Abstract
The Australian Radiation Protection and Nuclear Safety Agency (ARPANSA) maintains a 60Co teletherapy source primarily for the calibration of therapy dosemeters. The source and encapsulating head were replaced in early 2010 with an Eldorado 78 head and new 60Co source. In this article we present the results of ongoing accuracy and stability measurements since the replacement. A number of formal and informal indirect comparisons have been carried out with laboratories holding primary and secondary standards for 60Co. ARPANSA chambers have also been calibrated at international primary standard laboratories allowing comparison of calibration coefficients and thus 60Co absorbed dose standards. 60Co calibration coefficients supplied by manufacturers of chambers were compared to those measured at the ARPANSA when this calibration was traceable to a primary standard. ARPANSA also participates in an annual international mailed dosimetry audit conducted by the International Atomic Energy Agency. The results thus far demonstrate that the absorbed doses to water delivered by the new ARPANSA 60Co source are consistent with international doses within the stated uncertainties.
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References
Australian Institute of Health and Welfare (2014) Radiation oncology areas of need: cancer incidence projections 2014–2024 [Cancer series no. 85. (Cat. no. CAN 82)]. AIHW, Canberra
Barton M, Jacob S, Shafiq J, Wong KHW, Delaney G, Hanna T (2013) Review of optimal radiotherapy utilisation rates. Ingham Institute for Applied Medical Research, Liverpool
Ramanathan G, Harty P, Wright T, Lye J, Butler D, Webb D, Huntley R (2014) The Australian Primary Standard for absorbed dose to water (graphite calorimeter). ARPANSA Technical Report TR169
Lye J, Butler D, Franich R, Harty P, Oliver C, Ramanathan G, Webb D, Wright T (2013) Direct MC conversion of absorbed dose to graphite to absorbed dose to water for 60Co radiation. Radiat Prot Dosim 155(1):100–109
Kessler C, Burns DT, Allisy-Roberts PJ, Butler D, Lye J, Webb D (2012) Comparison of the standards for absorbed dose to water of the ARPANSA and the BIPM for 60Co gamma radiation. Metrologia 49:06009
Shimizu M, Morishita Y, Kato M, Tanaka T, Kurosawa T, Takata N, Saito N, Ramanathan G, Harty P, Oliver C, Wright T, Butler D (2014) Comparison of the NMIJ and the ARPANSA standards for absorbed dose to water in the high-energy photon beams. Radiat Prot Dosim. doi:10.1093/rpd/ncu272
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Oliver, C., Butler, D., Webb, D. et al. Maintaining the accuracy of the 60Co calibration service at the ARPANSA post source replacement in 2010. Australas Phys Eng Sci Med 38, 325–330 (2015). https://doi.org/10.1007/s13246-015-0338-5
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DOI: https://doi.org/10.1007/s13246-015-0338-5