While there are many methods for removing dog urine odor from particleboard subfloors—including sanding, covering the stain with Kilz sealer or using vinegar—these methods don't always work well. Sanding sometimes isn't enough to completely remove the stain. With Kilz, odor can return if the floor gets moist. And vinegar won't clean the floor completely. Flooring installers generally agree that one product works best: Urine Off. Here's how to use the product to best effect.
Things You'll Need
Broom and dustpan
Sweep the floor. Do not use a vacuum, which can make your vacuum smell like urine forevermore.
Shine a black light on the particle board floor. Anything that glows yellow is old urine.
Squirt the Urine Off onto the urine areas. The odor will begin to smell worse, and the stain will get darker, but that's OK. This means the product is breaking up the urine. Let it dry.
Examine the stain again with the black light. It should be smaller.
Repeat these steps until the stain goes away completely.
If you're not sure what urine looks like under a black light, take the black light into the bathroom and look around the toilet. You'll see the crystals immediately.
Urine Off recommends that you do not use any other cleaners first, as the urine may be further set in.