title: HML's whole body counter: measuring highly radioactive persons.
abstract: The National Internal Radiation Assessment Section's Human Monitoring Laboratory (HML) has the responsibility to measure persons who may become internally contaminated following an accidental or intentional release of radioactivity. In preparation for measuring individuals who may be highly internally contaminated, the HML has reconfigured and recalibrated its whole body counter for this event. The calibration was performed using Monte Carlo simulations and validated by experimental measurements. An equation was developed that related the counting efficiency as a function of photon energy and phantom-to-detector distance. The equation could predict efficiencies to within 10% or better. Dead time problems, as a result of high internal activities, have been minimized by having a variety of counting positions. Six example nuclides have been used (Co, Co, Y, Ba, Cs, and Am) to show what is achievable and what is not.
authors.affiliation: National Internal Radiation Assessment Section, Radiation Health Assessment Division, Radiation Protection Bureau, 775 Brookfield Road, Ottawa, Ontario, K1A 1C1. gary_h_kramer@hc-sc.gc.ca
authors.forename: Gary H
authors.initials: GH
authors.lastname: Kramer
authors.forename: Kevin
authors.initials: K
authors.lastname: Capello
authors.forename: Albert
authors.initials: A
authors.lastname: Chiang
authors.forename: Barry M
authors.initials: BM
authors.lastname: Hauck
mesh_terms: D001822:Body Burden; D002138:Calibration; D002170:Canada; D003198:Computer Simulation; D017076:Computer-Aided Design; D004867:Equipment Design; D019544:Equipment Failure Analysis; D008954:Models, Biological; D011868:Radioisotopes / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D014915:Whole-Body Counting / Q000295:instrumentation* / Q000592:standards*
chemical_list: D011868:Radioisotopes