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用ＦＡＲＭＥＲ剂量仪和ＦＪ３４７ＡＸ、γ剂量仪对８ 种型号的发射主射束Ｘ射线能量分别为４ ，６ ，８，１０ ，１５ 和１８ ＭＶ的１０ 台医用电子加速器治疗室内非主射束Ｘ射线辐射水平进行了测量。结果表明，在病人平面内，随等中心主射束Ｘ 射线剂量率的增加和照射野的增大，非主射束Ｘ射线辐射剂量率增加；随考查点到等中心距离的增加，非主射束Ｘ 射线辐射剂量率缓慢减少。可用ｆ＝ ４－６ ×１０－ ５Ｆ１２ Ｚ－ ３２ 关系估算辐射比。估算值与实测值符合较好，一般在３０ ％ 范围内。
Eight types of medical electron accelerators with main beam X-ray energies of 4, 6, 8, 10, 15 and 18 MV were irradiated with FARMER dosimeter and FJ347AX, γ dosimeter to treat indoor non-main beam X-ray Radiation levels were measured. The results show that the dose rate of non-main beam X-ray radiation increases with the increase of the X-ray dose rate of the main beam and the increase of the radiation field in the patient plane. With the increase of the distance from the examination site to the isocenter, Beam X-ray radiation dose rate slowly decreases. The radiation ratio can be estimated using the relationship of f = 4-6 × 10-5F12 Z-32. Estimated and measured values in good agreement, generally within the range of 30%.