Methods for radiation protection testing and evaluation of a self-shielded head and neck radiotherapy system
10.13491/j.issn.1004-714X.2024.06.001
- VernacularTitle:自屏蔽头颈部放射治疗系统辐射防护检测与评估方法
- Author:
Xiangjie MA
1
;
Qinghuan JIANG
1
;
Ya LIU
1
;
Yu ZHANG
1
;
Mingsheng LI
1
Author Information
1. National Institute for Radiological Protection, Chinese Center for Disease Control and Prevention, Beijing 100088 China.
- Publication Type:OriginalArticles
- Keywords:
Radiotherapy;
Self-shielding;
Radiation protection;
Dosimetry；ZAP-X
- From:
Chinese Journal of Radiological Health
2024;33(6):621-625
- CountryChina
- Language:Chinese
-
Abstract:
Objective To establish testing and evaluation methods for radiation shielding performance of a self-shielded radiotherapy system by measuring the radiation levels around the self-shielded head and neck radiotherapy system. Methods A total of 14 monitoring points were selected outside the restricted zone of the system. Under radiation conditions from five different fixed directions, an ion chamber survey meter was used to measure and identify the maximum ambient dose equivalent rate at the 14 points. The time-averaged dose rate was then calculated based on the workload. In accordance with relevant radiation protection standards, an instantaneous dose rate of 10 μSv/h and a time-averaged dose rate of 2.0 μSv/h were proposed as the criteria for shielding protection evaluation. Results Based on the ambient dose equivalent rates at the 14 monitoring points outside the restricted zone, the maximum instantaneous dose rate outside the restricted zone was 7.4 μSv/h. With a workload of 15 patients per day, the maximum time-averaged dose rate was 1.0 μSv/h, which can be used as the criteria for shielding protection evaluation. Conclusion By considering both instantaneous dose rate and time-averaged dose rate, a comprehensive safety assessment of the radiation shielding performance of a self-shielded radiotherapy system can be conducted.
