DISCLAIMER: Although Luminol has been used to help detect trace amounts of blood, a positive reaction may also indicate the presence of fibrous foods, paints or varnishes, and some chemical products.

1. Prepare by darkening the room where the item or surface is located, setup photography equipment, and mix a new working solution as directed before each use. 

2. Apply Luminol to the item or surface. 

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

3. The presumptive positive chemiluminescent reaction is indicated by a glowing blue color lasting ~30 seconds, and therefore must be photographically documented quickly.

4. Capture presumptive positive reactions using low-light photography.