Wisconsin Administrative Code
Department of Natural Resources
NR 800 - Environmental Protection - Water Supply
Chapter NR 810 - Requirements for the operation and maintenance of public water systems
Subchapter IV - Inactivation Toolbox Components and CT Tables
Section NR 810.53 - CT table for viruses when using free chlorine
Universal Citation: WI Admin Code § NR 810.53
Current through August 26, 2024
CT Values for Inactivation of Viruses by Free Chlorine
| Log Inactivation | ||||||||||||
| Temperature, °C | 1.0 pH | 2.0 pH | 3.0 pH | 4.0 pH | ||||||||
| 6 - 9 | 10 | 6 - 9 | 10 | 6 - 9 | 10 | 6 - 9 | 10 | |||||
| 0.5 | 3 | 23 | 6 | 45 | 9 | 66 | 12 | 90 | ||||
| 5 | 2 | 15 | 4 | 30 | 6 | 44 | 8 | 60 | ||||
| 10 | 2 | 11 | 3 | 22 | 4 | 33 | 6 | 45 | ||||
| 15 | 1 | 8 | 2 | 15 | 3 | 22 | 4 | 30 | ||||
| 20 | 1 | 6 | 1 | 11 | 2 | 16 | 3 | 22 | ||||
| 25 | 1 | 3 | 1 | 7 | 1 | 11 | 2 | 15 | ||||
Disclaimer: These regulations may not be the most recent version. Wisconsin may have more current or accurate information. We make no warranties or guarantees about the accuracy, completeness, or adequacy of the information contained on this site or the information linked to on the state site. Please check official sources.
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