輻射佩章佩戴遵從性監測系統開發與測試

Abstract

在輻射暴露相關工作中常以輻射劑量佩章作為個人輻射暴露監測的測量儀器。然而，工作者在佩戴輻射劑量佩章時，常不依規定佩戴輻射劑量佩章，導致佩戴輻射劑量佩章的合規佩戴遵從性低，且佩章取得之數據也不足以正確代表受試者實際暴露劑量。因此，本研究欲開發能有效評估輻射劑量佩章合規佩戴遵從性的系統。 為了完成此目的，本研究分為兩部分。第一，測試三軸加速度計作為評估合規佩戴性工具的適合度，本研究設計四項實驗單元來確認三軸加速度計適合作為評估合規佩戴遵從性的工具，分別為靜置狀態穩定度測試、收樣頻率測試、佩戴位置測試、特定動作記錄樣態測試。第二，受試者在模擬場域中長時間佩戴三軸加速度計時三軸加速度計紀錄合宜性之評估。在第二部分研究中招募7名受試者進行為期一日的收樣，並且使用攝影機記錄受試者活動以作為黃金驗證標準。利用第一部分實驗單元得到之數據訂定出能將三軸加速度計取得之數據判讀為與影片記錄內容結果最相近的判讀基準。 本研究除了驗證不論將三軸加速度計置放於身體何處，皆能有效地區別出是否為被佩戴狀態外，也觀察到將移動觀察時間區段設為4分鐘來分析資料，並以三軸加速度計主要參考軸向量測角度標準差0.8°作為有無佩戴狀態的判斷基準，能判讀出與實際影片觀察未佩戴時間最相近的結果，兩者間差異值小於3%。使用此判讀基準來判讀數據將能夠評估大多數正常情形下的受試者佩戴遵從性監測數據，也確認了此輻射劑量佩章合規佩戴遵從性評估系統的有效性。 本評估系統在使用上簡單且快速，能取得更貼近實際暴露狀態的採樣樣本，協助職安人員實施更適當的預防措施，保障工作者的健康。

Radiation badge is often used as personal monitor for radiation exposure at work. However, workers who are required to wear radiation badges usually don’t comply with the rules of badge-wearing. This results in low compliance of radiation badge-wearing, and the monitored radiation dosage isn’t accurate enough to account for the exposure dosage of the worker. Therefore, this study was aimed to develop a device to effectively assess the compliance with the compulsory radiation badge-wearing regulation in order to ensure the effectiveness of radiation badge monitoring at workplace. To achieve this study goal, two parts of experiments were conducted. The first part was performed to test the suitability of accelerometer as a device for badge-wearing compliance assessment, and composed of four tests for stationary stability, sampling frequency, wearing position, and specific action recording pattern, respectively. The second was conducted to evaluate the suitability of accelerometer being worn by the study subjects for a period of time in the simulated radiation workplace for badge-wearing compliance assessment. Seven study subjects were recruited for one-day monitoring with accelerometer in this part of experiment, and a camera was used to record the study subjects'' real activities as gold standard for comparison. The data from the first part of experiment were used to derive the criteria in interpreting the monitored data obtained by accelerometer for radiation badge-wearing compliance by comparing with the results of the film recorded real activity. This study confirmed that accelerometers is an effective device in differentiating whether it is worn or not worn, regardless of where it is placed on the human body. Furthermore, it was observed that with moving observation time segment set at 4 minutes for data analysis, along with a standard deviation of 0.8° for the accelerometer''s main reference axial angle as the criteria in differentiating accelerator being worn or not being worn status, it is capable to interpret the monitored results for the not being worn time as close as to that shown in the film with difference less than 3%. Using these criteria to interpret the monitor data, the badge-wearing compliance of most subjects under general situations could be assessed and the validity of this monitoring system was therefore confirmed for assessing the radiation badge-wearing compliance. The monitoring system developed in this study is simple and fast to use. It could help obtain exposure samples reflecting closer to the real exposure situations and assist occupational safety personnel to implement more appropriate preventive measures to protect the health of workers.