NFPA 921 EXAM WITH CORRECT ACTUAL
QUESTIONS AND CORRECTLY WELL
DEFINED ANSWERS LATEST 2025 ALREADY
GRADED A+
Heat and Flame Vector Analysis - ANSWERS-A process to assist with fire spread
analysis and origin determination in which arrows representing the
investigator's assessment of the direction of heat/flame spread are placed on a
detailed diagram of the fire scene. The patterns can be traced back to the fire
origin.
Isochars - ANSWERS-Points of equal char depths
The pressure required to reach the line of demarcation where calcined and
virgin gypsum meet - ANSWERS-800 to 900g/mm2 (1120 to 1270 psi)
Depth of calcination grid survey in increments of - ANSWERS-0.3m (1ft) or less
Eutectic Melting - ANSWERS-Alloying of metals
,One of the most important fire dynamics considerations is? - ANSWERS-The
availability of oxygen.
Origin Matrix Analysis - ANSWERS-Divide each compartment into volumes, and
then consider the extent of the damage expected before and at flashover.
Negative Corpus - ANSWERS-Identifying the ignition source for a fire by
believing to have eliminated all ig nation sources found, known, or suspected to
have been present in the area of origin, and for which no supporting evidence
exists.
Complete burnout is also known as - ANSWERS-Black hole
Deductive reasoning - ANSWERS-Test the hypothesis.
Two Levels of Certainty - ANSWERS-Probable
Possible
Probable Certainty - ANSWERS-More likely true than not. The likelihood of the
hypothesis being true is greater than 50 percent.
Inductive reasoning - ANSWERS-Develop a hypothesis.
, Expectation Bias - ANSWERS-Investigators reach a premature conclusion
without having examined or considered all of the relevant data.
Confirmation Bias - ANSWERS-Investigator relies exclusively on data that
supports the hypothesis and fails to look for, ignores, or dismisses contradictory
or nonsupporting data.
Possible Certainty - ANSWERS-The hypothesis can be demonstrated to be
feasible but cannot be declared probable. If two or more hypothesis are equally
likely, then the level of certainty must be "possible."
Flammable Range of Hydrogen - ANSWERS-71 percent (4% to 75%)
Thermal Conductivity (k) - ANSWERS-A measure of the amount of heat that will
flow across a unit area with a temperature gradient of 1 degree per unit of
length (W/m-K, Btu/hr-ft-F).
Heat Capacity (c)(specific heat) - ANSWERS-A measure of the amount of heat
necessary to raise the temperature of a unit of mass 1 degree, under specific
conditions (J/kg-K, Btu/lb-F).
Normal Ambient Temperature - ANSWERS-20 C, (68 F)
QUESTIONS AND CORRECTLY WELL
DEFINED ANSWERS LATEST 2025 ALREADY
GRADED A+
Heat and Flame Vector Analysis - ANSWERS-A process to assist with fire spread
analysis and origin determination in which arrows representing the
investigator's assessment of the direction of heat/flame spread are placed on a
detailed diagram of the fire scene. The patterns can be traced back to the fire
origin.
Isochars - ANSWERS-Points of equal char depths
The pressure required to reach the line of demarcation where calcined and
virgin gypsum meet - ANSWERS-800 to 900g/mm2 (1120 to 1270 psi)
Depth of calcination grid survey in increments of - ANSWERS-0.3m (1ft) or less
Eutectic Melting - ANSWERS-Alloying of metals
,One of the most important fire dynamics considerations is? - ANSWERS-The
availability of oxygen.
Origin Matrix Analysis - ANSWERS-Divide each compartment into volumes, and
then consider the extent of the damage expected before and at flashover.
Negative Corpus - ANSWERS-Identifying the ignition source for a fire by
believing to have eliminated all ig nation sources found, known, or suspected to
have been present in the area of origin, and for which no supporting evidence
exists.
Complete burnout is also known as - ANSWERS-Black hole
Deductive reasoning - ANSWERS-Test the hypothesis.
Two Levels of Certainty - ANSWERS-Probable
Possible
Probable Certainty - ANSWERS-More likely true than not. The likelihood of the
hypothesis being true is greater than 50 percent.
Inductive reasoning - ANSWERS-Develop a hypothesis.
, Expectation Bias - ANSWERS-Investigators reach a premature conclusion
without having examined or considered all of the relevant data.
Confirmation Bias - ANSWERS-Investigator relies exclusively on data that
supports the hypothesis and fails to look for, ignores, or dismisses contradictory
or nonsupporting data.
Possible Certainty - ANSWERS-The hypothesis can be demonstrated to be
feasible but cannot be declared probable. If two or more hypothesis are equally
likely, then the level of certainty must be "possible."
Flammable Range of Hydrogen - ANSWERS-71 percent (4% to 75%)
Thermal Conductivity (k) - ANSWERS-A measure of the amount of heat that will
flow across a unit area with a temperature gradient of 1 degree per unit of
length (W/m-K, Btu/hr-ft-F).
Heat Capacity (c)(specific heat) - ANSWERS-A measure of the amount of heat
necessary to raise the temperature of a unit of mass 1 degree, under specific
conditions (J/kg-K, Btu/lb-F).
Normal Ambient Temperature - ANSWERS-20 C, (68 F)
