What is the difference between residual chlorine, total chlorine and chloramines?
Free residual chlorine is fresh chlorine that is still able to sanitize and oxidize contaminants in the water. When testing for residual chlorine in rinse water, this form of chlorine is being tested. Chloramine (combined chlorine) is chlorine that has combined with contaminants. Chloramines have very little sanitizing ability and are not effective oxidizing agents. However, chloramines are commonly used to treat municipal water supplies. In the enclosed system they can be useful to sanitize the water. Therefore, feed water that is not treated to remove these potential contaminants can contain low levels of chloramines. These chloramines also create an unpleasant, strong chlorine odor. Total chlorine includes both free residual chlorine and chloramines.
