Estimating and analysis of personnel doses from activated nuclides in radiotherapy place of a proton accelerator
10.3760/cma.j.issn.0254-5098.2016.08.015
- VernacularTitle:质子加速器放射治疗场所活化核素所致人员受照剂量估算与分析
- Author:
Xia LI
;
Yongzhong MA
;
Shijin WANG
- Publication Type:Journal Article
- Keywords:
Proton acceterator;
Radiotherapy;
Activation nuclides;
Radioactive activity concentration;
Doses estimation
- From:
Chinese Journal of Radiological Medicine and Protection
2016;36(8):630-633
- CountryChina
- Language:Chinese
-
Abstract:
Objective To ascertain the dose levels to personnel from the activation products in the radiotherapy place of a proton acceterator and to provide technical basis for protection design of the treatment place and the personnel's radiation protection.Methods A PROTEUS 235 proton therapy system was analyzed for the potentials to produce activated nuclides in the air during its operation.The concentrations of the main radionuclides and the resultant personnel doses were estimated.Results The activity concentrations of activated nuclides were 15O 4.1 × 10-2,13N 3.3 × 10-2,41 Ar 6.2 × 10-3 and 11 C 2.0 × 10-2 Bq · cm-3,respectively,in proton accelerator hall,whereas those in the proton beam radiotherapy room were only about 5％ of the corresponding values in the proton accelerator hall.The annual doses to the radiation workers from immersion external exposure due to air activation were less than 1 and 0.1 mSv,respectively,when entering the proton accelerator hall 5 and 30 min after beam stopping;whereas those were 1.3-2.0,0.7-1.2 and 0.3-0.6 mSv,respectively,when entering the therapy hall 0,5 and 15 min after beam stopping.Conclusions The personnel doses received from activated nuclides in the air in the radiotherapy place of a proton acceterator are unignorable.The contribution to doses from immersed external exposure of 15O,13N,41Ar and 11C should be taken into full considerations,with necessary protection measures needed.
