2010 年代之後，居家照護和遠距醫療對手持式 X 光機的需求正在增加，然需探討輻射工作人員在操作區的職業曝露，故本研究針對牙科手持式數位 X 光機、胸部四肢手持式數位 X 光機的輻射安全探討，進行操作情境的輻射分布測量，據以探討對輻射工作人員職業曝露之潛在輻射風險影響，並提出便攜手持式數位 X 光機使用之建議與輻射防護措施以及輻射安全測試項目與方法建議，針對牙科（AG100）和胸部（CVXair）手持式數位 X 光機在常見的操作照射角度（0°，-20°，50°）和（0°，-90°）下的散射輻射分佈。使用頭部假體和 Duke 胸部假體作為散射假體，以 RTI Scatter Probe® 劑量計在在半徑為 50 和 100 cm，高度為 50, 100, 150 cm 水平面下以 15°的間隔測量。如果操作員在中心角為180±60 度的工作區操作，對於牙科設備，在半徑 50/100 cm 下，平均散逸輻射在照射角度為 0 度時所造成的劑量為 0.040/0.024 μGy，-20 度時的劑量為 0.056/0.041 μGy，50 度時的劑量為 0.318/0.162 μGy；另一方面對於胸部攝影設備，照射角度為 0 度時的劑量為0.275/0.130 μGy，-90 度時的劑量為 1.565/0.245 μGy。AG100 在使用頭部假體曝露於 cone tip 下為 2.0 mGy，估計散射輻射曝露，標準化空氣克馬率（μGy /mGy），轉換為每次成像散逸輻射（μGy）與 H*（10）的環境劑量，得到了10 mm 深度的周圍等效劑量 H*（10），周圍等效劑量隨使用照射角度上升 2-10 倍不等，協助者周圍等效劑量則介於 0.3 至 0.1.6 μGy。當照射角度不為 0 時，工作人員在手持式放射線攝影期間接收的輻射劑量是顯著的。CVXair 在距離靶中心，使用胸部假體曝露於射束出口下為 5.0 mGy，估計散射輻射曝露，得到 10 mm 深度的周圍等效劑量 H*（10），躺臥照射相較於站立照射，會造成操作者周圍等效劑量上升 5.6-1.9 倍不等，協助者周圍等效劑量則介於 0.3-0.2 μGy。操作人員工作量是依據 ICRP 118 號報告建議之每年平均 50 mSv 年劑量限制下，操作者每天可操作照射的張數以 AG100 的 0 度角估算，操作員在 50/100 cm 的距離可以拍攝到1700/2400 張；CVXair 的 0 度角攝影，在 50/100 cm 的距離可以拍攝到 217/459 張，因此在這些情況下，應該將距離輻射源 0.5 m 的區域指定為控制區域。因此為了減少不必要的操作者輻射曝露，保持與病人足夠的距離並使用更安全的照射角度和防護設備是非常重要的，操作者在使用手持式 X 光設備時應該具備足夠的輻射防護知識，避免採用大角度之 X 光投射以執行病患之造影，並合理分配工作量，或建議手持式數位 X 光機攝影配置防護器具以提供工作人員最大程度之輻射防護。

The needs of handheld X-ray machines are increasing for homecare and telemedicine after 2010s. In this study, we aim to investigate the scatter radiation distribution of dental（AG100） and chest （CVXair）handheld digital X-ray machines at each recommended operating projection angles (0°, -20°, 50°) and (0°, -90°). Using a head phantom and Duke chest phantom as the scatter objects, an RTI Scatter Probe® dosimeter was measured in intervals of 15° in the horizontal plane with radius of 50 cm and 100 cm at a height of 50, 100, 150 cm. If an operator works in a sectioned area with a central angle of 180±60 degrees and a radius of (50 cm/100 cm), for dental unit the mean stray radiation was (0.040/0.024) μGy for 0 degrees, (0.056/0.041) μGy for -20 degrees, and (0.318/0.162) μGy for 50 degrees, on the other hand, for chest unit was (0.275/0.130) μGy for 0 degrees, (1.565/0.245) μGy for -90 degrees respectively. Our results suggest that the doses of radiation received by staff during handheld radiography are significant when the projection angle is used. Using head and Duke chest phantoms as scatter phantoms, measurements were taken with an RTI Scatter Probe® dosimeter at intervals of 15° at radii of 50 and 100 cm, and heights of 50, 100, 150 cm above the horizontal plane. For dental equipment, at a 180±60 degree central angle of operation, the average scattered radiation doses at 0° were 0.040/0.024 μGy, at -20° were 0.056/0.041 μGy, and at 50° were 0.318/0.162 μGy, at radii of 50/100 cm. For chest imaging equipment, the doses at 0° were 0.275/0.130 μGy, and at -90° were 1.565/0.245 μGy. The doses for AG100, exposing the head phantom at the cone tip, were 2.0 mGy. Scattered radiation was estimated, and the air kerma rate was standardized (μGy/mGy), converted to per-image scattered radiation (μGy), and the environmental dose H*(10) was obtained at a depth of 10 mm. The surrounding equivalent dose varied 2-10 times with the imaging angle, while the assistant's surrounding equivalent dose ranged from 0.3 to 1.6 μGy. Significant radiation doses were observed when the imaging angle was not 0 degrees during handheld X-ray imaging.
For CVXair, the dose at the cone tip, were 5.0 mGy. Scattered radiation exposure was estimated, and the surrounding equivalent dose H*(10) was obtained at a depth of 10 mm. Compared to standing imaging, lying down caused the operator's surrounding equivalent dose to increase 5.6-1.9 times, while the assistant's surrounding equivalent dose ranged from 0.3 to 0.2 μGy. The workload for operators is based on the recommendations of ICRP Report 118, with an annual average dose limit of 50 mSv. Using AG100 at a 0-degree angle, operators could perform imaging of 1700/2400 images at distances of 50/100 cm. For CVXair at 0 degrees, imaging at distances of 50/100 cm could capture 217/459 images. Therefore, the area within 0.5 m of the radiation source should be designated as a controlled area in these scenarios.To minimize unnecessary operator radiation exposure, maintaining an adequate distance from the patient and using safer imaging angles and protective equipment are crucial. Operators should possess sufficient radiation protection knowledge when using handheld X-ray devices, avoid adopting large-angle X-ray projections for patient imaging, and allocate workload appropriately. Alternatively, it is recommended to configure protective devices for handheld digital X-ray machines to provide maximum radiation protection for personnel.

摘要 i
Abstract iii
致謝 v
目錄 vi
表目錄 viii
圖目錄 ix
第一章. 緒論 1
1.1 研究目的及動機 1
1.2 研究方法與步驟 1
1.3名詞解釋 2
第二章. 介紹與文獻回顧 4
2.1便攜手持式數位 X 光機簡介與使用現況 4
2.1.1便攜手持式數位X光機簡介 4
2.1.2國際使用現況 5
2.1.3台灣使用現況 10
2.2國際便攜手持式數位X光機輻射安全規範標準與類別項目 11
2.2.1國際便攜手持式數位X光機輻射安全規範標準 11
2.2.2國際便攜手持式數位X光機輻射安全規範類別項目 11
2.3手持X光機操作者的輻射曝露評估 13
3.3洩漏輻射量測 13
2.3.1 人員劑量佩章評估 13
2.3.2輻射源機械性要求與影像品質 15
2.3.3散逸輻射分析 16
第三章. 研究設計與方法 19
3.1量測系統架設 19
3.1.1手持式數位 X 光機機型 19
3.1.2散射假體 22
3.1.3操作角度距離選擇 23
3.2輻射源（X光的品質與量）評估 23
3.1.4量測設備 24
3.1.5背景輻射評估 24
3.4散逸輻射量測 25
3.4.1空間分布特性 25
3.4.2角度分布特性 26
3.5評估操作人員年劑量 29
第四章. 結果與討論 30
4.1量測系統架設 30
4.1.1實驗架設 30
4.1.2背景輻射 31
4.2輻射源（X光的品質與量）評估 32
4.3洩漏輻射量測 35
4.4散逸輻射量測 36
4.4.1空間分布特性 36
4.4.2角度分布特性 39
4.5評估操作人員年劑量 43
4.5.1距離差異 43
4.5.2屏蔽差異 48
第五章. 結論 52
參考文獻 53

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