Approved CWA Test Methods: Inorganic Non‑Metals
Methods approved under Clean Water Act section 304(h) and published at 40 CFR Part 136.
- 120.1: Conductance (Specific Conductance, μmhos, 25°C) by Conductivity Meter (pdf)
- 130.1: Hardness, Total (mg/L as CaCO3) (Colorimetric, Automated EDTA) by Spectrophotometer (pdf)
- 150.2: pH, Continuous Monitoring (Electrometric) by pH Meter (pdf)
- 160.4: Residue, Volatile (Gravimetric, Ignition at 550°C) by Muffle Furnace (pdf)
- 180.1: Determination of Turbidity by Nephelometry (pdf)
- 300.0: Determination of Inorganic Anions by Ion Chromatography; Rev. 2.1 (pdf)
- 300.1: Determination Of Inorganic Anions in Drinking Water by Ion Chromatography; Rev. 1.0 (pdf)
- 310.2: Alkalinity (Colorimetric, Automated, Methyl Orange) by Autoanalyzer (pdf)
- 335.4: Determination of Total Cyanide by Semi-Automated Colorimetry; Rev. 1.0 (pdf)
- 350.1: Determination of Ammonia Nitrogen by Semi-Automated Colorimetry; Rev. 2.0 (pdf)
- 351.1: Nitrogen, Kjeldahl, Total (Colorimetric, Automated Phenate) by Autoanalyzer (pdf)
- 351.2: Determination of Total Kjeldahl Nitrogen by Semi-Automated Colorimetry; Rev. 2.0 (pdf)
- 352.1: Nitrogen, Nitrate (Colorimetric, Brucine) by Spectrophotometer (pdf)
- 353.2: Determination of Nitrate-Nitrite Nitrogen by Automated Colorimetry; Rev. 2.0 (pdf)
- 365.1: Determination of Phosphorus by Semi-Automated Colorimetry; Rev. 2.0 (pdf)
- 365.3: Phosphorus, All Forms (Colorimetric, Ascorbic Acid, Two Reagent) (pdf)
- 365.4: Phosphorus, Total (Colorimetric, Automated, Block Digester AA II) (pdf)
- 375.2: Determination of Sulfate by Automated Colorimetry; Rev. 2.0 (pdf)
- 410.3: Chemical Oxygen Demand (Titrimetric, High Level for Saline Waters) by Titration (pdf)
- 410.4: The Determination of Chemical Oxygen Demand by Semi-Automated Colorimetry; Rev. 2.0 (pdf)
- 1627: Kinetic Test Method for the Prediction of Mine Drainage Quality (pdf)
- OIA 1677-09: Available Cyanide by Ligand Exchange and Flow Injection Analysis (FIA) (pdf)