To neutralize the smell of cat urine, use a combination of vinegar, baking soda and commercial cleaning products. Use paper towels that can be disposed of afterward. Sprinkle baking soda on all cat urine spots, whether they are wet or dry. It soaks into the carpet fibers and helps remove the smell while also helping to lift the stain.
Avoid using cleaning chemicals that contain ammonia. It counteracts with the urine and causes the smell to worsen. For cleaning cat urine stains, baking soda and vinegar is best. Vinegar is a natural cleaning solution with a potent smell that helps neutralize the smell of urine. After sprinkling the powder on the stain, spray some vinegar on top. Let it sit for a few minutes, then use a wet rag to blot at the stain. Don't rub it, or the stain will get deeper into the carpet fibers.
Another option is to use commercial cleaning products that are meant for pet stains. Be sure it is labeled for cat urine to ensure it contains good ingredients for neutralizing the odor. It is a good idea to test a small area of the floor first to be sure it is safe to use. After the stain is cleaned as much as possible, go over it again with baking soda and vacuum the floors.