Mercury by cold vapor measurement context
EPA Method 245.1: the mercury in a digested sample is reduced to mercury vapor with stannous chloride and measured by cold vapor atomic absorption. A modified low-level version of 245.1 is also offered. Trace mercury uses EPA Method 1631: the sample is oxidized with bromine monochloride, the mercury is reduced and purged onto a gold trap, and it is measured by cold vapor atomic fluorescence. Water results are reported as µg/L, or ng/L for trace mercury. Solid samples are tested by EPA 7471B (cold vapor atomic absorption). Sample basis
Define the element list and fraction
Name the elements and state total, total recoverable or dissolved preparation as required. Filtration and preservation belong in the collection plan, and reporting limits must support the project criteria.
Include the complete project requirement
Provide the matrix, target analytes, required method, fraction, units and reporting limits. Include the permit or monitoring instructions where results will support a regulatory submission. Naming this method does not establish blanket compliance eligibility.
Resolve collection before sampling
Use the bottle, preservation and delivery instructions assigned to the agreed scope. Identify each location and collection time, and document any deviation. The final analytical plan must fit the submitted material and its intended use.
Related testing & guidance
Technical & service references
Vanguard service detailsSource review: November 8, 2026. The agreed method and project scope govern the testing.