Yes, you read that correctly. A while back I purchased a blacklight flashlight to find dried dog urine in our house. Why? Because when you have two young puppies it’s not uncommon to identify the smell of urine but to not be able to find the source…

They’ve grown a good bit since I originally purchased it and it’s less of an issue now. That’s not to imply that they don’t “go” in the house anymore but it’s not as frequent and also less likely that we won’t notice.

There was a time, however, when they would frequently sneak off and piss in a corner or under a table and we wouldn’t notice it for a while. On wooden floors can be difficulty to see after it has dried.

Does this work? The short is answer is that yes, it does.

But it’s not a perfect system and if you expect to see bright markings glowing like some kind of crime scene then you will be disappointed. The urine doesn’t glow very brightly but it should be just enough to be able to spot it on an otherwise clean floor.

Typically, urine that is still wet does not fluoresce though I see that as being less of a problem since it’s easier to spot.

This is useful in some cases but it is worth mentioning that you really do need to turn off all lights and do the inspection at night. Even a little bit of light can make this less useful.

It also has a second use. Pet toys often fluoresce brightly due to the materials that they are made from. If you’re planning to mow some tall grass one day then it might work well to go out into the yard with one of these lights to find toys that may be difficult to see, even in the daytime.