The Radiological Traceability Program (RTP) is a Proficiency Testing (PT) program that establishes traceability for the Radiological and Environmental Sciences Laboratory (RESL), the Department of Energy’s (DOE) reference laboratory, to the National Institute of Standards and Technology (NIST).
The RTP provides an annual exchange of PT materials between NIST and RESL. It is designed to provide a mechanism for evaluating the ability of RESL scientists to prepare PT materials containing known activities of various radionuclides (Table 1), and to analyze materials of unknown activities in 6 matrices: air filters, vegetation, water, soil, synthetic urine, and synthetic feces.
Table 1. Radionuclides for the Radiological Traceability Program
|Th-230, U-238, U-234, Pu-238, Pu- 239/240, Am-241, Np-237||Alpha Emitting Radionuclides|
|H-3, Sr-90||Beta Emitting Radionuclides|
|Cs-137, Cs-134, Co-60, Mn-54, Co-57, Zn-65||Gamma Emitting Radionuclides|
|I-125, I-131||Isotopically Pure Radionuclides|
The objective of the Program is to conduct measurement traceability evaluations of the DOE RESL consistent with the ANSI N13.30, N42.22 and N42.23 standards. RESL is the designated reference laboratory for DOE and the Nuclear Regulatory Commission (NRC) Radiological Measurement Assurance Program (RMAP). As defined in ANSI N42.23-1996, RESL serves as a secondary reference laboratory to NIST and maintains direct traceability to NIST through the RTP. In this role, DOE has authorized RESL to prepare and distribute PT materials in a variety of sample matrices to laboratories that perform radiochemical analyses of environmental, bioassay, and other samples.
The RTP consists of two performance components:
Each result reported to NIST represents the activity added by NIST to the PT material, not the total activity contained in the sample. The natural background activity contained in a sample matrix is subtracted from all analytical measurements.