241Am-Be中子源测井的辐射剂量估算与防护措施探讨

目的 调查研究²⁴¹Am-Be中子源测井过程中操作人员所受辐射剂量，探讨测井中子源的管理及防护对策。方法 通过对某公司操作现场观摩和现场测量，获取中子源表面γ剂量率、中子剂量率以及取源、运输、装源等过程的操作时间和距离等参数，计算²⁴¹Am-Be中子源测井过程中操作人员所受到的辐射剂量，分析操作人员所受个人有效剂量的来源和占比。结果 一次源罐检查、搬运和检测过程中的中子照射和γ射线照射的有效剂量分别为94.17 μSv和2.72 μSv，一次装源和取源的中子照射和γ射线照射的有效剂量分别为36.66 μSv和24.08 μSv，中子源一次测井全过程的中子照射和γ射线照射的有效剂量分别为130.83 μSv和26.80 μSv；按每年测井100次估算，则中子源测井总的年有效剂量为15.78 mSv。结论 某公司²⁴¹Am-Be中子源测井过程中操作人员所受剂量主要为中子照射剂量，需要加强中子源管理和采取有效的中子辐射安全管理与防护措施。

Radiation dose estimation and protective measure discussion of 241Am-Be neutron source logging

Objective To investigate the radiation dose to operators in the process of ²⁴¹Am-Be neutron source logging, and discuss neutron source management and protective measures for operators in well logging. Methods Through on-site observation and measurement of ²⁴¹Am-Be neutron source logging in a company, we obtained the surface γ dose rate and neutron dose rate of the neutron source, as well as the operating time and distance of various processes including source taking, transfer, and loading, calculated the radiation dose to operators in various processes, and analyzed the source and proportion of the personal effective dose to operators. Results The effective doses of neutron irradiation and γ irradiation were 94.17 μSv and 2.72 μSv, respectively, for the combined processes of source tank inspection, transfer, and detection; 36.66 μSv and 24.08 μSv, respectively, for source loading and unloading; and 130.83 μSv and 26.80 μSv, respectively, for the whole neutron source logging process. The total annual effective dose of neutron source logging was 15.78 mSv, as estimated by logging 100 times per year. Conclusion In the process of ²⁴¹Am-Be neutron source logging in the company, the effective dose to operators mainly arises from neutron irradiation. Therefore, it is necessary to strengthen neutron source management and take effective protective measures against neutron radiation.