某三甲医院^(131)I治疗场所辐射水平调查

Investigation on the radiation of ^(131)I in treatment site of a grade A tertiary hospital

目的对某三甲医院^(131)I治疗场所辐射水平进行检测,了解其辐射水平。方法25名甲癌患者共服用82880 MBq的^(131)I。患者服药后用X、γ射线测量仪检测病房周围剂量当量率;出院后用α、β表面污染仪检测病房表面污染;治疗期间和出院当天对^(131)I治疗场所及办公区进行空气采样,用高纯锗γ能谱仪测量空气样品,数据处理后得到空气中^(131)I浓度。结果^(131)I治疗病房周围剂量当量率为0.15~0.46μSv/h。病房清理前表面污染为0.53~40.1 Bq/cm^(2),其中马桶最高。患者服药后4 h内,^(131)I治疗场所及办公区走廊空气中^(131)I浓度分别为1.74 Bq/m^(3)和0.66 Bq/m^(3)。^(131)I治疗场所排风速率为0.50 m/s。患者治疗期间及出院当天,因通风导致空气中的^(131)I浓度分别较前一天下降29.7%、79.7%和53.3%。结论该场所外照射辐射水平较低且屏蔽效果较好;^(131)I治疗病房清理前表面污染除马桶略高于标准要求外,其余均低于标准限值;通风是降低该场所空气中^(131)I浓度的主要途径。

Objective To detect the radiation of ^(131)I in treatment site of a grade A tertiary hospital.Methods A total of 25 patients with thyroid cancer were administrated ^(131)I at a total dose of 82880 MBq.After administration,the ambient dose equivalent rate of the ward was detected with X-andγ-ray detectors.After patient discharge,surface contamination of the ward was detected withα/βsurface contamination meter.During patient hospitalization and on the day of discharge,air samples were collected from ^(131)I treatment site and office area.The air samples were measured using a HPGeγ-ray spectrometer and the concentration of ^(131)I in air was calculated.Results The ambient dose equivalent rate in the ward ranged from 0.15 to 0.46μSv/h.Before ward cleaning,surface contamination ranged from 0.53 to 40.1 Bq/cm^(2) and the highest value was recorded on the toilet.Within 4 h after administration,the concentrations of ^(131)I in air in treatment site and the corridor of the office area were 1.74 Bq/m^(3) and 0.66 Bq/m^(3),respectively.The ventilation air flow rate in the treatment site was 0.50 m/s.Ventilation decreased the concentration of ^(131)I in air by 29.7%,79.7%,and 53.3%compared with the previous day during hospitalization and on the day of discharge.Conclusion The radiation of external exposure of ^(131)I in the treatment site is low and the shielding is effective.Before ward cleaning,the surface contamination is lower than the required limits except for the toilet.Ventilation is the primary way to reduce the concentration of ^(131)I in air.