Direct Radiobioassay.

DOE-STD-1112-98

required if routine measurements are to be performed for DOE contractors in the measurement

category. This table contains the categories, radionuclides and minimum testing levels (MTLs)

for direct radiobioassay measurements. For each measurement category, a set of phantom

organs or phantoms will be sent to the participating laboratory to be quantitatively measured.

5.2.2.2 The performance testing laboratory will develop or procure calibration phantoms

having activities within the MTL list in Table I. These phantoms will be shipped to the

participating service laboratories. Phantoms used for the measurement categories are a bottle

manikin absorption (BOMAB) phantom for whole body counting, calibration lung sets for the

Lawrence Livermore National Laboratory (LLNL) torso phantom for lung counting, and the

ANSI N44.3 thyroid neck phantom for thyroid counting.

5.2.2.3 The service laboratory may choose to analyze one or all of the radionuclides in the

test phantom. For each radionuclide for which the DOE contractor requests accreditation, five

replicate results shall be reported. These results are derived by counting the phantom once in

the normal measurement configuration used for workers, removing the phantom from the

measurement configuration, and then repositioning the phantom into the normal measurement

configuration and repeating the process for a total of five times. For measurements of the lung

phantoms the service laboratory is expected to provide their own LLNL torso phantom, using

only the bare chest cover (no overlays) for the measurements. Repositioning shall mean the

complete removal of the phantom from the chair or counting position and the reassembly and

repositioning of the phantom prior to a recount. The service laboratory shall report data using

the software provided by the testing laboratory.

5.2.2.4 The service laboratory shall use the counting procedure and counting times normally

employed for analysis of that radionuclide in worker measurements. Any deviations from the

routine measurement protocol shall be documented in the report to the performance testing

laboratory.