Police Department Fingerprint Lab

 

When working in a laboratory setting, detectives dust for prints under an exhaust hood. Fingerprint powder is extremely messy, like charcoal.

Detectives use light, brushing and swirling motions to apply print powders.

Fingerprinting material – powders, tape, and brushes. Brushes are stored in narrow, plastic tubes seen in the lower right-hand corner of the cabinet above. This helps retain the shape of the brush.

Detectives place the handle of the brush inside the tube first, then give the end of the tube a slight tap on a flat surface, such as a tabletop. The entire brush then gently slides all the way into the tube in a single motion. A trick-of-the-trade.

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CynoVac fuming chamber for glue-fuming prints on large, bulky items. Glue-fumed prints develop best inside a vacuum. This device is designed to create a controlled vacuum which also prevents over-fuming. Price tag – $1,000.00

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The long, black, tube-like device on the countertop above is another CynoVac Fuming Chamber.  It’s designed for glue-fuming prints on long, narrow items, such as rifles and shotguns. Price tag – $1100.00. A CynoSafe is pictured on the left side of the countertop.

Some of the types of fingerprint powders other than the standard black or white (there are many more):

Chrystal violet – enhances sweat residue

Iodine chrystals – for developing prints on porous material, such as paper

Rhodamine 6g – enhances cyanocrylate-develpoed prints

Fluorescent powder – for multicolored backgrounds.

*As a rule, black powder is normally used on light colored surfaces and white is used for dark ones.

* By the way, I’m guest blogging today over at Suspense Novelist. Stop by if you get a chance. My topic is Writing About Cops – It’s Not That Difficult.

http://suspensenovelist.blogspot.com/

Never correct or rewrite until the whole thing is down. Rewrite in process is usually found to be an excuse for not going on. ~John Steinbeck