ASTM C1625-24

1.1 This test method covers the determination of the concentration and isotopic composition of uranium and plutonium in solutions. The purified uranium or plutonium fractions from samples ranging from nuclear materials to environmental or bioassay matrices is loaded onto a metal filament and placed in the mass spectrometer. The isotopic ratio is determined by thermal ionization mass spectrometry, and the concentration is determined by isotope dilution.

1.2 The values stated in SI units are to be regarded as the standard. Values in parentheses are for information only.

1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.