Extremity Dosimetry - doe-std-1128-98

DOE-STD-1128-98

The general methods used to calibrate the dosimeters are given in the National

Bureau of Standards Special Publication 633, Procedures for Calibrating Neutron

Personnel Dosimeters (Schwartz and Eisenhauer, 1982). Two laboratories

conduct the performance test irradiations for the DOELAP and NVLAP

programs: Pacific Northwest National Laboratory of Richland, Washington, and

the Radiological and Environmental Sciences Laboratory (RESL) of Idaho Falls,

Idaho. Dosimeters are submitted for testing to the performance testing

laboratories in specified categories. If the dosimeter passes certain accuracy and

tolerance testing criteria, a team of dosimetry experts visit the processor and/or

site and assess the operation of the dosimetry program, including dosimetry

records and data retrieval systems, before the dosimeter processor or DOE site is

accredited. DOE requirements are given in the U. S. Department of Energy

Standard Laboratory Accreditation Program for Personnel Dosimetry Systems,

DOE STD-1095- 95 (DOE 1995h). At present, both whole body personnel

dosimeters and extremity dosimeters are being tested, with extremity dosimeter

testing currently being voluntary. DOE will formalize the extremity dosimetry

accreditation program in the near future.

6.3.3

Extremity Dosimetry

Doses to the extremities from plutonium processing and handling can involve

significant exposures to the skin of the hands and forearms. Doses over small

areas of the skin are discussed in Section IV.B.2. of Implementation Guide.

External Dosimetry Program (DOE, 1999e) and will not be discussed here. That

Section discusses skin contamination including hot particles, and the

determination of skin dose from these events.

Highly accurate measurement of the dose to the hands and forearms is especially

difficult because of the low-energy photons (L x-rays and 60-keV photons from

241Am). Small variations in shielding, such as differences in the thickness of

gloves used in glove boxes or non-uniform distribution of plutonium oxide dust

on the surface of gloves, can produce large variations in the dose rate. Examples

of these variations were given previously.

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