Kramer G H, Lee T Y, Lee J I, Chang S Y
Human Monitoring Laboratory, Radiation Protection Bureau, 775 Brookfield Road, Ottawa, Ontario, K1A 1C1, Canada.
Radiat Prot Dosimetry. 2001;95(1):31-5. doi: 10.1093/oxfordjournals.rpd.a006519.
Using ultrasound techniques, the Human Monitoring Laboratory has measured chest wall thicknesses of a group of male workers at the Korea Atomic Energy Research Institute. A site-specific biometric equation has been developed for these workers, who are somewhat smaller than other workers reported in the literature. Chest wall thickness is an important modifier on lung counting efficiency. These data have been put into the perspective of the ICRP recommended dose limits for occupationally exposed workers: 100 mSv in a 5-year period with a maximum of 50 mSv in any one year. For measured chest wall thicknesses of 1.9 cm to 4.1 cm and a 30 min counting time, the achievable MDAs for natural uranium in the KAERI lung counter vary from 6.6 mg to 13.2 mg. These values are close to, or even exceed, the predicted amounts of natural uranium that will remain in the lung (absorption type M and S) after an intake equal to the Annual Limit on Intake corresponding to a committed dose of 20 mSv. This paper shows that the KAERI lung counter probably cannot detect an intake of Type S natural uranium in a worker with a chest wall thickness equal to the average value (2.7 cm) under routine counting conditions.
利用超声技术，人体监测实验室测量了韩国原子能研究所一组男性工人的胸壁厚度。已为这些工人制定了特定部位的生物特征方程，这些工人比文献中报道的其他工人身材稍小。胸壁厚度是肺部计数效率的一个重要修正因素。这些数据已根据国际放射防护委员会（ICRP）对职业暴露工人的推荐剂量限值进行了分析：5年内100毫希沃特，任何一年最高50毫希沃特。对于测量的胸壁厚度为1.9厘米至4.1厘米且计数时间为30分钟的情况，韩国原子能研究所肺部计数器中天然铀的可实现检测下限（MDA）从6.6毫克到13.2毫克不等。这些值接近甚至超过了摄入相当于对应于20毫希沃特待积剂量的年摄入量限值后肺部（M型和S型吸收）中残留的天然铀预测量。本文表明，在常规计数条件下，韩国原子能研究所肺部计数器可能无法检测出胸壁厚度等于平均值（2.7厘米）的工人摄入的S型天然铀。
