
B. Fahrenheit
C. Kelvin
D. Rankine
CORRECT ANSWER: C. Kelvin
