ABSTRACT
Objective To determine the level of radiation dose in port workplace for loading and unloading natural uranium ore containers, and to provide a basis for occupational health management of the operators. Methods Workplace investigation was conducted to understand the loading and unloading process of natural uranium ore containers, operation time and frequency, etc. A radiation dose rate meter was used to detect the radiation dose rate at 5 cm from the outer surface of 168 natural uranium ore containers. At the same time, we selected one container and detected the level of dose rate at 5-200 cm away from each side surface of the 5 container surfaces except for the bottom side. Results The dose rate level at 5 cm at outer surface of 168 containers ranged from 27 μSv/h to 44 μSv/h, and the average dose rate level was 35.6 μSv/h. The average dose rate levels at 5, 30, 50, 100 and 200 cm were 21.3, 14.6, 11.3, 7.1 and 3.5 μSv/h, respectively. In normal operation, the personal exposure dose of port worker were estimated to be less than 580 μSv/a. Conclusion In normal operation, the dose rate level at any workplace on the outer surface of natural uranium ore container is far below the national standard limit.