鈷六十治療機除役處置及人員劑量評估

Decommissioning of a Cobalt-60 Unit and Estimation of Exposure Dose to Person

林招膨(Jao-Perng Lin) ； 劉幕台(Mu-Tai Liu) ； 林桂華(Kui-Hua Lin) ； 黃勝賢(Sheng-Sang Huang) ； 林昇宏(Sheng-Horng Lin) ； 林松彥(Sung-Yen Lin) ； 葉啓源(Chi-Yuan Yeh) ； 莊庭禎(Tean-Jean Chuang)

《放射治療與腫瘤學》 5卷3期 (1998/09) Pp. 193-199

https://doi.org/10.6316/TRO/199805(3)193

摘要

目的：彰化基督教醫院放射腫瘤科規劃將原有之鈷六十遠隔治療機除役，以空出治療室做為安裝新直線加速器治療機之用。欲撤除之舊鈷六十治療機係屬醫用密封放射性物質，應由合格輻防專員監督執行整個除役拆機及運送安全程序。
材料與方法：在經行政院原子能委員會核準停用後，整個除役過程在轉射安全、應注意事項及處理步驟上皆依照原能會所頒訂之「放射性物質安全運送規則」及「游離輻射防護安全標準」辨理，並且針對拆機期間工作人員所受之輻射曝露擬定計劃特別曝露和評估其所受劑量。
結果：於做過嚴謹的沙盤演練後，在整個拆機、輻防作業規劃及管制採取合理抑低的原則下，順得地完成整個報廢移機手續。
結論：本文即針對鈷六十治療機的除役、運送過程中所需要做的準備及其劑量評估流程經驗做一詳實的描述。

關鍵字

輻防專員 ； 計盡特別曝露 ； 合理抑低

並列摘要

Purpose: The Department of Radiation Oncology at the Changhua Christian Hospital plans to retire the original cobalt-60 machine, and empty out the treatment room to install a new linear accelerator. The old cobalt-60 machine that will be removed is a sealed source for medical use. There should be a qualified radiation protection commissioner to supervise all procedures of dismantling the machine and the safety of transportation.
Materials and Methods: After gaining the approval of the Atomic Energy Council (AEC) at the executive yuan, all procedures concerning radiation protection, works should be considered and in line with the steps according to ”Regulations about the Security of Transporting Radioactive Materials” and ”Rules of Ionizing Radiation Security” which are issued by AEC. Aiming at the workers who received radiation exposures during the dismantling gauge planned special exposures and extimating the doses.
Results: After conscientious and careful practices, planning and controlling of radiation protection obey the rule of ALARA (as low as reasonable achievable) whole dismantling and transportation of the cobalt-60 machine was smoothly accomplished.
Conclusion: This paper describes the procedure about how to handle the retiring of a cobalt-60 machine and estimate personal dose fully and accurately.

並列關鍵字

Radiation Protection Commissioner ； Planned special exposures ； As low as reasonable achievable(ALARA)