What is a black light used for?

According to Glo Bright, a black light is generally used to illuminate bedroom posters or glowing paint used in places like bowling alleys, haunted houses, amusement parks and miniature golf courses. A black light can be used for illuminating crime scenes in search of biological substances like urine and blood.

Black lights that are used for the purpose of visual effects are called long wave lights, as they emit light that is associated with a particular light spectrum. Black lights used in household environments are used to fluoresce objects, and this includes law enforcement's use of identification of biological waste.