Testing for the presence or absence of chemical germicides in hemodialysis is a critical component to assure patient safety. It is necessary to verify early prepared solutions are being used and rinsed out of devices (water treatment systems, dialysis machines, hemodialyzers), and to make sure equipment is working properly to remove drinking water disinfectants. It is important to use tests and procedures that have FDA clearance for use specifically in hemodialysis or, in the case of chlorine, the recommended test for detecting residual free and total chlorine as referenced in the Standard Methods for the Analysis of Water and Wastewater. Products without specific labeling for dialysis should be avoided. Positive and negative controls should be included to validate testing.