Code of Federal Regulations, Title 10, 835.402 states that radiological workers who are likely to receive 100 mrem from intakes are required to be monitored for exposure. For the indirect bioassay for radiological workers exposed to nuclear material containing fission products, ⁹⁹Tc must be measured in urine samples.

1.1 This test method covers the determination of the concentration of technetium-99 in urine using inductively coupled plasma-mass spectrometry (ICP-MS). This test method can be used to support uranium enrichment and reclamation facility bioassay programs.

1.2 The minimum detectable concentration for this test method, using a quadrupole ICP-MS, is approximately 1.0 ng/L (0.62 Bq/L).

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 and health practices and determine the applicability of regulatory limitations prior to use.