LOCATE PET URINE SOURCES...
The amber-colored pet urine is composed of protein metabolism waste products, with feline diets typically protein richer than dogs. The urine will glow in the dark using a blacklight (longwave UV light). Since the UV light is relatively weak, it works best to darken the room as much as possible.
Using lower wattage blacklights (4 watt) require being close to the inspection area with it as dark as possible.
Forgeries of bank notes, standard checks and travellers' checks are mainly printed on inferior bleached paper or photocopied. Forgeries will glow under UV light and bona fides will be completely dull. Many newer credit cards have an invisible imprint on the front. American Express uses "AMEX". If no imprint, the card is a forgery. Alterations of legal documents such as careful erasure or ink eradication and altering paper textures are detectable with UV light.
Authentic U.S. paper currency has embedded stripes which will fluoresce under ultraviolet light as follows: $5 glows blue, $10 glows orange, $20 glows green, $50 glows yellow, and $100 glows red. The $1.00 bill has no stripe.
GEMSTONE and MINERAL INSPECTION
UV Light can react with the chemicals of a mineral specimen and cause it to glow, called fluorescence. Color and intensity of the fluorescence can identifty many materials. Some minerals and gemstones will fluoresce under shortwave UV ligh and not fluoresce under longwave.
In arson detection, accelerants' fluorescent glow is greater when exposed longer to heat. Their evidence is not always visible as they are absorbed by the fire but UV light can expose them.
Volatile hydrocarbons such as gasoline, grease, paints and others fluoresce when exposed to UV, and can be seen as fragments of incendiary devices. Ambient light must be minimized for use of UV light at a fire scene.
CRIME SCENE INSPECTION
Illegal dumping can be tracked at night using UV light.
UV light is used to detect the presence of trace evidence in forensic investigations. Blood, urine, semen and saliva can present visible fluorescence.
UV or black light reveals changes on the surface of objects as it causes specific fluorescence in materials depending on composition and age. UV fluorescence can show overpainting or retouching and identify types of stains.
One can detect repair in paintings and rugs using UV light, as differences can be seen between the chemical composition of newer inks, paints, and dyes and that of the originals.
ADMISSION / ACCESS OR CROWD CONTROL
In high-patronage clubs, amusement parks and swimming pools, applying quick drying readmission inks can be read easily by UV light. For beverage control, a portable, small UV light can slip in a pocket.