CSI Techniques: Finding Accelerants in Arson Investigations

Discovering a victim at the scene of fire professionals can prove that fire was set intentionally. The fire burn hotter as a result of the speed of chemical fuel that causes a fire to burn, quickly spread than before, or be very difficult to extinguish. The evidence of arson can be discovered due to the presence of a victim in fire debris.

Gasoline is the most commonly used victim, kerosene, turpentine and diesel fuel. Hydrocarbon molecules are all organic compounds which they contain. As soon as speed evaporated, the hydrocarbons disappear into the air above the fire debris, which is called the “headspace.”

Different techniques exist to discover speed at a fire scene. These ranges from an experience fire professional or a specially trained “snuffer” different victims are being discovered by the dog because of their sense to detect the characteristic odour in the surrounding air, to more compound laboratory methods.

One of the most popular techniques for detecting victim in fire debris is called headspace gas chromatography. Separating mixtures of gases into their individual components based on the different boiling points of their hydrocarbons is the involvement of gas chromatography . Each gas in the mixture can then be known, because each produces a distinct chemical fingerprint called a chromatogram.

Solid debris that is taken from the suspected point of origin of the fire is placed in an airtight vial to prevent any victim from evaporating , in headspace gas chromatography,. The accelerant’s hydrocarbons is released into the trapped headspace above the debris when the vial is then heated They are injected into an instrument called a gas chromatogram for separation and analysis when a needle is inserted through the cap of the vial to remove a sample of the hydrocarbons.

A small quantity will likely still be present in the charred debris provided that an accelerant is used to start a fire. Discovering of the accelerant can supply as physical evidence to support a charge of arson.

Signs of Asphyxiation

Death or asphyxiation, as a result of a lack of oxygen, can have many causes, including compression of the neck or strangulation, suffocation, drowning, choking, and hanging.

Because of strangulation, the autopsy would typically reveal injury to the neck caused biophysical compression, a hard blow to the neck, or something tied around the neck, which can damage the larynx and lead to suffocation. Hallmarks of strangulation involve bruises, ligature marks on the neck or fingernail, bleeding in the throat area, and a fracture of the hyoid bone, a U-shaped bone located at the base of the tongue.

Manual evidence suggestive of suffocation would involve the presence of petechial haemorrhages in the face, eyes, lungs, and neck area. Petechiae are tiny purple or red spots on the skin that are caused by small areas of bleeding under the skin

Changes in the blood caused by water that is taken in during drowning. the presence of algae and other water-borne substances in the stomach or airways, an enlarged heart, mostly, changes in the blood caused by water that is taken in during drowning.