BPA Definitions

Question 1

Accompanying Drop

Answer 1

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

Question 2

Altered Stain

Answer 2

A bloodstain with characteristics that indicate a physical change has occurred.

Question 3

Angle of Impact

Answer 3

The angle (alpha), relative to the plane of a target, at which a blood drop strikes the target.

Question 4

Angle of Convergance

Answer 4

The space in two dimensions to which the directionalities of spatter stains can be retraced to determine the location of the spatter producing event.

Question 5

Area of Origin

Answer 5

The space in three dimensions to which the trajectories of spatter can be utilized to determine the location of the spatter producing event.

Question 6

Backspatter Pattern

Answer 6

A bloodstain pattern resulting from blood drops which can be produced when a projectile creates an entrance wound.

Question 7

Blood Clot

Answer 7

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

Question 8

Bloodstain

Answer 8

A deposit of blood on a surface

Question 9

Bloodstain Pattern

Answer 9

A grouping or distribution of bloodstains that indicates through regular or repetitive form, order, or arrangement the manner in which the pattern was deposited.

Question 10

Bubble Ring

Answer 10

An outline within a bloodstain resulting from air in the blood.

Question 11

Cast-off Pattern

Answer 11

Bloodstain patter resulting from blood drops released from an object due to its motion.

Question 12

Cessation Pattern

Answer 12

Bloodstain resulting from blood drops released from an object due to its abrupt deceleration.

Question 13

Directionatlity

Answer 13

Characteristic of a bloodstain that indicates the direction blood was moving at the time of deposition.

Question 14

Directional Angle

Answer 14

The angle (gamma) between the long axis of a spatter stain and a defined reference line on the target.

Question 15

Drip pattern

Answer 15

Bloodstain pattern resulting from a liquid that dripped into another liquid, at least one of which was blood.

Question 16

Drip stain

Answer 16

Bloodstain resulting form a falling drop that formed due to gravity.

Question 17

Drip trail

Answer 17

Bloodstain patter resulting from the movement of a source of drip stains between two points.

Question 18

Edge characteristic

Answer 18

Physical feature of the periphery of a bloodstain.

Question 19

Expiration pattern

Answer 19

Bloodstain pattern resulting from blood forced by airflow out of the nose, mouth, or a wound.

Question 20

Flow

Answer 20

Bloodstain resulting form the movement of a volume of blood on a surface due to gravity or movement of the target.

Question 21

Forward spatter pattern

Answer 21

Bloodstain pattern resulting from blood drops which can be produced when a projectile creates an exit wound.

Question 22

Impact pattern

Answer 22

Bloodstain pattern resulting from an object striking liquid blood.

Question 23

Insect stain

Answer 23

Bloodstain resulting from insect activity.

Question 24

Parent stain

Answer 24

Bloodstain from which a satellite stain(s) originated.

Question 25

Perimeter stain

Answer 25

Altered stain consisting of its edge characteristics, the central area having been partially or entirely removed.

Question 26

Pool

Answer 26

Bloodstain resulting from an accumulation of liquid blood on a surface.

Question 27

Projected pattern

Answer 27

Bloodstain pattern resulting from the ejection of blood under hydraulic pressure, typically from a breach in the circulatory system.

Question 28

Satellite stain

Answer 28

Smaller bloodstain that originated during the formation of the parent stain as a result of blood impacting a surface.

Question 29

Saturation stain

Answer 29

Bloodstain resulting from the accumulation of liquid blood in a n absorbent material.

Question 30

Serum stain

Answer 30

The stain resulting from the liquid portion of blood (serum) that separates during coagulation.

Question 31

Spatter stain

Answer 31

Bloodstain resulting from an airborne blood drop created when external force is applied to liquid blod.

Question 32

Splash pattern

Answer 32

Bloodstain pattern created from a large volume of liquid blood falling onto a surface

Question 33

Swipe

Answer 33

Bloodstain resulting from the transfer of blood from a blood-bearing surface onto another surface, with characteristics that indicate relative motion between the two surfaces.

Question 34

Target

Answer 34

A surface onto which blood has been deposited.

Question 35

Transfer stain

Answer 35

Bloodstain resulting from contact between a blood-bearing surface and another surface.

Question 36

Void

Answer 36

An absence of blood in an otherwise continuous bloodstain or bloodstain pattern.

Question 37

Wipe

Answer 37

An altered stain resulting from an object moving through a pre-existing wet bloodstain.

Question 38

Formula for determining area of origin

Answer 38

(W/L) Sine-1 = (Impact Angle) x Tan = (X) x Dist from area of convergence to leading edge of bloodstain = Area of Origin

Question 39

Formula for determining angle of impact

Answer 39

(W/L) Sine-1 = Angle of Impact