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The Intercomparison Studies Program for in-vitro bioassay located at Oak Ridge National Laboratory (ORNL) has been in place since May 1991. The program was originally created to fill a need in the Radiobioassay area at ORNL, specifically in the areas of Quality Control, Quality Assurance, and Performance Testing. However, it soon became obvious, that if the program was to have any validity (NIST traceability for urine not being an option at that time), the QC spike samples needed to be analyzed by more than one bioassay facility in order to verify the accuracy of the spike. In the beginning, this consisted of two or three laboratories working in a "pilot" program. However, once it was determined that it could work effectively, the program began to seek additional members to cross-check the various bioassay samples. The program became formalized with a quarterly report and a regular cost-per-sample January 1, 1992. The program provides cross-check blind/double-blind urine samples spiked with known amounts of radioactivity to various DOE facilities throughout the United States. These samples can be packaged according to ORNL procedures i.e., ORNL sample bottles, ORNL chain-of-custody forms, tamper seals, etc., or according to the needs of a particular facility if the double blind sample mode is to be maintained. The Intercomparison Studies Laboratory is set up to function in the same manner as a routine bioassay facility. This includes having the capability to perform all the separations and analyses that would be carried out in a typical radiobioassay laboratory, along with the necessary policies, procedures, and document controls that go along with these techniques. The Intercomparison Studies Laboratory also maintains archive samples which can be analyzed in the laboratory at the request of any of the participating laboratories if a conflict or discrepancy in a sample analysis/result occurs. Radionuclides and the spike levels available are listed on the right. All radionuclides are NIST (National Institute of Standards and Technology) or NPL (National Physical Laboratory) standards with the following exception: Nat-Th is an Analytics standard. Blank samples (urine samples which have not been spiked with radioactivity) are also provided as cross-check samples. In addition, samples which are not in the above ranges can be provided if special arrangements are made. Below are examples of the types of statistical analyses/results. These are published once per quarter: (1) A short term report consisting of intercomparison data from the last quarter (2) A report of each laboratory's individual data Note: The quarterly report is published three months after the last spike sample to be included in the report has been shipped to the service laboratory. This is so that the service laboratories have time to process their samples, complete their analyses, and relay the data to the testing facility. Fecal Program: Paticipation in the Fecal Program is usually on a quarterly basis. The following isotopes will be available at two different spike levels (less than 1 dpm/sample and 1-5 dpm/sample with each sample weighing approximately 30 grams): The results from the fecal program will be included in a quarterly report similar to that established for the urinalysis program. Whole Body Count Program: On a quarterly basis, a set of 5 samples is prepared quarterly that contain 0.1 molar HCl spiked with known activities of gamma standards. These samples are placed in phantoms that have been provided to participants and counted. The spectral range from 122 keV to 1836 keV (useful whole body counting range) is examined. The results from the whole body count program are published in an annual report. |
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Email: Ged Payne Phone: 865-574-5014 Fax: 865-576-6316
