DISCLAIMER: Although Fluorescein has been used as a presumptive blood test to help detect trace amounts of blood, a positive reaction may also indicate the presence of cleaning products, urine, metals, and/or strong oxidizers. 

1. Prepare by darkening the room where the item or surface is located, setup photography equipment with proper barrier filters, and mix working solutions as directed. 

2. Apply Fluorescein to the item or surface. 

Spray application: Lightly spray area with premixed solution (finer is mist preferred). 

3. Apply 3% hydrogen peroxide solution or overspray solution to the item or surface.

Spray application: Lightly spray area with hydrogen peroxide solution (finer mist is preferred). 

4. The fluorescing reaction only lasts 5 – 7 minutes, and therefore must be photographically documented quickly.

5. Although reaction times may be shortened and the suspected blood may become diluted, the Fluorescein and hydrogen peroxide solution may be reapplied after allowing the surface or item to air dry.

6. Positive reactions will develop a bright yellow color and can be captured using low-light photography.

7. View the fluorescent area for ridge detail using a forensic light source in the 415 – 480nm range with yellow or orange goggles.

8. Capture ridge detail (if applicable) using 1:1 photography and a deep yellow or orange barrier filter.