We have discussed using the eyes and nose to locate the source of your urine odor in part one. In part two we will discuss using ultraviolet light and the use of a moisture sensor.
ULTRAVIOLET LIGHT (black light) to locate urine odor. Urine residue will glow under a black light. Ultraviolet lights in several intensities are available to help you locate urine deposits. Low powered black lights must be held very close to the carpet in a dark room. Medium intensity lights will work from a few feet away. High powered lights can quickly be used to check a carpet and other fabrics from several feet away. All black lights work best in a dark room but this is not as critical when using a more powerful light. When necessary, black plastic sheeting can be used to cover windows and light sources. Another option is to drape a sheet or dark blanket over yourself while you are making the inspection. Black lights are readily available at many price points.
You will recognize urine by the shape of the spot and by its characteristic yellow (from dogs) glow. However, a bluish glow may indicate urine stains where cleaning has been previously attempted with a product that contained an optical brightener.
MOISTURE DETECTOR to locate urine odor. Use a moisture probe to examine all the carpet in question. As urine dries a chemical reaction creates an alkaline salt. Alkaline salts are hygroscopic, that is they absorb moisture from the air. In all but the driest conditions the salt residue will hold enough moisture to activate a moisture probe. Moisture detectors are harder to find and can get expensive.
Use all the tools you can– eyes, nose, moisture detector and UV light -to locate all urine deposits. Be sure to mark the location of all odor areas. Use white chalk, pennies or some other markers. A diagram on graph paper will help you locate the problem areas if the treatment is being done at a later time.
See also part one “urine odor, locate the source”