bloodstain patterns

What is the effect of surface texture on blood spatter results?

The harder and less porous the surface, the less spatter results; rough surfaces usually create irregular shapes with possible satellite spatter.

Define spatter in bloodstain pattern analysis.

Spatter refers to small circular or elliptical shaped stains.

How does directionality relate to blood droplets?

Directionality defines the direction a droplet was moving at the time it struck a surface, with the tail pointing in the direction of travel.

What is impact spatter?

Impact spatter occurs when an object impacts a source of blood, leading to small circular or elliptical stains.

What is the size range for low velocity spatter?

Low velocity spatter consists of drops with diameters of 4 mm or more.

What categorizes medium velocity spatter?

Medium velocity spatter consists of drops with diameters from 1-4 mm, typically resulting from forces of 5-25 ft/sec, often associated with blunt force trauma.

Describe high velocity spatter.

High velocity spatter consists of drops that have a diameter of less than 1 mm, resulting from an applied force of 100 ft/sec or faster, such as gunshot wounds or explosions.

What is gunshot spatter?

Gunshot spatter includes fine forward spatter from an exit wound and back spatter from an entrance wound.

What creates cast-off spatter?

Cast-off spatter is created when a blood-covered object flings blood in an arc onto a nearby surface.

Define arterial spray spatter.

Arterial spray spatter is caused by an injury to the heart or a main artery, characterized by the pressure of the continuing pumping.

What are expectorate blood patterns?

Expectorate blood patterns show the presence of bubbles of oxygen in drying drops or lighter color due to dilution by saliva, indicating blood in an airway.

What are wipes and swipes in bloodstain pattern analysis?

A swipe is a pattern caused by a bloodstained object contacting a non-bloodstained object laterally; a wipe is caused by an object contacting pre-existing bloodstains laterally.

What is a drop trail pattern?

A drop trail pattern is a series of drops that are separate from other patterns, formed by blood dripping off an object or injury.

How can UV light assist in bloodstain pattern analysis?

Luminol can be sprayed to detect bloodstain patterns that are not visible, shining blue to reveal cleaned-up blood.

What is the void pattern in bloodstain analysis?

A void pattern is created when an object blocks the deposition of blood spatter onto a target surface or object.

What documentation methods are commonly used for bloodstain evidence?

The grid method and perimeter ruler method are used for documenting bloodstain evidence.

What factors influence blood pool shapes in bloodstain patterns?

Blood pools conform to the surface they are on and do not have a specific shape.