Each test strip has 10 chemical pads affixed to it. The reagent pads undergo a chemical reaction to the sample drop of urine that is placed on it. By waiting the appropriate number of seconds ~ from 30 seconds to 2 minutes for ThePetCheckup ~ you will obtain the test results.
The reason for reading the test in the suggested time frame is that the color will continue to develop. In chemistry, a reaction is always moving forward until stopped. When you put a drop of urine on the test pad, you start the reaction. You read the results at the cut-off time for that particular test pad, but the chemical reaction is still ongoing.
Our manufacturer uses the following examples, which I have always found helpful:
Banana analogy ~ It’s kind of like a banana that you have to eat in 2 or 3 days. The peel of the banana will get darker the longer it sits in the sun. It is the same thing with the test strips. Once you start the reaction, it will continue to the end result color, unless you read it at the appropriate cut-off time.
Pregnancy test analogy ~ Same thing with an over the counter pregnancy test. You have to read the results within the allotted time, otherwise you may get a false positive. This is because the reaction will be positive at time infinity no matter what.
by Bev Allen
https://thepetcheckup.com/
It is always better to prevent a disease,
or to catch it early, than to have to treat it at a later stage.
