What is the right order for fresh and dried urine?
The CRI's Spot Solver has two entries, one for wet urine and one for dry urine, and the order differs. Use each solution only while it is still lifting colour onto the cloth, then move to the next. The ammonia row is the CRI's; for a pet accident, the ASPCA says to leave it out (see below), so this table marks where the enzymatic cleaner goes instead.
| Step | Fresh (wet) urine | Dried urine |
|---|---|---|
| First | Blot until nearly dry, then detergent solution | Detergent solution |
| Second | Vinegar solution | Warm water |
| Third | Warm water | Vinegar solution |
| Fourth | CRI: ammonia solution. For pets: an enzymatic pet-odour cleaner instead | CRI: ammonia solution. For pets: an enzymatic pet-odour cleaner instead |
| Last | Call a professional | Call a professional |
How strong should each solution be?
Weaker than most people make it. The CRI's own mixes are:
- Detergent solution: one quarter teaspoon of liquid dish detergent per cup of lukewarm water. The CRI's words: "NEVER USE A STRONGER CONCENTRATION!" Never laundry detergent or dishwasher detergent.
- Vinegar solution: one cup of white vinegar per two cups of water.
The CRI also lists an ammonia solution (one tablespoon of household ammonia per cup of water) and warns it "can cause a color change". On a pet accident, leave it out, for the reason in the next section.
Why skip ammonia on a pet accident?
Because to the animal it smells like urine. The ASPCA's guidance on urine marking says: "Do not clean up accidents with an ammonia-based cleanser. Urine contains ammonia, so cleaning with ammonia can attract your cat that same spot to urinate again." Its advice instead: "Clean accidents thoroughly with an enzymatic cleanser designed to neutralize pet odors." The CRI's list is written for urine in general; the ASPCA's is written for pets, and on a pet accident the pet-specific advice wins. How to use one properly is in do enzyme cleaners work.
Apply each with a white cloth, work from the edge of the spot toward the centre, blot rather than rub, and rinse with plain water before switching to the next solution.
Why not use a steam cleaner on pet urine?
Because heat fixes it. The CRI's care advice for homes with pets says: "Don't use a steam cleaner when dealing with urine spots because the heat will set the stain and the smell. Instead, extract the spill with a wet vacuum and rinse with cool water to reduce the odor." That is why a professional clean treats urine areas on their own first, before the hot rinse of the rest of the room.
Which mixes are dangerous?
Two that turn up in home remedies. Transport Canada's CANUTEC warns that bleach mixed with ammonia-based cleaners "creates chloramine vapours, which are harmful when inhaled", and that urea, which is in urine, reacts with bleach the same way. It also warns against mixing hydrogen peroxide and vinegar, which forms peracetic acid. So no bleach on urine at all, and use the solutions one at a time, rinsing between them, never mixed in one bottle. If a pet keeps going back to the same place, see why a pet keeps using the same spot.
Why does the smell come back after the spot is gone?
Because the urine went further than the carpet. A dog or cat accident that was not caught soaks through the carpet into the pad and sometimes the subfloor, and what stays there gives off odour again whenever it takes on moisture, which is why it is worse on humid days. Surface cleaning cannot reach it. The pet urine and odour page explains how to tell a surface spot from a pad problem.
When is it time for a professional?
When the spot is old, large, or has been used more than once, and when the smell outlasts the stain. The CRI's own advice is to call in a carpet cleaning firm "that knows how to remove pet stains and odors permanently" when home treatment is not enough. Tell the cleaner where every pet area is when you book, so they are treated before the main clean. Homes with pets also belong at the short end of the cleaning schedule; see how often to clean carpets.
Get a free carpet cleaning quote
Tell us which rooms, how many stairs, and about any pets or stains. We reply within one business day, by phone or email, and the quote is agreed before anyone starts.