ASTM D7168-21

5.1?This test method has not been evaluated for all possible matrices. Test method suitability should be determined on specific waters of interest.

1.1?This test method describes a solid phase extraction (SPE) procedure to separate ⁹⁹Tc from environmental water (non-process-related or effluent water samples). Technetium-99 beta activity is measured by liquid scintillation spectrometry.

1.2?This test method is designed to measure ⁹⁹Tc in the range of approximately 0.037 Bq/L (1.0 pCi/L) or greater for a one litre sample.

1.3?This test method has been used successfully with tap water. It is the users responsibility to ensure the validity of this test method for samples larger than 1 L and for waters of untested matrices.

1.4?Technetium-99 alternatively can be determined in water samples using Practice D8026.

1.5?The values stated in SI units are to be regarded as standard. The values given in parentheses are provided for information only and are not considered standard.

1.6?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 appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7?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.