National Center for Nuclear Safety and Radiation Control, EAEA, Cairo, Egypt.
J Environ Radioact. 2010 Mar;101(3):237-43. doi: 10.1016/j.jenvrad.2009.11.005. Epub 2009 Dec 14.
The field of radiation protection and corresponding national and international regulations has evolved to ensure safety in the use of radioactive materials. Oil and gas production processing operations have been known to cause naturally occurring radioactive materials (NORMs) to accumulate at elevated concentrations as by-product waste streams. A comprehensive radiological study on the oil refining industry in Egypt was carried out to assess the radiological impact of this industry on the workers. Scales, sludge, water and crude oil samples were collected at each stage of the refining process. The activity concentration of (226)Ra, (232)Th and (40)K were determined using high-resolution gamma spectrometry. The average activity concentrations of the determined isotopes are lower than the IAEA exempt activity levels for NORM isotopes. Different exposure scenarios were studied. The average annual effective dose for workers due to direct exposure to gamma radiation and dust inhalation found to be 0.6 microSv and 3.2 mSv, respectively. Based on the ALARA principle, the results indicate that special care must be taken during cleaning operations in order to reduce the personnel's exposure due to maintenance as well as to avoid contamination of the environment.
辐射防护领域及其相应的国家和国际法规已经发展到确保放射性物质使用的安全。众所周知，石油和天然气生产加工操作会导致天然放射性物质（NORM）作为副产物废物累积在高浓度处。对埃及炼油工业进行了全面的放射性研究，以评估该工业对工人的放射性影响。在炼油过程的每个阶段都收集了垢层、污泥、水和原油样品。使用高分辨率伽马谱仪测定了（226）Ra、（232）Th 和（40）K 的活度浓度。所测定同位素的平均活度浓度低于 IAEA 对 NORM 同位素的豁免活度水平。研究了不同的暴露情景。由于直接暴露于伽马辐射和吸入灰尘，工人的年平均有效剂量分别为 0.6 微希沃特和 3.2 毫希沃特。根据 ALARA 原则，结果表明，在清洁操作期间必须特别注意，以减少因维护而导致的人员暴露，并避免环境污染。
