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Thursday, October 08, 2015


We are about to start using a black light to check carpeting for pet stains when apartment residents move out. Will the black light only show urine on the fibers, or will it also be apparent on the backing and pad?


A black light illuminates phosphors, especially uric salts. There are other products containing zinc or fluorescent dyes that will also fluoresce, but the distinct pattern animals leave are a give away regarding pet urine. Pet urine is fluoresced as bright yellow spots, streaks and drips. It will show damage on the backing and pad. A black light will not detect surface urine after the carpet has been thoroughly cleaned.
The human nose can be trained to determine the degree of urine in a carpet. For example, if you detect a mild urine scent, run the black light exam and treat the contaminated areas with Urine Remover or Enzyme prior to (and
often after) cleaning. If you detect a strong urine odor, most of the contamination will be in the pad.
Disengaging the carpet and inspecting the back, pad and floor will reveal urine damage. At this point, you can determine if treatment or replacement is the most practical. Be sure to black light the walls for urine spray.
Remember; the room must be as dark as possible. Often you will need to place additional blankets over the drapes or perform the exam at night.
Digital photos showing each step of the inspection process should be admissible in court. Urine stains on the carpet backing, pad and floor will show up without a black light.
Gary Clipperton
National Pro Clean Corp
P-719- 598-5112