Application of two on-site quantitative methods for the detection of total chlorine in the water in the hemodialysis industry

To observe the application of two instruments for the quantitative detection of total chlorine in the water in the hemodialysis industry, thereby evaluating the accuracy of the two tools and the consistency of their results, and evaluating their practical significance for the safety of hemodialysis treatment. Two methods, based on diethyl-p-phenylenediamine spectrophotometry and amperometric methods, were employed to detect the total chlorine concentration in running water and in activated carbon tank effluent. Correlation analysis was performed to evaluate the accuracy of the two instruments. The Bland–Altman test was used to evaluate the consistency of the two methods. The total chlorine tester showed high accuracy and good repeatability in terms of detecting the total chlorine concentration in running water and activated carbon tank effluent. The residual chlorine sensor had high accuracy and good repeatability for detecting the concentrations of total and free chlorine, respectively, in running water. When detecting the concentrations of total and free chlorine in the effluent of the activated carbon tank, the two test results showed a moderate correlation. The two detection methods had good consistency for the detection of total chlorine concentrations in running water and activated carbon tank effluent. The two reviewed methods can monitor changes in the total chlorine in running water and activated carbon tank effluent. It is important to take timely measures when the total chlorine concentration of the activated carbon tank effluent reaches a certain warning value, and therefore to better ensure the safety of hemodialysis treatment.