Urine-Off, from Bio-Pro Research LLC, permanently purges urine odors and stains from hospitals, convalescent homes, veterinary clinics, bus stations, dormitories, hotels and other settings, even if the problem is as old as the building. The secret is in Urine-Off's approach to removing the non-soluble salt crystals contained in the uric acid that produces urine's pungent aroma. Other products typically clean the urea (the sticky substance in urine) and urochrome (which makes urine yellow) with detergents and masking agents, but leave the uric acid crystals firmly bonded to the surface of the stained area. Every time water, humidity or more urine reactivates the remaining crystals, the odor returns. Urine-Off uses a combination of specially developed enzymes to completely remediate the acid crystals, as well as remove the urea and urochrome. The formula attacks only the offending substances and leaves a pleasant citrus fragrance without harming the fabric, floor covering or other hard or soft surface. It is non-toxic, non-pathogenic and biodegradable for safe use in any environment. Bio-Pro Research LLC.