ABSTRACT
Objective A case of abnormal personal doses of external exposure was reported in this paper. According to the investigation of the dose rates of the radiation sources and the workplace, the actualdose was estimated correctly. Methods The radiation level of storage containers at work site was measured by BH3103A portable X and γ radiation dosimeter. The thermoluminescence personal dosimeter was placed in the work site for a month, then it was measured with the RGD3 dosimeter to estimate the dose rateat the work site. The actual personal dose of external exposure was calculated based on the dose rateand the effective working time of the staff in the field. Results The location with highest dose rate was the empty containers which had been filled with raw materials. The second was a container filled with ingredients. The dose rate on the surface of empty container is generally higher than that of full container. The time weighted method was used to calculate the possible dose which was 2.32 mSv for this position. Conclusion The personal dose measured by the personal dosimeter was found to be erroneous, and it should be recorded with the revised dose of 2.32 mSv.