FP Development Pwdrs Flashcards
What is the employer responsible for regarding health and safety?
Employer must supply adequate training and protective equipment.
What is the employee responsible for with regards to health and safety?
Know the materials used (read the SDS)
Use protective equipment
What is the PPE for FP powders?
Dust mask
Protective clothing - lab coat
Latex/nitrile gloves
Eye protection when using UV light or forensic light source
What letter is used to mark fingerprint impressions?
What letter is used to mark footwear impressions?
R
F
What are the steps to follow when developing impressions?
1- develop the latent
2- mark notations on scale (data tab)
3- apply scale beside FP - ensure measurement markings are against FP
4- Apply R or F, date, initials, file number with dry erase or grease pencil
5- circle the FP, cluster, palmprint, or footwear impression and marking
6- powder over markings
What are the three types of impressions?
Latent
Visible (blood, dust, paint, etc)
Molded (plastic) (clay, cheese, chocolate, paint, blood)
How do you search for a latent impression?
Use a light source and/or contrasting background
What are the lighting sources/techniques to search for impressions?
Oblique
Graze
Back lighting
Fluorescence
Colour filters
What MUST you do with visible and molded impressions before trying any enhancements?
Photograph
What factors to consider to determine whether and which powder to use
1- presence of foreign material
2- type of substrate
3- probable age of print (cannot be determined by its appearance)
4- monetary or sentimental value
5- portability
What factors affect the longevity of FP?
1- atmospheric conditions
2- substrate
3- composition of matrix (sweat, oil, blood)
4- amount of matrix
5- contamination
What is the purpose of powders?
1- to make the latent impressions visible
2- to create contrast with the background
3- to enable the impressions to be photographed
4- to potentially enable the impressions to be lifted
What are types of development powders?
Regular
Fluorescent
Magnetic (regular & fluorescent)
What are the three regular powders we will use?
Black: avail in course or fine, best for lifting
Silver/lighting gray: finest and most sensitive powder, cautious application
Grey/chemist gray: course, can be applied over silver, more forgiving
What are some characteristics of fluorescent powders?
Most volatile and hazardous to health
Applied in darkness under UV
