NAFI CFEI Fire Investigation Exam 2026 Certified Fire & Explosion
Investigator Practice Questions & Verified Answers.
Domain Content Area Approximate %
I Fire Science & Chemistry 15%
II Fire Scene Investigation Methodology 25%
III Fire Patterns & Damage Analysis 20%
IV Evidence Collection & Preservation 15%
V Origin & Cause Determination 15%
VI Legal & Professional Responsibilities 10%
Part 1: Fire Science & Chemistry (Questions 1-30)
Question 1
The fire tetrahedron consists of which four elements?
A) Fuel, oxygen, heat, and carbon dioxide
B) Fuel, oxygen, heat, and an uninhibited chemical chain reaction
C) Fuel, oxygen, ignition source, and water
D) Fuel, heat, light, and smoke
,Answer: B
Rationale: The fire tetrahedron expands on the original fire triangle (fuel, oxygen,
heat) by adding the fourth element—an uninhibited chemical chain reaction. This
chain reaction sustains combustion by propagating free radicals. Remove any one
element, and the fire cannot sustain itself .
Question 2
The process by which a solid fuel is converted to a flammable gas is called:
A) Sublimation
B) Pyrolysis
C) Vaporization
D) Oxidation
Answer: B
Rationale: Pyrolysis is the chemical decomposition of a solid material through the
application of heat, producing flammable gases that can then combust. This is
distinct from vaporization (liquid to gas) and sublimation (solid to gas without
liquid phase) .
,Question 3
The lowest temperature at which a liquid produces enough vapor to momentarily
ignite (flash) when an ignition source is introduced is the:
A) Fire point
B) Autoignition temperature
C) Flash point
D) Boiling point
Answer: C
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. The fire
point (A) is the temperature at which sustained combustion occurs, which is
typically higher than the flash point .
Question 4
The process by which heat is transferred through direct contact of materials is
called:
, A) Conduction
B) Convection
C) Radiation
D) Pyrolysis
Answer: A
Rationale: Conduction transfers heat through direct molecular contact within a
material or between touching materials (e.g., heat traveling through a metal
pipe). Convection transfers heat through fluid movement (liquids/gases), while
radiation transfers heat via electromagnetic waves .
Question 5
The temperature at which a material self-ignites without an external ignition
source is the:
A) Flash point
B) Fire point
C) Autoignition temperature
Investigator Practice Questions & Verified Answers.
Domain Content Area Approximate %
I Fire Science & Chemistry 15%
II Fire Scene Investigation Methodology 25%
III Fire Patterns & Damage Analysis 20%
IV Evidence Collection & Preservation 15%
V Origin & Cause Determination 15%
VI Legal & Professional Responsibilities 10%
Part 1: Fire Science & Chemistry (Questions 1-30)
Question 1
The fire tetrahedron consists of which four elements?
A) Fuel, oxygen, heat, and carbon dioxide
B) Fuel, oxygen, heat, and an uninhibited chemical chain reaction
C) Fuel, oxygen, ignition source, and water
D) Fuel, heat, light, and smoke
,Answer: B
Rationale: The fire tetrahedron expands on the original fire triangle (fuel, oxygen,
heat) by adding the fourth element—an uninhibited chemical chain reaction. This
chain reaction sustains combustion by propagating free radicals. Remove any one
element, and the fire cannot sustain itself .
Question 2
The process by which a solid fuel is converted to a flammable gas is called:
A) Sublimation
B) Pyrolysis
C) Vaporization
D) Oxidation
Answer: B
Rationale: Pyrolysis is the chemical decomposition of a solid material through the
application of heat, producing flammable gases that can then combust. This is
distinct from vaporization (liquid to gas) and sublimation (solid to gas without
liquid phase) .
,Question 3
The lowest temperature at which a liquid produces enough vapor to momentarily
ignite (flash) when an ignition source is introduced is the:
A) Fire point
B) Autoignition temperature
C) Flash point
D) Boiling point
Answer: C
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. The fire
point (A) is the temperature at which sustained combustion occurs, which is
typically higher than the flash point .
Question 4
The process by which heat is transferred through direct contact of materials is
called:
, A) Conduction
B) Convection
C) Radiation
D) Pyrolysis
Answer: A
Rationale: Conduction transfers heat through direct molecular contact within a
material or between touching materials (e.g., heat traveling through a metal
pipe). Convection transfers heat through fluid movement (liquids/gases), while
radiation transfers heat via electromagnetic waves .
Question 5
The temperature at which a material self-ignites without an external ignition
source is the:
A) Flash point
B) Fire point
C) Autoignition temperature
