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Updated: Jul 2, 2026
06:08
Use of a Linear Accelerator for Conducting In Vitro Radiobiology Experiments
Published on: May 26, 2019
Long-term activation in a 15 MeV radiotherapy accelerator
1Health Physics Department, National Cancer Institute of Milan, Milan 20133, Italy.
Medical Physics
|August 14, 2008
Summary
Radioisotopes generated by medical linear accelerators can be measured using gamma-ray spectrometry. These activated metal components pose minimal shielding and storage challenges after decommissioning.
Area of Science:
- Nuclear Physics
- Medical Physics
- Radiochemistry
Background:
- Medical linear accelerators (LINACs) utilize high-energy electrons to produce photonuclear reactions.
- These reactions can lead to the activation of LINAC components, generating radioisotopes.
Purpose of the Study:
- To quantify the activity of radioisotopes present in the head of a decommissioned medical linear accelerator.
- To assess the implications for waste management and disposal.
Main Methods:
- High-resolution gamma-ray spectrometry was employed to measure activated isotopes.
- Activities of specific radioisotopes (e.g., 54Mn, 60Co, 65Zn) were directly measured.
- Activities of low-energy emitting isotopes were inferred using scaling factors.
Main Results:
- The study measured the activity of several radioisotopes, including 54Mn, 57Co, 60Co, 181W, and 65Zn.
- The mass and volume of activated components requiring special handling were found to be limited.
- The materials are metallic, facilitating radiation shielding.
Conclusions:
- Decommissioned LINAC components contain measurable radioisotopes.
- The characterized radioactive materials present manageable challenges for storage and disposal due to their limited mass, volume, and shielding properties.
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