The Micro Essential Laboratory Hydrion test kits are specific in nature and are made to work with a specific Quat formulation.  QT-10 is made to work with 2 chain quat solutions where QT-40 is made to work with 4 chain quat solutions. 

 The chemical manufacture sometimes puts the testing range on the chemical label.  If the testing range is 200 ppm, you have a 2 chain quat and you would use QT-10 if the testing range says 150 – 400 ppm, you have a 4 chain quat and you would use QT-40.  If the label does not offer the ppm testing range, you need to look for the active ingredients 

 

The Hydrion QT-10 and QT-40 are for testing Quaternary Ammonia solutions, not ammonia solutions.  The test kits will not give an accurate reading for that chemical.

Hot water increases the speed of the chemical reaction in the test paper making the 10 second time for the dip give a false high reading.  The best way to test hot solutions is to remove a sample and let it cool off then come back to it when it has reached an appropriate temperature and run the test again.

Cold water slows down the chemical reaction in the test paper making the 10 second dip time provide a false low reading.  The best way to test cold solutions is to remove a sample and bring it someplace where it can warm up to the appropriate temperature for testing then run the test again.

Chlorine is a strong oxidant and blotting the excess solution from the test paper allows normal color development.  If you don’t blot\, the oxidation continues to develop, and you will get a false high reading.