Origin Cause and Determination

Question 1

What are the four basic steps in determining area of origin?

Answer 1

• Examine exterior
• Examine interior
• Interview witnesses
• Analyze info

Question 2

What is standard is Guide for Fire and Explosion Investigating?

Answer 2

NFPA 921

Question 3

What are some typical fire pattern types?

Answer 3

Plume generated
Hot gas layer
Ventilation generated
Suppression generated
Full room involvement
Clean burns
Pointers or arrows
Irregular patterns
Saddle burns
Protected areas

Question 4

What are saddle burns?

Answer 4

saddle shaped patterns burning downward above the joists

Question 5

The area of greatest damage may be at or near the area of origin. However, the area of origin is a ______ that must be tested.

Answer 5

hypothesis

Question 6

The vehicle fire scene can be divided into three areas for examination:

Answer 6

• scene around vehicle
• exterior
• interior

Question 7

When investigating a fire in the interior of vehicle, how can the compartments be divided up?

Answer 7

• engine
• cargo
• passenger (divided even further in needed)

Question 8

What are some vehicle investigation hazards?

Answer 8

Trip hazards
Spilled liquids
Vehicle stability
Broken glass
Unburned furl
Sharp edges
Airborne articulates
Undeployed air bags
High voltage batteries
Alternative fuels

Question 9

What is white ash in wildland fire investigation a sign of?

Answer 9

More complete combustion and appears on exposed sides

Question 10

What does damage to the top of the section of the windshield possibly indicate?

Answer 10

Fie spread form passenger compartment into engine

Question 11

The area of origin of a wildland fire may display evidence of _____ than at the head of fire.

Answer 11

slower and less intense fire growth

Question 12

How else might the area of origin look compared to head?

Answer 12

More unburned materials at AOO
Effects of flames considerable less at AOO
If brush pile out of control, could be more intense burning there

Question 13

A competent ignition source must have what three qualities?

Answer 13

• sufficient temperature to ignite first material
• sufficient heat energy transfer to result in ignition for first material
• sufficient time to transfer required heat to first material

Question 14

The material first ignited must have what three characteristics?

Answer 14

• capable of being ignited by heat energy from IS
• close enough to receive energy transfer from IS
• capable of absorbing and retaining sufficient heat energy from IS to begin

Question 15

What four classifcations of fire cause?

Answer 15

Accidental
Natural
Incendiary
Undetermined

Question 16

What types of patterns develop in excitement/vanity arson?

Answer 16

Days/dates of week
Time of day
Type of structure
How fire is set
Where fire is set

Question 17

Most small children under the age of _____ experiment with fire out of curiosity.

Answer 17

7

Question 18

The majority of fires set as a result of psychosocial conflicts (revenge, anger, attention) is during what ages of children?

Answer 18

8 to 13

Question 19

Junior firesetters between 15 and 18 y/o are considered:

Answer 19

the crisis phase, have long history, end in arrest detention