Developing Fingerprint Impressions Flashcards
What are the 5 steps to collecting fingerprint impressions?
Develop/locate
Label
Photograph
Document
Preserve
Describe the development/location stage of fingerprint collection.
Powder the surface and circle each impression as you locate it
Describe the labelling stage of fingerprint collection.
Mark each impression with all related information and place scales
Describe the documentation stage of fingerprint collection.
Make notes in memo book including location, R#, diagrams, measurements
Describe the preservation stage of fingerprint collection.
Lift the impression
What are the 5 main techniques of fingerprinting?
Granular powder
Magnetic powder
Metallic powders
Fluorescent powders
Advanced chemical developments
What are the three types of granular powders?
White
Grey/silver
Black
What is the most widely used powder for fingerprinting?
Granular
What are the three benefits of granular powders?
Easily transportable
White/black powders to provide contrast
Works on a variety of non-porous surfaces
What are the two cons to granular powders?
Becomes airborne easily and can be messy to work with
Must be cautious of over-powdering
What type of brush is used with granular powders?
Fibreglass tip brush
What is the most popular type of brush used for fingerprinting?
Fibreglass brush
Why is the fibreglass brush the most common?
Does the least amount of damage to the impression while carrying the most amount of powder
What are fibreglass brushes made of?
Nylon fibres
What is magnetic powder?
Contains iron particles and granular powder
Metal components act as a carrier for the powder
What is a benefit of magnetic powder?
Only the powder touches the surface, no chance of damaging the impression from the brush
Why are granular powders stored in airtight containers?
Granular powders can be contaminated by moisture/foreign material
What are the 5 pieces of information that should be included on a fingerprint label?
GO#
Date
Badge
R# of impression
Location
What is a directionality arrow?
Indicates upwards, used on vertical surfaces only
What is an R#?
Reference number that each lift is assigned
What are the origins of R#s?
Originates from the photographic film and x-ray disciplines
An upper case R cannot be reversed and the orientation is easily established
Describe the 3 steps in photographing fingerprint impressions?
Overall photo
Midrange
Closeup/Macro
