By: Don Penven
Luminol is a chemiluminescent substance that is used as a presumptive test for the presence of blood. Making use of the peroxidase-like activity of the heme portion of hemoglobin, Luminol produces a bluish-white light that can be viewed in total darkness. Invisible blood stains react with the Luminol reagent by luminescing—but darkness is essential. Luminol is a useful test for searching large areas for blood, especially if the area has been cleaned up. Sensitivity:1:100,000.
Luminol is available in several different packages and quantities. It is supplied as a pre-measured dry powder along with a specific amount of distilled water. Once mixed, Luminol has a relatively short shelf life.
The advantages of using Luminol for locating minute traces of blood are numerous: it is non-destructive to subsequent DNA profiling; it is a relatively safe compound if used according to directions; and it is simple to mix and apply.
Preparations for use:
Note: Since the luminescence fades rather quickly, have a tripod-mounted camera ready to use as soon as luminescence appears.
Warning! Luminol, in its solid or mixed state, is hazardous and should be mixed in a well-ventilated area or laboratory hood. Severe skin, eye and respiratory irritant—wear protective clothing, gloves and safety glasses/goggles.
1. Remove cap from bottle of “B” solution.
2. Remove clip and pour entire contents of pouch “A” powder into bottle of “B” solution.
3. Recap bottle with supplied spray head attachment and shake well until all solid material dissolves.
4. Luminol is ready to be applied to suspect areas. Set the spray nozzle to “MIST.”
Instructions for use:
1. Photograph the scene prior to processing with Luminol.
2. Turn off all lights and darken the area as much as possible—luminescence may be very weak and is best seen in total darkness. Note: A night vision flashlight (red beam) such as LVL100 LumaVision™ may be used to illuminate the area while processing the scene.
3. Process small 2-3 sq. ft. areas at a time. When luminescence is revealed, prepare to take photos (absolutely no flash is to be used). Notes: Photo Evidence Markers such as PEN15 can be used to indicate the locations of luminescence so they can later be photographed under full light or with a flash.
4. Reapply Luminol as necessary if luminescence fades too quickly before photos can be taken.
Carpet suspected of holding blood prints
Luminol developed footprint
For complete instructions, you may download the Technical Information Bulletin on Luminol
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