An analysis of calibration coefficients measured in water and in air for Farmer-type cylindrical ionization chambers

• Authors: Wojciech Bulski , Piotr Ulkowski , Barbara Gwiazdowska , Joanna Rostkowska
• Languages of publication: EN

Abstracts

EN

A comparison of calibration coefficients of Farmer-type cylindrical ionization chambers calibrated in a Co-60 beam according to the IAEA Reports 277 and 398 formalisms.91 calibration coefficients measured in air and in water.The 398ND, W/277ND, W ratios were calculated, taking into account the wall material of the chambers. The correlation between 398ND, W and NK, ND, air277ND, W was made and the equations of the regression straight lines were determined.Calibration coefficients, determined according to the IAEA Report 398, are higher by about 1% than those determined according to the IAEA Report 277, and they depend slightly on the wall material of the chamber.The introduction of the IAEA dosimetry Report 398 resulted in an increase in the doses delivered to patients by about 1% as compared with the period of application of Report 277. The regression equations may assure increased accuracy in retrospective comparative calculation of doses according to both reports as compared with the correction based on mean percent values.

Keywords

EN

calibration; dosimeters; ionization chambers; radiotherapy; SSDL

• Publisher: Versita
• Journal: Polish Journal of Medical Physics And Engineering
• Year: 2008
• Volume: 14
• Issue: 2
• Pages: 113-121

Dates

published

1 - 1 - 2008

online

14 - 4 - 2009

Contributors

author

Wojciech Bulski

• Department of Medical Physics, Center of Oncology, 02-781 Warsaw, Roentgena 5, Poland

author

Piotr Ulkowski

• Department of Medical Physics, Center of Oncology, 02-781 Warsaw, Roentgena 5, Poland

author

Barbara Gwiazdowska

• Department of Medical Physics, Center of Oncology, 02-781 Warsaw, Roentgena 5, Poland

author

Joanna Rostkowska

• Department of Medical Physics, Center of Oncology, 02-781 Warsaw, Roentgena 5, Poland

References

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Identifiers

DOI

10.2478/v10013-008-0010-4