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Title 40

Displaying title 40, up to date as of 7/10/2026. Title 40 was last amended 7/09/2026.
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Title 40Protection of EnvironmentPart / Section
Chapter IEnvironmental Protection Agency1 – 1099
Subchapter DWater Programs100 – 149
Part 141National Primary Drinking Water Regulations141.1 – 141.905
Subpart AGeneral141.1 – 141.6
Subpart BMaximum Contaminant Levels141.11 – 141.13
Subpart CMonitoring and Analytical Requirements141.21 – 141.29
Subpart DReporting and Recordkeeping141.31 – 141.35
Subpart ESpecial Regulations, Including Monitoring141.40 – 141.42
Subpart FMaximum Contaminant Level Goals and Maximum Residual Disinfectant Level Goals141.50 – 141.55
Subpart GNational Primary Drinking Water Regulations: Maximum Contaminant Levels and Maximum Residual Disinfectant Levels141.60 – 141.66
Subpart HFiltration and Disinfection141.70 – 141.76
Subpart IControl of Lead and Copper141.80 – 141.93
Subpart JUse of Non-Centralized Treatment Devices141.100 – 141.101
Subpart KTreatment Techniques141.110 – 141.111
Subpart LDisinfectant Residuals, Disinfection Byproducts, and Disinfection Byproduct Precursors141.130 – 141.135
Subparts M-N [Reserved]
Subpart OConsumer Confidence Reports141.151 – 141.156
Subpart PEnhanced Filtration and Disinfection—Systems Serving 10,000 or More People141.170 – 141.175
Subpart QPublic Notification of Drinking Water Violations141.201 – 141.211
Subpart R [Reserved]
Subpart SGround Water Rule141.400 – 141.405
Subpart TEnhanced Filtration and Disinfection—Systems Serving Fewer Than 10,000 People141.500 – 141.571
Subpart UInitial Distribution System Evaluations141.600 – 141.605
Subpart VStage 2 Disinfection Byproducts Requirements141.620 – 141.629
Subpart WEnhanced Treatment for Cryptosporidium141.700 – 141.723
Subpart XAircraft Drinking Water Rule141.800 – 141.810
Subpart YRevised Total Coliform Rule141.851 – 141.861
Subpart ZControl of Per- and Polyfluoroalkyl Substances (PFAS)141.900 – 141.905