Measuring UV‐absorbing organics: a standard method

Under the Information Collection Rule, water utilities across the United States will gather data on UV‐absorbing organics in an attempt to correlate this parameter with the occurrence of disinfection by‐products precursors. The method described here was prepared by the Joint Task Group for Method 5910. It will be included in the nineteenth edition of Standards Methods but is being published now so that it will be available for use with the Information Collection Rule. The method is intended to indicate the aggregate concentration of UV‐absorbing organics, which may possibly be correlated with precursors of disinfection by‐products. Details of the experimental method, results and discussion, and quality control are included, as well as a description of the principle of the method and interferences. Interlaboratory precision data are shown.