X射线床旁摄片场所电离辐射水平和防护效果研究

A field research on the ionizing radiation level and protective effect in X-ray bedside radiography

目的研究X射线床旁摄片场所电离辐射水平和采取干预措施后的防护效果,为管理部门进一步制订管理标准提供依据。方法在上海市9个区随机抽取12家医疗机构的15台X射线床旁摄影机,模拟日常病房开展床旁摄影的场景,对观察点X射线周围剂量当量率进行检测和评估。结果在本研究所关注的范围内,床旁摄片场所X射线周围剂量当量率均超过本底值;不同设备(包括同型号但使用环境不同的设备)在相近的常规曝光条件产生的散射线剂量率差异较大,无防护屏场所的X射线周围剂量当量率在3.9 μSv/h至5 800 μSv/h之间;使用防护屏场所的X射线周围剂量当量率在0.095 μSv/h至22.1 μSv/h之间,明显低于无屏风的场所,铅当量高的防护屏具有更好的防护效果。结论不同型号的X射线床旁摄片机,自身防护性能差异较大,导致工作场所放射防护剂量的差别,购置防护性能好的设备、小心使用、做好维护保养工作等是降低X射线剂量的重要保障;开展床旁摄片时应当尽量疏散毗邻床位的病人、医务人员、探视家属等公众,对无法疏散的公众,建议使用便捷且实用的移动式防护屏。

Objective To study the level of ionizing radiation and the protective effects after taking intervention measures for the X-ray bedside radiography, and to provide the basis for further development of management standards. Methods A total of 15 bedside radiography sites from 12 medical institutions were randomly selected from the 9 districts in Shanghai. By simulating their daily working conditions, the dose equivalent rates at the observation points were monitored and evaluated. Results The dose equivalent rates around the bedside were all higher than the background in this study. Even at the similar exposure conditions ,the dose rate largely varied with the device. The range of the dose rate varied from 3.9μSv/h to 5800 μSv/h without any protective screens, while the range was only from 0.095 μSv/h to 22.1μSv/h with the use of protective screens. The higher the lead equivalent of the screen, the better the protective effect. Conclusion Different bedside X-ray equipment have different self-protective performance, which leads to the difference of radiation level in the workplace. Purchasing equipment with good protective performance, using carefully and doing well in maintenance are the important guarantees to reduce the radiation dose. The adjacent patients, medical staff and visitors are recommended to be evacuated when performing the bedside X-ray photography. For those who can not be evacuated, it is suggested to use a convenient and practicaland mobile protective screen.