Approved CWA Chemical Test Methods
In addition to 40 CFR Part 136 methods, some approved industry-specific methods are published or incorporated by reference at 40 CFR Parts 401 through 503.
On this page:
- Approved methods listed by method number
- Approved methods listed by analyte (reference tables in 40 CFR 136.3)
Approved Methods Listed by Method Number
| Number | Method Title |
|---|---|
| 120.1 | Conductance (Specific Conductance, μmhos, 25 °C) by Conductivity Meter |
| 130.1 | Hardness, Total (mg/L as CaCO3) (Colorimetric, Automated EDTA) by Spectrophotometer |
| 150.2 | pH, Continuous Monitoring (Electrometric) by pH Meter |
| 160.4 | Residue, Volatile (Gravimetric, Ignition at 550 °C) by Muffle Furnace |
| 180.1 | Turbidity by Nephelometry. Revision 2.0 |
| 300.0 | Inorganic Anions by Ion Chromatography. Revision 2.1 |
| 300.1 | Inorganic Anions in Drinking Water by Ion Chromatography. Revision 1.0 |
| 310.2 | Alkalinity, Colorimetric, Automated Methyl Orange |
| 335.4 | Total Cyanide by Semi-Automated Colorimetry. Revision 1.0 |
| 350.1 | Ammonia Nitrogen by Semi-Automated Colorimetry. Revision 2.0 |
| 351.1 | Total Kjeldahl Nitrogen (Colorimetric, Automated Phenate) by Autoanalyzer |
| 351.2 | Total Kjeldahl Nitrogen by Semi-Automated Colorimetry. Revision 2.0 |
| 352.1 | Nitrogen, Nitrate (Colorimetric, Brucine) by Spectrophotometer |
| 353.2 | Nitrate-Nitrite by Automated Colorimetry. Revision 2.0 |
| 365.1 | Phosphorus by Semi-Automated Colorimetry. Revision 2.0 |
| 365.3 | Phosphorus, All Forms, Colorimetric, Ascorbic Acid, Two Reagent |
| 365.4 | Phosphorus, Total, Colorimetric, Automated, Block Digester, Automated Analyzer II |
| 375.2 | Sulfate by Automated Colorimetry. Revision 2.0 |
| 410.3 | Chemical Oxygen Demand (Titrimetric, High Level for Saline Waters) by Titration |
| 410.4 | Chemical Oxygen Demand by Semi-Automated Colorimetry. Revision 2.0 |
| 1627 | Kinetic Test Method for the Prediction of Mine Drainage Quality |
| OIA-1677-09 | Available Cyanide by Ligand Exchange and Flow Injection Analysis (FIA) • Regulatory history |
| Number | Method Title |
|---|---|
| 200.2 | Sample Preparation Procedure for Spectrochemical Determination of Total Recoverable Elements. Revision 2.8 |
| 200.5 | Trace Elements in Drinking Water by Axially Viewed Inductively Coupled Plasma-Atomic Emission Spectrometry. Revision 4.2 |
| 200.7 | Metals and Trace Elements in Water and Wastes by Inductively Coupled Plasma-Atomic Emission Spectrometry. Revision 4.4 |
| 200.8 | Trace Elements in Water and Wastes by Inductively Coupled Plasma-Mass Spectrometry. Revision 5.4 |
| 200.9 | Trace Elements by Stabilized Temperature Graphite Furnace Atomic Absorption Spectrometry. Revision 2.2 |
| 206.5 | Arsenic, Sample Digestion Prior to Total Arsenic Analysis by Silver Diethyldithiocarbamate or Hydride Procedures |
| 218.6 | Dissolved Hexavalent Chromium in Drinking Water, Groundwater, and Industrial Wastewater by Ion Chromatography. Revision 3.3 • Regulatory history |
| 231.2 | Gold, Atomic Absorption, Furnace Technique |
| 235.2 | Iridium, Atomic Absorption, Furnace Technique |
| 245.1 | Mercury in Water by Cold Vapor Atomic Absorption Spectrometry. Revision 3.0 |
| 245.2 | Mercury, Cold Vapor Technique, Automated |
| 245.7 | Mercury in Water by Cold Vapor Atomic Fluorescence Spectrometry. Revision 2.0 • Regulatory history |
| 252.2 | Osmium, Atomic Absorption, Furnace Technique |
| 253.2 | Palladium, Atomic Absorption, Furnace Technique |
| 255.2 | Platinum, Atomic Absorption, Furnace Technique |
| 265.2 | Rhodium, Atomic Absorption, Furnace Technique |
| 267.2 | Ruthenium, Atomic Absorption, Furnace Technique |
| 279.2 | Thallium, Atomic Absorption, Furnace Technique |
| 283.2 | Titanium, Atomic Absorption, Furnace Technique |
| 289.2 | Zinc, Atomic Absorption, Furnace Technique |
| 1631E | Mercury in Water by Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence Spectrometry. Revision E • Regulatory history |
| Number | Method Title |
|---|---|
| 420.1 | Phenolics, Total Recoverable, Spectrophotometric, Manual 4-AAP With Distillation |
| 420.4 | Total Recoverable Phenolics by Semi-Automated Colorimetry. Revision 1.0 |
| 525.1 | Organic Compounds in Drinking Water by Liquids-Solid Extraction and Capillary Column Gas Chromatography/Mass Spectrometry. Revision 2.2 |
| 525.2 | Organic Compounds in Drinking Water by Liquid-Solid Extraction and Capillary Column Gas Chromatography/Mass Spectrometry. Revision 2.0 |
| 601 | Purgeable Halocarbons |
| 602 | Purgeable Aromatics |
| 603 | Acrolein and Acrylonitrile |
| 604 | Phenols |
| 605 | Benzidines |
| 606 | Phthalate Ester |
| 607 | Nitrosamines |
| 608.1 | Organochlorine Pesticides in Municipal and Industrial Wastewater |
| 608.2 | Certain Organochlorine Pesticides in Municipal and Industrial Wastewater |
| 608.3 | Organochlorine Pesticides and PCBs by GC/HSD (replaces Method 608) |
| 609 | Nitroaromatics and Isophorone |
| 610 | Polynuclear Aromatic Hydrocarbons |
| 611 | Haloethers |
| 612 | Chlorinated Hydrocarbons |
| 613 | 2,3,7,8-Tetrachloro Dibenzo-p-Dioxin |
| 614 | Organophosphorus Pesticides in Municipal and Industrial Wastewater |
| 614.1 | Organophosphorus Pesticides in Municipal and Industrial Wastewater |
| 615 | Chlorinated Herbicides in Municipal and Industrial Wastewater |
| 617 | Organohalide Pesticides and PCBs in Municipal and Industrial Wastewater |
| 619 | Triazine Pesticides in Municipal and Industrial Wastewater |
| 622 | Organophosphorus Pesticides in Municipal and Industrial Wastewater |
| 622.1 | Thiophosphate Pesticides in Municipal and Industrial Wastewater |
| 624.1 | Purgeables by GC/MS (replaces Method 624) |
| 625.1 | Base/Neutrals and Acids by GC/MS (replaces Method 625)
• Validation of SPE Products & Associated Procedures with Method 625.1
|
| 632 | Carbamate and Urea Pesticides in Municipal and Industrial Wastewater |
| 1613B | Tetra- through Octa-Chlorinated Dioxins and Furans by Isotope Dilution HRGC/HRMS. Revision B • Regulatory History |
| 1624B | Volatile Organic Compounds by Isotope Dilution GC/MS |
| 1625B | Semivolatile Organic Compounds by Isotope Dilution GC/MS |
| 1664A | n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry. Revision A • Regulatory history |
| 1664B | n-Hexane Extractable Material (HEM; Oil and Grease) and Silica Gel Treated n-Hexane Extractable Material (SGT-HEM; Non-polar Material) by Extraction and Gravimetry. Revision B • Regulatory history |
Approved Methods Listed by Analyte
The lists of approved methods at 40 CFR 136.3, with footnotes, are provided here as a reference. To download specific method publications, refer to the tables.
- Lists of methods by analyte; from 40 CFR 136.3
- Table I B: Inorganics
- Table I C: Non-pesticide organics
- Table I D: Pesticides
- Table I F: Pharmaceutical
- Table I G: Pesticide active ingredients