I've know that all the peroxide stain removers (Urine Rescue, Stain Magic, and others) have a limited shelf life. Heat and and light will deactivate them and they are basically worthless. All I've ever heard though is really vague guidlines. "keep only a quart on the truck and change every couple weeks if you don't use it..." "lasts longer in summer than winter..." Is there any way to actually test this stuff to see if its still good or not? I mean besides applying to a stain and waiting 8 hours to see if it disappears...
That is hard to judge. It does not suddenly change from being good to being deactivated. IT is gradually losing strength from the first minutes until several hours later. This may be 2 hours or it may be 12 hours depending upon temperature and other factors. A product may be strong enough to remove some stains even if it is not full strength. You may get out one stain with product that has been mixed up for 3 hours, but another stain may only come out with absolutely fresh product mixed 5 minutes ago. No real test to do in the field other than finding out if the stain is removed. But you won't have to wait 8 hours. You should see signs of progress in 15 minutes or so. There are lab test, but not practical to do on sight. Too many variables to give a specific answer for every product in every situation.
Thanks for your reply. Somehow I missed seeing the response or I'd have replied sooner! I was referring more to the unmixed product than after they've been mixed (the two part products). For example, the straight hydrogen peroxides that haven't been mixed, I've heard they will last anywhere from a couple weeks to a couple months. But I suppose thats all beside the point as the difficulties you pointed out would apply to both the mixed stain remover and the unmixed ones. Thanks for your help.
This is why I prefer to use two part stain removers which are Ammonia and Peroxide. The ammonia acts as a catalyst for the peroxide and starts the activation process. Once on the carpet or fabric, it does it's thing, then begins to break down and eventually become water.
