Analysis of individual doses to radiation workers from occupational external exposure in China in 2017 / 中华放射医学与防护杂志

ABSTRACT

Objective:To ascertain the levels of individual doses to radiation workers arising from occupationally external exposure in China in 2017, with an aim to provide basic data and scientific basis for prevention and control of occupational radiation sickness.Methods:Data on individual doses to monitored workers engaged in medical and industrial applications of radiation sources were collected through National Individual Dose Registry, with statistical analysis being carried out using Kruskal-Wallis H test, Mann-Whitney U test and Bonferroni method. Results:A total of 361 727 radiation workers were investigated in 2017, of which 81.6% was from medical application and 18.4% from industrial application, respectively. The average annual effective dose from medical and industrial applications were 0.353 and 0.270 mSv, respectively, with the former significantly higher than the latter ( Z=48.547, P<0.05). Furthermore, a statistically significant difference was seen in the average annual effective dose for each occupational category of medical application ( H=1 136.217, P<0.05), suggesting that the dose values for the monitored workers in nuclear medicine and interventional radiology were significantly higher than for other four medical categories ( Z=2.877-26.967, P<0.05). These dose values for the radiation workers was 0.361 mSv in tertiary hospitals, 0.397 mSv in secondary hospitals, and 0.308 mSv in primary and unrated hospitals, respectively. The dose values for the monitored workers in industrial radiography and well logging were significantly higher than for other five industrial categories of industrial applications ( Z=4.172-36.908, P<0.05). Conclusions:The average annual effective doses to the of monitored workers meet the relevant national standards. The exposure doses to the workers in nuclear medicine, interventional radiology, industrial radiography and well logging are relatively high. The necessary measures and devices for radiation protection should be further strengthened to reduce occupational exposure of workers.