Quality assurance of six cylindrical and two parallel plate chambers by radioactive check device: Influence of chamber age to its performance

Marjanovic Milana; Moravčević Jelena; Petrović Borislava

doi:10.1016/j.ejmp.2023.102635

Quality assurance of six cylindrical and two parallel plate chambers by radioactive check device: Influence of chamber age to its performance

Phys Med. 2023 Aug:112:102635. doi: 10.1016/j.ejmp.2023.102635. Epub 2023 Jul 20.

Authors

Marjanovic Milana¹, Moravčević Jelena², Petrović Borislava³

Affiliations

¹ Radiotherapy Department, Oncology Institute of Vojvodina, Put dr Goldmana 4, 21204 Sremska Kamenica, Serbia; Department of Physics, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia. Electronic address: marjanovic.milana@onk.ns.ac.rs.
² Radiotherapy Department, Oncology Institute of Vojvodina, Put dr Goldmana 4, 21204 Sremska Kamenica, Serbia. Electronic address: mancev.jelena@onk.ns.ac.rs.
³ Radiotherapy Department, Oncology Institute of Vojvodina, Put dr Goldmana 4, 21204 Sremska Kamenica, Serbia; Department of Physics, Faculty of Sciences, University of Novi Sad, Trg Dositeja Obradovića 3, 21000 Novi Sad, Serbia. Electronic address: borislava.petrovic@df.uns.ac.rs.

PMID: 37480711
DOI: 10.1016/j.ejmp.2023.102635

Abstract

Purpose: To evaluate the performances of eight ionization chambers, (two types) manufactured in a time span of 14 years, with radioactive source devices and photon beams.

Methods: The measurements were performed with six Farmer and two parallel plate ionization chambers with appropriate radioactive check devices and accompanying inserts. Some tests were performed with photon beams at linear accelerator. Physical visibility check, stability, linearity of response, directional dependence, determination of leakage current, ion recombination and polarity effect and influence of background radiation tests were conducted and analyzed.

Results: The performance of all Farmer ionization chambers was in agreement to IEC standard as well as for parallel plate type chambers. Long-term stability of older planparallel chamber was somewhat worse than expected.

Conclusion: Radioactive check devices have proven to be easy to use in clinical environment. According to results of this work Farmer type ionization chambers showed good quality regardless of the time of production, which make them long-term suitable for clinical dosimetry in radiotherapy. Also, for parallel plate type of ionization chambers the results showed fine agreement with the IEC standard, except long-term stability for older chamber, which needs further investigation.

Keywords: Ionization chambers; Quality assurance; Quality control; Radioactive check device.

MeSH terms

Particle Accelerators
Photons*
Radiometry*
Radiotherapy Dosage