OPERATIONAL EXPERIENCE OF A TWO-DOSIMETER ALGORITHM FOR BETTER ESTIMATION OF EFFECTIVE DOSE AT KOREAN NUCLEAR POWER PLANTS

Two dosimeters are provided to radiation workers participating in tasks where high radiation exposure is expected during maintenance at nuclear power plants. At Korean nuclear power plants, two dosimeters are currently provided for tasks where exposure rates exceed 1 mSv/hr, the difference of equivalent dose to specific parts of the body is more than 30% and an exposure of more than 2 mSv is expected in a single task. These conditions for the provisioning of two dosimeters are based on previous field test results, and it is recommended that the dosimeters be worn on the chest and back. It was also found that the workers felt it was more convenient when they wore two dosimeters on chest and back rather than on chest and head. After the application of previous field test results to practice, it was found that the calculated effective dose for workers during radiation work was lower than the maximum dose of chest or back dosimeter by approximately 10%-30%. This performance is regarded not only to meet the international guideline but also to provide convenience for workers during radiation work.