Fire

Fire needs what % of oxygen

16

Air is what % of oxygen

21

Substances, such as gasoline, paint thinner, and alcohol, that accelerate the burning process

Accelerants

A fire started deliberately

Arson

Noticeable patterns created by the fire as it burns

Burn patterns

Created by very hot fires that burn very quickly and move fast along its path, so that there can be sharp lines between what is burned and what isn't

Char patterns

Since fire burns upwards, the fire ignites at a point, the superheated gases rise upward and form a fireball, which continues straight up to burn a hole in the ceiling.

Chimney effect

Indicates at what temperature the fire was burning.

Color of flame

Determine what type material was burning

Color of smoke

Produced when a substance undergoes rapid oxidation involving heat and light

Fire

Shows the three elements needed to produce and sustain a fire

Fire triangle

The lowest temperature to which a substance must be heated in order for the substance to give off vapors which will burn when exposed to a flame or ignition source

Flash point

any combustible material in any state of matter

Fuel

Three elements in the fire triangle

Fuel oxygen heat

Glass fragments, windows, and light bulbs can provide clues to a fire

Glass

energy necessary to increase the temperature of the fuel to a point where sufficient vapors are given off for ignition to occur

Heat

Occur when heavy furniture shields part of a wall; can help determine the origin point

Heat shadows

Clear glass with an abnormal pattern of cracking could imply

Hot fire possibly due to an accelerant

Narrow v shape patterns indicate

Hot fire/accelerant used

What does a char pattern on the floor help investigators know

If an accelerant was used and its path

Burn patterns and other damage can help determine the point of origin, or the location where the fire started

Point Of origin

The location where the fire started

Point of orgin

U patterns indicate

Point of origin. Where accelerants were pooled

Wide v patterns indictate

Slow burning fire

A dark soot layer on the glass could indicate

Slow smoldering fire

Which way does glass bulbs melt

Towards the fire

Fire burns up, in a V-shaped pattern, so a fire that starts at an outlet against a wall leaves a char pattern that points to the origin

V pattern

A char pattern on a door helps fire detectives know

Which side of the door the fire was on

THe shattering or cracking of glasses windows provide

indications as to how a fire burned