NFPA 921 UPDATED EVALUATION 2026 TEST
QUESTIONS AND ANSWERS SURE A+
✔✔3.3.10 Arc Site. - ✔✔The location on a conductor with localized
damage that resulted from an electrical arc.
✔✔3.3.11 Arcing Through Char. - ✔✔Arcing associated with a matrix
of charred material (e.g., charred conductor insulation) that acts as a semi-conductive
medium.
✔✔3.3.12 Area of Origin. - ✔✔A structure, part of a structure, or
general geographic location within a fire scene, in which the "point of origin" of a fire or
explosion is reasonably believed to be located. (See also 3.3.142, Point of Origin.)
✔✔3.3.13 Arrow Pattern. - ✔✔A fire pattern displayed on the cross section
of a burned wooden structural member.
✔✔3.3.14 Arson. - ✔✔The crime of maliciously and intentionally, or
recklessly, starting a fire or causing an explosion.
✔✔3.3.15 Auto ignition. - ✔✔Initiation of combustion by heat but
without a spark or flame.
, ✔✔3.3.16 Autoignition Temperature. - ✔✔The lowest temperature at which a
combustible material ignites in air without a spark orflame.
✔✔3.3.17 Backdraft. - ✔✔A deflagration resulting from the sudden
introduction of air into a confined space containing oxygen deficient products of
incomplete combustion.
✔✔3.3.18 Bead. - ✔✔A rounded globule of re-solidified metal at the
end of the remains of an electrical conductor that was caused by arcing and is
characterized by a sharp line of demarcation between the melted and unmelted
conductor surfaces.
✔✔3.3.19 Blast Pressure Front. - ✔✔The expanding leading edge of an explosion
reaction that separates a major difference in pressure between normal ambient
pressure ahead of the front and potentially damaging high pressure at and behind the
front.
✔✔3.3.20 BLEVE. - ✔✔Boiling liquid expanding vapor explosion.
✔✔3.3.21 Bonding. - ✔✔The permanent joining of metallic parts to
form an electrically conductive path that ensures electrical continuity and the capacity to
conduct safely any current likely to be imposed.
✔✔3.3.22 British Thermal Unit (Btu). - ✔✔The quantity of heat required to raise the
temperature of one pound of water 1°F at
the pressure of 1 atmosphere and temperature of 60°F; a British thermal unit is equal to
1055 joules, 1.055 kilojoules, and 252.15 calories.
✔✔3.3.23 Burning Rate. - ✔✔See 3.3.105, Heat Release Rate (HRR).
✔✔3.3.24* Calcination of Gypsum. - ✔✔A fire effect realized in gypsum products,
including wallboard, as a result of exposure to heat that drives off free and chemically
bound water.
✔✔3.3.25 Calorie. - ✔✔The amount of heat necessary to raise 1 gram
of water 1°C at the pressure of 1 atmosphere and temperature of 15°C; a calorie is
4.184 joules, and there are 252.15 calories in a British thermal unit (Btu).
✔✔3.3.26 Cause. - ✔✔The circumstances, conditions, or agencies that
brought about or resulted in the fire or explosion incident, damage to property resulting
from the fire or explosion incident, or bodily injury or loss of life resulting from the fire or
explosion incident.
✔✔3.3.27 Ceiling Jet. - ✔✔A relatively thin layer of flowing hot gases
QUESTIONS AND ANSWERS SURE A+
✔✔3.3.10 Arc Site. - ✔✔The location on a conductor with localized
damage that resulted from an electrical arc.
✔✔3.3.11 Arcing Through Char. - ✔✔Arcing associated with a matrix
of charred material (e.g., charred conductor insulation) that acts as a semi-conductive
medium.
✔✔3.3.12 Area of Origin. - ✔✔A structure, part of a structure, or
general geographic location within a fire scene, in which the "point of origin" of a fire or
explosion is reasonably believed to be located. (See also 3.3.142, Point of Origin.)
✔✔3.3.13 Arrow Pattern. - ✔✔A fire pattern displayed on the cross section
of a burned wooden structural member.
✔✔3.3.14 Arson. - ✔✔The crime of maliciously and intentionally, or
recklessly, starting a fire or causing an explosion.
✔✔3.3.15 Auto ignition. - ✔✔Initiation of combustion by heat but
without a spark or flame.
, ✔✔3.3.16 Autoignition Temperature. - ✔✔The lowest temperature at which a
combustible material ignites in air without a spark orflame.
✔✔3.3.17 Backdraft. - ✔✔A deflagration resulting from the sudden
introduction of air into a confined space containing oxygen deficient products of
incomplete combustion.
✔✔3.3.18 Bead. - ✔✔A rounded globule of re-solidified metal at the
end of the remains of an electrical conductor that was caused by arcing and is
characterized by a sharp line of demarcation between the melted and unmelted
conductor surfaces.
✔✔3.3.19 Blast Pressure Front. - ✔✔The expanding leading edge of an explosion
reaction that separates a major difference in pressure between normal ambient
pressure ahead of the front and potentially damaging high pressure at and behind the
front.
✔✔3.3.20 BLEVE. - ✔✔Boiling liquid expanding vapor explosion.
✔✔3.3.21 Bonding. - ✔✔The permanent joining of metallic parts to
form an electrically conductive path that ensures electrical continuity and the capacity to
conduct safely any current likely to be imposed.
✔✔3.3.22 British Thermal Unit (Btu). - ✔✔The quantity of heat required to raise the
temperature of one pound of water 1°F at
the pressure of 1 atmosphere and temperature of 60°F; a British thermal unit is equal to
1055 joules, 1.055 kilojoules, and 252.15 calories.
✔✔3.3.23 Burning Rate. - ✔✔See 3.3.105, Heat Release Rate (HRR).
✔✔3.3.24* Calcination of Gypsum. - ✔✔A fire effect realized in gypsum products,
including wallboard, as a result of exposure to heat that drives off free and chemically
bound water.
✔✔3.3.25 Calorie. - ✔✔The amount of heat necessary to raise 1 gram
of water 1°C at the pressure of 1 atmosphere and temperature of 15°C; a calorie is
4.184 joules, and there are 252.15 calories in a British thermal unit (Btu).
✔✔3.3.26 Cause. - ✔✔The circumstances, conditions, or agencies that
brought about or resulted in the fire or explosion incident, damage to property resulting
from the fire or explosion incident, or bodily injury or loss of life resulting from the fire or
explosion incident.
✔✔3.3.27 Ceiling Jet. - ✔✔A relatively thin layer of flowing hot gases
