Get Below The Surface To Remove Urine Smell

One of the benefits of a urine stain is that custodial staff knows exactly what it is because of the smell, compared to other stains and spots in which the source is unknown, says Seal.

Once a urine spot is identified, the priority is to get to where the actual urine resides, typically below the surface on subflooring or in a carpet pad.

“You have to remove the source. You have to get to where the bottom of the spot is,” says Yeadon. “If they are trying to take care of a urine problem by sprinkling or spraying something on the top of the carpet, that would be very similar to having a cavity and going to the dentist and them putting a crown on the cavity.”

In places where a carpet is glued down, prohibiting the custodial staff from getting to the pad, subfloor or to the underside of the carpet, the key is full saturation with cleaners that are bio enzymatic (i.e. containing bacteria).

“The enzymes need some time and they need the temperature to be moderate; water can’t be super hot because it will actually kill the bacteria before it does its job,” says Yeadon. “We can’t ever use a disinfecting-type product with it because the disinfectant is going to kill the bacteria. It indiscriminant when it kills.”

Urine tends to spread below the surface of the carpet into an area two to three times the size of spot. As urine dries, it becomes an alkaline, attracting moisture. So, cleaning professionals can use a moisture meter to determine the size of the actual spot.

“The moisture meter is a little stick with two little probes. It will let us know exactly how far the urine has traveled so we know what area to treat,” says Jasper. “When people walk on it, the urine will attract the soil from their shoes…so now you have a spot that is not just urine, but also oil, grease and dirt.”

Some of the hydrogen peroxide products are in powder form that need to be mixed with warm or hot water, says Jasper. The product can then be applied to the spot and typically left for 15 minutes. It then needs to be flushed out with water, which can be accomplished with a sub-surface spot extractor.

“These are tools that can be attached to a hot water extractor or a wet/dry vacuum,” he says. “So you don’t need any fancy or powerful equipment.”

After the spot has been extracted, the carpet will still be wet, so custodians should place a fan or open windows, if possible, near the spot to help dry it. Carpets should be dry within 48 hours to prevent mold and mildew from developing, according to the U.S. Environmental Protection Agency (EPA).