Ho Chi Minh City University of Technology (HCMUT), Ho Chi Minh City, Vietnam.
Vietnam National University, Ho Chi Minh City, Vietnam.
Environ Geochem Health. 2023 Dec;45(12):9825-9836. doi: 10.1007/s10653-023-01773-8. Epub 2023 Oct 20.
In this study, the specific activities of Ra, Th and K in the unfired construction materials (solid card bricks, 4-hole bricks, pavement bricks) containing fly ash and bottom ash from a coal-fired thermal power plant in Vietnam were measured using the low-level gamma-ray spectrometer with HPGe detector. Also, the Rn concentrations in these materials were analyzed using RAD7 radon monitor and then radon mass exhalation rate and emanation fraction of these materials were calculated. The potential radiological hazards for residents living in the model room made of these materials were evaluated. The average specific activity of Ra, Th and K were found as 67.7, 79.3 and 703.5 Bq kg, respectively. The total annual effective dose (due to external gamma exposure and internal radon exposure for resident living in the CEN model room made of the unfired brick samples) was found as 0.9 mSv y which is lower than the worldwide average dose of 2.4 mSv y. Calculations from ResRad-Build code showed that the doses due to radon exposure account for from 62.3% (at the first year) to 98.8% (at the next 30 years) of the total gamma and radon dose. Under low air exchange to the outside environment, from the 6th year onwards, the total dose may exceed the average dose value from natural radiation exposure sources.
在这项研究中，使用带有 HPGe 探测器的低水平伽马射线光谱仪测量了来自越南燃煤热电厂的粉煤灰和底灰的未烧制建筑材料（实心卡砖、四孔砖、路面砖）中 Ra、Th 和 K 的比活度。此外，使用 RAD7 氡监测仪分析了这些材料中的 Rn 浓度，然后计算了这些材料的氡质量析出率和逸出分数。评估了由这些材料制成的模型室中居民的潜在辐射危害。发现 Ra、Th 和 K 的平均比活度分别为 67.7、79.3 和 703.5 Bq kg。由于居住在由未烧制砖样品制成的 CEN 模型室的居民的外部伽马辐射暴露和内部氡暴露，总年有效剂量（E）为 0.9 mSv y，低于全球平均剂量 2.4 mSv y。ResRad-Build 代码的计算表明，氡暴露引起的剂量占总伽马和氡剂量的 62.3%（第 1 年）至 98.8%（第 30 年）。在与外部环境的低空气交换下，从第 6 年开始，总剂量可能超过来自天然辐射源的平均剂量值。
