Yes, for dried pee. Smell it but can't find it? In a dark room, a UV flashlight makes dried dog pee glow, so you can find spots your nose missed and see how far each one spread. Mark every glow with painter's tape, treat each spot with enzyme cleaner, then sweep again once it is dry.
What the glow can and can't tell you
- What else glows. Preventive Vet lists laundry detergent, milk, honey, tonic water and antifreeze among the things that glow too, and Legend Brands, a cleaner maker, says a spot you already cleaned can still glow. A glow shows where to look, not what it is, so smell-check each spot.
- Fresh spots. Reader's Digest says the light shows only dry urine, so let a fresh spot dry before you sweep.
- How dry the spot is. Dried urine often shows up, so treat the whole glowing patch, not just the middle.
- Where it landed. Check the places you would never think to sniff: splatter, baseboards, furniture legs and the lower part of a wall. The sweep shows them.
- How deep it went. What you see on the surface is usually smaller than what is underneath. If it still smells after a second round, the urine has probably reached the pad or the subfloor.
