part_subject: "NATIONAL PRIMARY DRINKING WATER REGULATIONS"
subpart_code: "T"
subpart_subject: "Enhanced Filtration and Disinfection—Systems Serving Fewer Than 10,000 People"
section_number: "141.533"
section_subject: "What data must my system collect to calculate a disinfection profile?"
cfr_reference: "40 CFR 141.533"
title_name: "Title 40"
title_subject: "Protection of Environment"
parts_covered: "Parts 136 to 149"
revised_date: "Revised as of July 1, 2019"
publication_date: "As of July 1, 2019"
contains_description: "Containing a codification of documents of general applicability and future effect"
publication_info: "Published by the Office of the Federal Register National Archives and Records Administration as a Special Edition of the Federal Register"
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Your system must monitor the following parameters to determine the total log inactivation using the analytical methods in § 141.74 (a), once per week on the same calendar day, over 12 consecutive months:
(a)The temperature of the disinfected water at each residual disinfectant concentration sampling point during peak hourly flow;
(b)If your system uses chlorine, the pH of the disinfected water at each residual disinfectant concentration sampling point during peak hourly flow;
(c)The disinfectant contact time(s) (“T”) during peak hourly flow; and
(d)The residual disinfectant concentration(s) (“C”) of the water before or at the first customer and prior to each additional point of disinfection during peak hourly flow.