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  1. Home
  2. Clean Water Act Analytical Methods
  3. Approved Chemical Methods

Approved CWA Test Methods: Metals

Methods approved under Clean Water Act section 304(h) and published at 40 CFR Part 136.
  • 200.2: Sample Preparation Procedure for Spectrochemical Determination of Total Recoverable Elements; Rev. 2.8 (pdf) (143.05 KB, 1989)
  • 200.5: Determination of Trace Elements in Drinking Water by Axially Viewed Inductively Coupled Plasma - Atomic Emission Spectrometry; Rev. 4.2 (pdf) (157.14 KB, October 2003, 600/R-06/115)
  • 200.7: Determination of Metals and Trace Elements in Water and Wastes by Inductively Coupled Plasma-Atomic Emission Spectrometry; Rev. 4.4 (pdf) (451.14 KB, 1994)
  • 200.8: Determination of Trace Elements in Waters and Wastes by Inductively Coupled Plasma – Mass Spectrometry; Rev. 5.4 (pdf) (558.32 KB, 1994)
  • 200.9: Determination of Trace Elements by Stabilized Temperature Graphic Furnace Atomic Absorption; Rev. 2.2 (pdf) (286.97 KB, 1994)
  • 206.5: Arsenic, Sample Digestion Prior to Total Arsenic Analysis by Silver Diethyldithiocarbamate or Hydride Procedures (pdf) (85.77 KB, 1978)
  • 218.6: Determination of Dissolved Hexavalent Chromium in Drinking Water, Groundwater, and Industrial Wastewater Effluents by Ion Chromatography; Rev. 3.3 (pdf) (133.59 KB, May 1994)
  • 231.2: Gold, Atomic Absorption, Furnace Technique (pdf) (76.6 KB, 1978)
  • 235.2: Iridium, Atomic Absorption, Furnace Technique (pdf) (78.23 KB, 1978)
  • 245.1: Determination of Mercury in Water by Cold Vapor Atomic Absorption Spectrometry; Rev. 3.0 (pdf) (188.71 KB, 1994)
  • 245.2: Mercury (Automated Cold Vapor Technique) by Atomic Absorption (pdf) (135.27 KB, 1994)
  • 245.7: Mercury in Water by Cold Vapor Atomic Fluorescence Spectrometry; Rev. 2.0 (pdf) (225.59 KB, February 2005, 821-R-05-001)
  • 252.2: Osmium, Atomic Absorption, Furnace Technique (pdf) (57 KB, 1978)
  • 253.2: Palladium, Atomic Absorption, Furnace Technique (pdf) (81.85 KB, 1978)
  • 255.2: Platinum, Atomic Absorption, Furnace Technique (pdf) (74.98 KB, 1978)
  • 265.2: Rhodium, Atomic Absorption, Furnace Technique (pdf) (75.55 KB, 1978)
  • 267.2: Ruthenium, Atomic Absorption, Furnace Technique (pdf) (56.92 KB, 1978)
  • 279.2: Thallium, Atomic Absorption, Furnace Technique (pdf) (78.74 KB, 1978)
  • 283.2: Titanium, Atomic Absorption, Furnace Technique (pdf) (75.34 KB, 1978)
  • 289.2: Zinc, Atomic Absorption, Furnace Technique (pdf) (78.44 KB, 1978)
  • 1631: Mercury in Water by Oxidation, Purge and Trap, and Cold Vapor Atomic Fluorescence Spectrometry; Rev. E (pdf) (1.54 MB, August 2002, 821-R-02-019)

Clean Water Act Analytical Methods

  • PFAS Methods
  • Methods Update Rules
  • Approved Chemical Methods
    • Inorganic Non‑Metals
    • Metals
    • Organic
  • Approved Microbiological Methods
    • Wastewater & Sewage Sludge
    • Ambient Water
  • Approved WET Methods
    • Acute
    • Chronic - Freshwater
    • Chronic - Marine/Estuarine
  • Approved Radiochemical Methods
  • Approved Industry-Specific Methods
  • Other CWA Methods: Chemical
  • Other CWA Methods: Microbiological
  • Other CWA Methods: Biosolids
  • Alternate Test Procedures
  • Regulatory History
Contact Us about CWA Analytical Methods
Contact Us about CWA Analytical Methods to ask a question, provide feedback, or report a problem.
Last updated on August 16, 2024
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