Chlor-Assure Chlorine Test Strip, 200ppm The Chlor-Assure Chlorine test strip measures Free Chlorine in increments of 0, 25, 50, 100,150, and 200ppm. This test strip can be used in conjunction with our Chlorine Test Paper as a confirmation. The Chlorine test paper is good for qualitative results, while the Chlor-assure test strip is better at quantitative results. The inexpensive paper strips are often used to monitor whether or not the solution is in the ballpark. Chlor-Assure and/or Mid-Level Chlorine test strips are more often used when you need to record results. For another free chlorine test alternative, check out our Mid-Level Chlorine Test Strips.