How to Dust for Fingerprints

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Ever wanted to find out who stole the cookie from the cookie jar? Take a page from crime scene investigators and get the proof you need.

Step 1: Fill balloon halfway with water
Fill the balloon halfway with water from the tap. Remove from the faucet and fill the other half with air. Tie it off.

Step 2: Hold balloon over candle
Light a candle. Hold the balloon at the knot end and dangle it above the flame, so the tip of the flame touches it. After 15 to 30 seconds, the smoke from the candle will collect as soot on the balloon's surface.

Step 3: Collect the soot from the balloon
Using the brush, collect some of the carbon soot from the balloon.

Step 4: Brush the soot onto the fingerprint
Brush the area you want to search for fingerprints, coating it lightly with soot. If you need more soot, hold the balloon over the flame again until you get enough soot to dust with.

Tip
The smoother the surface, the better the fingerprinting results will be.

Step 5: Identify a fingerprint
Look for the patterns and swirls that identify a fingerprint. The oils in the print will make more of the carbon stick than the areas directly around it.

Step 6: Collect the fingerprint
Once you've located a print and it's covered in soot, place a piece of clear tape over it. When you remove the tape, the fingerprint will be stuck to it!

Did You Know?
About 40,000 fingerprints are added to the FBI's database every day.