With color matches at 0-200-400-600-1000-1500-2000 ppm (parts per million), the test paper measures concentrations between 0-2000 ppm, detecting exhaustion of solutions that should be replaced as well as helping to avoid using excessive amounts of sanitizing agents. Local health regulations require users of Quaternary Ammonium Sanitizer Solutions to have appropriate test kits available to verify the strength of sanitizer solutions. Sanitizer solutions are essential in the food service industry to ensure that sanitizers are at the proper concentration specified by the individual manufacturer.