医用直线加速器场所室内空气环境监测结果

Monitoring results of indoor air environment in medical linear accelerator room

目的观察医用直线加速器机房的基础空气环境与治疗出束期间治疗室内可吸入颗粒物(PM2.5)与总挥发性有机化合物(TVOC)的浓度变化情况。方法2019年2—3月采用米家空气质量检测仪对武汉市华中科技大学同济医学院附属同济医院肿瘤科放疗中心医用直线加速器控制室与治疗室的基础空气环境进行测量对比,同时测量治疗出束期间治疗室内PM2.5、和TVOC浓度变化。结果医用直线加速器治疗室和控制室的PM2.5浓度分别为(37.20±14.90)和(39.90±22.90)μg/m^3,明显低于室外环境(140.78±32.91)μg/m^3,室内TVOC值分别为(1.165±0.922)和(2.489±1.554)mg/m^3;在治疗出束期间治疗中心30~60 cm范围内,PM2.5指数明显升高,检测最大值范围区间(179.10~716.00)μg/m3,与照射野大小显著相关,3×3、5×5与10×10 cm射野大小的PM2.5指数最大值分别为304.70、449.00与和826.00μg/m^3,且与照射剂量有相关性。结论医用直线加速治疗室内PM2.5和TVOC的浓度与照射相关,不间断空气交换能有效降低治疗室内空气污染物浓度水平,放射治疗中照射所产生有害物质的浓度变化与应对措施,需引起放射工作人员重视。

Objective To observe the basic air environment of medical of medical linac machine room and the concentration changes of indoor particulate matter with particle size below 2.5 mic(PM2.5)and total volatile organic compounds(TVOC)during the treatment period.Methods From February to March 2019,Mijia air quality detector was used to measure and compare the basic air environment of the medical linear accelerator control room and the treatment room of the Radiotherapy Center of the Department of Oncology in Tongji Hospital Affiliated to Huazhong University of Science and Technology in Wuhan City.Meanwhile,PM2.5 and TVOC concentrations in the treatment room during the treatment beam were measured.Results PM2.5 concentrations in the treatment and control rooms of the medical linear accelerator were(37.20±14.90)μg/m^3 and(39.90±22.90)μg/m^3 respectively,which were significantly lower than that in the outdoor environm ent(140.78±32.91)μg/m^3.Indoor TVOC values were(1.165±0.922)mg/m3 and(2.489±1.554)mg/m^3 respectively.During the treatment beam release period,PM2.5 index was significantly increased in the range of 30-60cm in the treatment center,and the maximum detection range was 179.10-716.00μg/m^3,which were significantly correlated with the radiation field size.The maximum PM2.5 index values of the radiation field size of 3×3,5×5 and 10×10 cm were respectively 304.70,449.00 and 826.00μg/m^3,which were correlated with the radiation dose.Conclusion The concentration of PM2.5 and TVOC in medical linear acceleration treatment room is related to radiation exposure.Uninterrupted air exchange can effectively reduce the concentration of air pollutants in treatment room.The concentration changes and countermeasures of harmful substances generated by irradiation in radiation treatment should attract radiation workers'attention.