Radiological Management of Air-fed Suit Work for Glovebox Dismantling Activities

During the glovebox dismantling activities, workers in air-fed suits would have been exposed to radioactive materials. In view of the potential exposure risk, a series of radiological control measures have been put in place. Prior to the commencement of glovebox dismantlement activities, a comprehensive radiological survey was conducted to ascertain the dose rates within the designated operational area. Based on these results, the external exposure doses to the workers were estimated throughout the course of the work. These estimates were incorporated into the work plan, wherein a management reference value for external exposure was defined. The external exposure dose to which the worker is subjected is limited by the continuous monitoring of the air dose rate in the operational area and the monitoring of the worker’s dosimeters. To prevent internal exposure for workers, the surface density of radioactive materials and the concentration of radioactive materials in the air are measured. Subsequently, respiratory and body protective equipment with an appropriate protection coefficient is selected, and a management reference value for internal exposure is defined. The inhalational hazard faced by the worker is managed by continuously monitoring measurement values that fall within the aforementioned management reference value. In this report, the radiological management activities are elucidated in detail, with concrete procedures and data from the dismantling of the liquid waste treatment gloveboxes previously performed.