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摘要：目的 研究極地航線空勤人員(包括飛行員和空乘人員)所受宇宙輻射劑量,以評價其是否超過國家標準,確保空勤人員健康,保障飛行安全. 方法 采用外照射全身個人劑量監測胸章劑量計,對典型極地航線(北京-紐約)空勤人員(飛行員6名、空乘人員12名)的個人輻射劑量進行測定,以地面工作場所10個監測點所測得的輻射劑量作為對照組. 結果 極地航線飛行員組的年有效劑量為5.34 mSv/a,千小時有效劑量為(3.43±0.08)mSv/1000 h,極地航線空乘人員組的年有效劑量為6.06 mSv/a,千小時有效劑量為(2.94±0.14)mSv/1000 h,地面對照組分別為0.63 mSv/a及(0.07±0.02)mSv/1000 h,3組間差異均有統計學意義. 結論 極地航線飛行空勤人員的年有效劑量均未超過國家標準規定限值(20 mSv/a),極地飛行中宇宙射線輻射不會對空勤人員身體構成額外過量劑量,基本屬正常航線飛行,不必產生心理恐慌. Abstract： Objective To measure the cumulative cosmic radiation dose of aircrew in polar flight and to assess whether the dose exceeds the national standard in order to ensure flight safety and their health. Methods Photoluminescence (OSL) dosimeter and CR-39 solid track detector were used to measure the cosmic radiation dose contributed by photon and neutron. The individual effective dose of pilots (6 persons) and stewards (12 persons), who were in the typical polar flight route (Beijing-New York), were measured and compared with the control group whose values were gathered from 10 monitors on ground site. Results The 1000 h effective dose from the groups of pilot and stewards was (3.43±0.08) mSv/1000 h and (2.94±0. 14) mSv/1000 h respectively comparing to (0.07±0. 02) mSv/1000 h gathered from ground sites. The statistic showed significant differences among these 3 groups. The annual effective does was then respectively summarized as 5. 34, 6.06 and 0.63 mSv/a corresponding to above groups. Conclusions The annual effective dose of aircrew's