Occupational exposure to ionizing radiation from medical practices in China has been collected for a 7 y period between 2010 and 2016 from roughly 220 individual monitoring service providers through the Chinese Registry of Radiation Workers. Statistical dose distributions and characteristic tendencies are presented based on the evaluation in terms of six occupational categories. A reduction can be seen in average annual effective dose for interventional radiology, nuclear medicine, diagnostic radiology, radiotherapy, dental radiology, and others by 52%, 47%, 46%, 34%, 69%, and 31%, respectively, for the 7 y period. More than 94.5% of radiation workers received annual doses less than the public dose limit (1 mSv) in 2016. Workers engaged in nuclear medicine and interventional radiology activities were found to receive relatively more dose than the other fields of practice. Diagnostic radiology makes the dominant contribution of 68% to the collective effective dose of 73,641.3 person mSv received by 211,613 radiation workers in medical practices in 2016. The observation of workers in medical practices receiving well below the recommended occupational dose limit (20 mSv) could be a result of an improvement in radiation protection practices in the medical field in China. However, it is still necessary to control and manage the workplace and radiation workers to avoid unnecessary exposures, in particular for the workers engaged in nuclear medicine and interventional radiology activities.

The national status and dose trends on the occupational exposure to ionizing radiation in industrial practices for 2009–2018 in China are presented in terms of seven occupational categories. A total of 504,538 industrial radiation workers were monitored for the period 2009–2018, with a continuous increase in the number of workers from 23,789 in 2009 to 66,017 in 2018. The annual average effective doses were 0.399, 0.425, 0.392, 0.376, 0.346, 0.355, 0.312, 0.305, 0.270, and 0.230 mSv from 2009 to 2018, respectively, which were well lower than the recommended occupational dose limit of 20 mSv y⁻¹ for radiation workers. The Mann-Kendall test result shows a statistically significant decreasing trend at a rate of 0.02 mSv y⁻¹ in average annual effective doses (p<0.001). In addition, more than 95.4% of radiation workers in industrial practices received an average annual effective dose less than the public dose limit of 1 mSv. It was also found that the average annual effective doses in industrial radiography and well logging were significantly higher than those in five other categories (p<0.001). Based on these observations, it is still necessary to control and manage the workplace and radiation workers to control occupational exposure as low as reasonably achievable, especially for the workers engaged in these two activities.

The personal dose levels of medical radiation workers in Chongqing from 2008 to 2020 were investigated and analysed. The results showed that a total of 68 379 people were monitored from 2008 to 2020. The number of radiation workers increased year by year, and the number of female radiation workers increased rapidly. The monitoring data were analysed by Mann–Whitney test, Mann-Kendall test and Bonferroni method. The annual mean effective dose from 2008 to 2020 showed a decreasing trend (P < 0.0001). At the 5% significance level, six occupational categories showed a significant decreasing trend (P < 0.0001).The average annual effective dose for medical radiation workers in Chongqing in 2020 was 0.4482 mSv and 94.73% of radiation workers received annual doses less than the public dose limit (1 mSv). Personal dose monitoring results for most radiation workers were low. The protection of radiation workers in interventional radiology and nuclear medicine should be concerned.

In recent years, China has experienced a notable increase in indoor radon concentrations. However, our understanding of residential radon exposure in Central China remains limited and primarily depends on the data collected from residential buildings in Wuhan before 2003. Given this context, the current radon exposure levels in Central China must be assessed immediately, and the factors influencing them be investigated. To address this gap, our study focused on five representative areas in Central China. We monitored indoor radon concentrations in residential areas using random cluster sampling while considering various building structures. The radon levels were measured through the alpha track method, and RSKS standard detectors were deployed in two separate batches to participating households. A total of 1300 detectors were distributed across 579 households, with a recovery rate of 97.15% (1263 detectors were retrieved). The annual average indoor radon concentration in Central China ranged widely from 6.25 Bq/m³ to 310.44 Bq/m³, with an arithmetic mean of 50.20 Bq/m³, which resulted in an average annual effective dose of 2.08 mSv. Referring to World Health Organization standards, the radon concentration in approximately 8.24% of the monitored rooms exceeded the recommended action level. Our analysis indicated that radon concentration is primarily influenced by factors, such as the time of measurement, geographical location, building structure, floor materials, household fuel, and ventilation practices. Multiple regression analysis revealed that these factors collectively account for 10.80% of the variation in radon concentration. Notably, geographical location, building structure, and ventilation mode emerged as important factors. Based on these findings, our study suggests several practical measures to effectively reduce indoor radon levels, including improving ventilation, switching to cleaner fuels, and using environmentally friendly building and decoration materials.