The Extra High Level QAC Test Strip (Quaternary Ammonium Compounds) measures the range of 0-10,000 ppm in increments of 1000, 2500, 5000 and 10000 ppm, and gives results in just seconds. Check for higher levels of QAC when testing stronger solutions that kill pathogenic organisms, as opposed to testing for residual QAC with our Low Level QAC test strip, or our standard QAC Quick Response Test Strip.