Bloodstain Pattern Analysis Terms

Accompanying Drop

A small blood drop produces as a by-product of drop formation.

Altered Bloodstain

A bloodstain or pattern with characteristics that indicate a physical change has occurred. (i.e skeletonized stains, blood into blood, dried stains, wipes, swipes, etc.).

Angle of Impact

The acute angle at which a blood drop strikes a target; relative to the plane of the target.

Area of Convergence

The are of intersection in two-dimensions created by lines drawn through the long axis of individual stains; most often associated with an impact pattern.

Area of Origin

The are in the three-dimensions of a blood source most often associated with an impact pattern.

Back Spatter Pattern

A bloodstain pattern resulting from blood drops that travel in the opposite direction of the external force applied; often associated with entrance wound of a gunshot.

Blood Clot

A gelatinous mass formed as a complex mechanism involving red cells, fibrinogen, platelets, and other clotting factors.

Bloodstain

A spot or stain made by blood.

Bloodstain Pattern

A characteristic grouping or distribution of bloodstains which may indicate the manner in which the pattern was deposited.

Bubble Ring

A ring in a bloodstain that results from air bubble.

Cast-Off Pattern

A bloodstain pattern resulting from blood drops released from a bloodied object in motion.

Cessation Cast-Off Pattern

A bloodstain pattern resulting from blood drops released from a bloody object as it suddenly stops (rapid deceleration)

Directionality

The path of travel of a blood drop indicated by the stain’s shape.

Directional Angle

The angle between the long axis of a bloodstain and a reference line on the target.

Drip Pattern

A bloodstain pattern resulting from liquid dripping into liquid, where at lease one liquid is blood.

Drip Stain:

A bloodstain resulting from the formation and falling of a drop of blood.

Drip Trail

A series of bloodstain that result from blood dripping from a source that is in horizontal motion.

Edge Characteristics

The physical characteristics at the periphery of a bloodstain that may be described as spines, scalloping, smooth, or irregular margins.

Expiration Pattern

A bloodstain pattern resulting from blood being forced out of the nose, mouth or a wound by air pressure.

Flow Pattern

A bloodstain pattern resulting from the movement of a volume of blood on a surface due to gravity and/or movement of the target.

Forward Spatter Pattern

A bloodstain pattern resulting from blood drops that travel in the same direction as the external force applied; often associated with the exit wound of a gunshot.

Impact Pattern

A bloodstain pattern resulting from an object striking liquid blood.

Insect Stain

Bloodstains produced as the result of insect activity.

Mist Pattern

A bloodstain pattern resulting from blood reduced to a spray of localized micro drops as a result of the force applied, often associated with gunshot injuries.

Parent Stain

The bloodstain from which cast-off or satellite bloodstain originate.

Pool

An accumulation of liquid blood on a surface.

Projected Pattern

A bloodstain pattern resulting from the ejection of volume of blood under pressure, often associated with vascular breach (arterial gushing/spurts)

Satellite Stain

Smaller bloodstains that originate during the formation of the parent stain as a result of blood impacting a surface.

Saturation Pattern

A bloodstain resulting from the accumulation of liquid blood in an absorbent material.

Serum Stain

The stain resulting from the liquid portion of the blood that separates after coagulation.

Skeletonized Stain

A bloodstain which has been altered after a period of drying leaving observable peripheral characteristics of the original stain.

Spatter Stains

Bloodstains resulting from blood drops distributed through the air due to an external force applied to a source of liquid blood.

Splash Pattern

A bloodstain pattern resulting from a volume of liquid blood that falls or spills onto a surface.

Swipe pattern

A bloodstain pattern resulting from the transfer of blood from a bloodied surface onto another surface, with characteristics that indicate relative motion between the two surfaces.

Target

A surface onto which blood has been deposited.

Transfer Pattern/Stain

A bloodstain pattern resulting from contact between a wet bloody surface and another surface.

Void

The absence of blood in an otherwise continuous bloodstain pattern.

Wave Cast-Off Stain

A satellite bloodstain that originated from a parent bloodstain due to the wave-like action of the liquid that occurs when the parent drop strikes a surface at an angle.

Wipe Pattern

A bloodstain pattern resulting from an object moving though a pre-existing bloodstain altering the original stain.

Ghosting

Not an official SWIGStain term but something you may run into when dealing with a scene containing a large quantity of blood.