WaterWorks™ Free Chlorine test Strips combine a wide range of detection with our patented Free Chlorine indicator which does not bleach out even at levels above 2000 ppm. Designed to resist interference from monochloramines, WaterWorks™ Free Chlorine is the ideal product when testing in a food processing environment. With its detection sensitivity ranging from 0 - 25 mg/L, the Free Chlorine strip test is perfect for determining whether or not you have the correct amount of sanitizer present. All reagents are impregnated on the test strip pad, and no external chemicals are needed to perform this water quality test.