Detect the strength of quaternary ammonium compounds in sanitizers. QAC QR5 Test Paper QAC QR5 Test Paper is used to detect the strength of quaternary ammonium compounds in sanitizers in just seconds. QAC Compounds exhibit microbicidal activity to most microbes at 200ppm concentration. Instructions: 1. Remove a test paper from the vial, being careful not to touch the strip anywhere other than where you grasp it with your fingertips. 2. Dip about 1? of test paper into the solution to be tested for 1 second. 3. Allow 5-10 seconds to develop, then compare to the color chart. NOTE: The test strips should be kept in closed vials when not used, out of direct sunlight, at room temperature.