Methods approved under Clean Water Act section 304(h) and published at 40 CFR Part 136.
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- 120.1: Conductance (Specific Conductance, μmhos, 25°C) by Conductivity Meter (PDF)(4 pp, 83 K, 1982)
- 130.1: Hardness, Total (mg/L as CaCO3) (Colorimetric, Automated EDTA) by Spectrophotometer (PDF)(5 pp, 106 K, 1971)
- 150.2: pH, Continuous Monitoring (Electrometric) by pH Meter (PDF)(5 pp, 84 K, December 1982)
- 160.4: Residue, Volatile (Gravimetric, Ignition at 550°C) by Muffle Furnace (PDF)(3 pp, 78 K, 1971)
- 180.1: Determination of Turbidity by Nephelometry (PDF)(11 pp, 97 K, August 1993)
- 300.0: Determination of Inorganic Anions by Ion Chromatography; Rev. 2.1 (PDF)(28 pp, 138 K, August 1993)
- 300.1: Determination Of Inorganic Anions in Drinking Water by Ion Chromatography; Rev. 1.0 (PDF)(40 pp, 385 K, 1997)
- 310.2: Alkalinity (Colorimetric, Automated, Methyl Orange) by Autoanalyzer (PDF)(5 pp, 98 K, 1974)
- 335.4: Determination of Total Cyanide by Semi-Automated Colorimetry; Rev. 1.0 (PDF)(17 pp, 200 K, August 1993)
- 350.1: Determination of Ammonia Nitrogen by Semi-Automated Colorimetry; Rev. 2.0 (PDF)(16 pp, 239 K, August 1993)
- 351.1: Nitrogen, Kjeldahl, Total (Colorimetric, Automated Phenate) by Autoanalyzer (PDF)(8 pp, 160 K, 1978)
- 351.2: Determination of Total Kjeldahl Nitrogen by Semi-Automated Colorimetry; Rev. 2.0 (PDF)(16 pp, 239 K, August 1993)
- 352.1: Nitrogen, Nitrate (Colorimetric, Brucine) by Spectrophotometer (PDF)(5 pp, 78 K, 1971)
- 353.2: Determination of Nitrate-Nitrite Nitrogen by Automated Colorimetry; Rev. 2.0 (PDF)(15 pp, 234 K, August 1993)
- 365.1: Determination of Phosphorus by Semi-Automated Colorimetry; Rev. 2.0 (PDF)(18 pp, 390 K, August 1993)
- 365.3: Phosphorus, All Forms (Colorimetric, Ascorbic Acid, Two Reagent) (PDF)(5 pp, 87 K, 1978)
- 365.4: Phosphorus, Total (Colorimetric, Automated, Block Digester AA II) (PDF)(6 pp, 127 K, 1974)
- 375.2: Determination of Sulfate by Automated Colorimetry; Rev. 2.0 (PDF)(14 pp, 273 K, August 1993)
- 410.3: Chemical Oxygen Demand (Titrimetric, High Level for Saline Waters) by Titration (PDF)(4 pp, 98 K, 1978)
- 410.4: The Determination of Chemical Oxygen Demand by Semi-Automated Colorimetry; Rev. 2.0 (PDF)(13 pp, 224 K, August 1993)
- 1627: Kinetic Test Method for the Prediction of Mine Drainage Quality (PDF)(37 pp, 662 K, December 2011, EPA-821-R-09-002)
- OIA 1677-09: Available Cyanide by Ligand Exchange and Flow Injection Analysis (FIA) (PDF)(28 pp, 340 K, 2010)