Can the Quick Response QAC (QAC-400) test strips be used to test clean surfaces by first dipping the strip in distilled water, and then pressing on a dry, cleaned food contact surface to obtain a result?
Answer: The QAC QR test strips and color chart were developed for use in water solutions, such as a three sink setup. They might detect qac residual on surfaces as described above, however, the color response won’t correlate to the color chart. The indicator in the test paper is fairly sensitive. It might work but it would need to be evaluated carefully.