The NIST Radiochemistry Intercomparison Program NRIP:
Traceability for Low-Level Radioanalytical Laboratories
In 1997 the Radioactivity Group established a traceability-testing program
for low-level radioachemistry measurements. Each year, four rounds of
evaluations are conducted with participating university, federal, national,
interest group, and contract laboratories. The matrices (water, soil sediment,
air filter, synthetic feces and synthetic urine) and activity concentrations
reflected common radioanalytical analyses performed by the participating
laboratories. Laboratories are issued Certificates of Traceability for the
evaluation results. The program has been implemented to meet the guidance for
traceability as defined under ANSI N42.23, ANSI N42.22, and
ANSI N13.30. These voluntary standards define a hierarchy of traceability
with an unbroken linkage to NIST. Under these standards, the evaluation
materials shall be composed of appropriate matrices (i.e., matrix categories
commonly analyzed by the laboratory) and consist of appropriate (commonly
encountered) activity concentration ranges. Current participants in the NRIP
program requested these traceability evaluations as part of their quality
assurance and performance improvement programs.
Sample Distribution
Five samples and three blank samples were distributed to each laboratory for
each evaluation round. The evaluation samples are spiked with 90Sr,
natural uranium, 238Pu, and 241Am. The radionuclide
concentration range for all evaluations is 0.03 Bq to 0.3 Bq per
sample. About a dozen laboratories participate in the exercises each year.
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Environmental Program
| Radioactivity Group
| Ionizing Radiation Division
 
Inquiries or comments:
kenneth.inn@nist.gov
Online: February 1998 - Last update: October 2002
|
