scope:

This standard describes chlorination materials, procedures, and requirements for disinfection of new treatment facilities and existing water treatment facilities temporarily taken out of service for cleaning, inspection, maintenance, painting, repair, or any other activity that might lead to contamination of water. Typically, these units include filter basins, filter media, clearwells, pump suction wells, and all associated piping and appurtenances located downstream from the filter influent or from the first point of application of disinfectant in the treatment process if process disinfection is initiated upstream of the filters. The disinfection method employed is surface contact with a high-strength chlorine solution for a specific time period. Proof that disinfection has been accomplished is provided by the results of bacteriological sampling and testing that show the absence of coliform organisms.

Purpose

The purpose of this standard is to define the minimum requirements for the disinfection of water treatment plants, including facility preparation, application of chlorine to the interior surfaces of water treatment units, and sampling and testing for the presence of coliform bacteria.