Fire Origin and Cause Determination

Question 1

True or false, it is only the responsibility of the fire investigator to recognize the fire’s area of origin.

Answer 1

False, it is the job of every firefighter to recognize and protect the area of origin.

Question 2

In most jurisdictions, whose responsibility is it to determine the cause of the fire?

Answer 2

The fire chief’s.

Question 3

True or false, the fire chief must attend every fire to determine the fire cause.

Answer 3

False, the fire chief can delegate the authority of the investigation to a qualified fire officer or firefighter on scene.

Question 4

If you are the first firefighters on the scene, what five things should you make a mental note about?

Answer 4

• Vehicles and people present at the scene.
• Whether doors and windows were open of closed
• Evidence of forced entry other than that of a firefighter
• Condition of the contents inside, if it looks normal, ransaked or too empty.
• Unsusual fire behaviour

Question 5

True or false, it is encouraged to discuss the potential cause of the fire with other firefighters at the scene so that everyone can get fire investigation experience.

Answer 5

False, you should avoid talking about the cause incase anyone hears you and reports it in the news as a fact.

Question 6

What is the only thing that you ought to say to a reporter regarding the cause of the fire?

Answer 6

“The fire is under investigation.”

Question 7

True or false, an insurance investigator is allowed to condict heir investigation at the same time as the fire department fire investigator.

Answer 7

True

Question 8

Where is the best place to look for the fire cause?

Answer 8

The area of origin

Question 9

What is the best way to find the area of origin?

Answer 9

It is usually the place with the most fire damage

Question 10

When looking for the area of origin, where is the best place to start your search?

Answer 10

Start at the unburned side of the house or at the outside if the whole structures is burned. Look for fire patterns to determine the area of origin.

Question 11

What are the five interior fire patterns?

Answer 11

• V-shaped
• U-shaped
• Hourglass
• Circular shaped
• Inverted cone

Question 12

What evidence of fire cause can be made from the outside of the structure?

Answer 12

• Building damage
• Ventilation patterns
• Means or ingress and egress
• Utilities
• Tire tracks or footprints
• Fuel cans
• Forcible entry
• Surveillance cameras at or around the scene

Question 13

Which comes first; the interior or exterior examination?

Answer 13

Exterior

Question 14

Which is usually more damaged in a structure fire; the floor or the ceiling?

Answer 14

ceiling

Question 15

Lets say that you are in a hallway and to your left the charring is a darker black and to your right the charring becomes gradually less dark. Which direction is the area of origin likely to be?

Answer 15

To your left

Question 16

True or false, multiple areas of intense burning means tha the fire was an arson.

Answer 16

False, it could also be an accidental fire that had some objects that burned intensely.

Question 17

What six factors can affect the fire spread and should be evaluated by the fire investigator?

Answer 17

• Material and composition of objects in the house
• Building features that contribut or resist fire spread
• Ventilation openings
• Combustible materials present
• Fire suppression tactics
• Activation of fire suppression systems

Question 18

True or false, burned long grass will fall towards the area of origin.

Answer 18

True

Question 19

How should you approach a vehicle fire that you are trying to investigate, even if it is extinguished?

Answer 19

Use the same precautions as discussed in chapter 17

Question 20

What is the competent ignition source?

Answer 20

The nheat source that ignited the fire.

Question 21

What is an ignition sequence?

Answer 21

The ignition source and the material that first ignited. The history of the fire.

Question 22

What three qualities must a competent ignition source have?

Answer 22

• Sufficient temperature
• Sufficient heat energy transfer to result in ignition
• Sufficient time to transfer the required amount of energy

Question 23

Which are the easiest to ignite; gases, liquids or solids?

Answer 23

Gases, then liquids, then solids

Question 24

What three qualities must the material first ignited have to be determined to be the material first ignited?

Answer 24

• Capable of being ingnited by the energy output of the identified ignition source
• Close enough to the ignition source to receive the energy from the ignition source
• Capable of absorbing sufficient energy to begin ignition

Question 25

Why is surface to mass ratio important in determining the first fuel ignited?

Answer 25

Large pieces of fuel are very difficult to make catch fire, so the first fuel ignited must be someting small or easily ignited like liquid or gas.

Question 26

Why is fuel orientation important in determining the first fuel ignited ?

Answer 26

Because if a piece of paper is vertical, it will burn faster and with more heat than if it were placed horizontally due to convective heat.

Question 27

True or false, failure to act in order to prevent the ignition of a fire is still a contributor to ignition.

Answer 27

True it is called omission

Question 28

What are the four types of fire causes?

Answer 28

• Accidental
• Incendiary
• Natural
• Undetermined

Question 29

If a buuilding is completely destroyed in a fire and no cause can be found, what classification does it fall under?

Answer 29

Undetermined

Question 30

If a hay bail decomposes and auto ignites is that a kind of ommission or is it natural causes?

Answer 30

Natural cause

Question 31

Do the accounts of eye witnesses count as evidence?

Answer 31

Yes

Question 32

What is direct evidence?

Answer 32

Evidence gathered using the senses at the time of fire ignition. Ex: watching someone lighting a car on fire, smelling gasoline being thrown on a fire instead of water. smelling propane in the air before a fire ignites.

Question 33

True or false, Circumstantial evidence are facts that support an argument. like if someone is seen with a propane torch and then is seen running from an ignited building later.

Answer 33

True, it is not evidence that can convict someone automatically, but it can support an argument.

Question 34

What kind of evidence do fire investigators most heavily rely on during investigations?

Answer 34

Circumstatial as they rarely see the fire themselves.

Question 35

What is physical evidence?

Answer 35

Evidence that does not require a witness. if there is evidence of a forcible entry, it is likely that the fire waas caused by arson.

Question 36

What is spoliation?

Answer 36

Evidence that is destroyed or ruined by someone that is responsible for its preservation.