This document discusses fire origin and cause determination. It describes the three types of evidence used to indicate the area of origin or cause of a fire: physical evidence, witness statements, and elimination of other ignition sources. Fire investigators decide what evidence and information to collect from the scene. They must also be aware of various legal issues around locating and collecting evidence during an investigation.

1. Essentials of Fire Fighting
6th Edition
Firefighter II
Chapter 19 — Fire Origin and Cause Determination
Describe types of evidence used to
indicate the area of origin or fire cause.
Learning Objective 1
19–2
The three types of evidence are used
to support testimony.
1–3
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REVIEW QUESTION
What types of evidence are used to
indicate an area of origin or a fire’s
cause?
19–4

2. Recognize fire cause evidence.
Learning Objective 2
19–5
Fire investigators decide what evidence
and information is collected.
19–6
(Cont.)
Fire investigators decide what evidence
and information is collected.
19–7
(Cont.)
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Fire investigators decide what evidence
and information is collected.
19–8
(Cont.)
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3. Fire investigators decide what evidence
and information is collected.
19–9
(Cont.)
Fire investigators decide what evidence
and information is collected.
19–10
REVIEW QUESTION
How can a Firefighter II recognize
fire cause evidence?
19–11
Explain the roles and responsibilities
of responders and investigators
involved in fire investigations.
Learning Objective 3
1–12

4. The roles and responsibilities of
responders and investigators vary.
19–13
(Cont.)
The roles and responsibilities of
responders and investigators vary.
19–14
REVIEW QUESTION
Who are the types of responders
and investigators that may be involved in
a fire investigation?
19–15
Tell what legal issues impact location
and collection of evidence during a
fire investigation.
Learning Objective 4
19–16

5. Location and collection of evidence is
based on a variety of laws.
19–17
There are several important legal issues
you should be aware of.
19–18
REVIEW QUESTION
What legal issues impact the location
and collection of evidence during a
fire investigation?
1–19
• When the area of origin is known a
more thorough investigation can be
conducted to determine cause.
• Firefighters may be assigned to assist
with an investigation.
• When origin and cause reveal
incendiary fire property becomes a
crime scene.
Summary
1–20

6. Protect evidence of fire cause and
origin.
This objective is measured in Skill
Sheet 19-II-1.
Learning Objective 5
1–21