| 摘要: | 本研究進行兩組實驗評估使用較低吸氣/吐氣阻力的供氣式呼吸防護具（supplied-air respirators, 以下簡稱SAR）相較於非動力淨氣式呼吸防護具（non-powered air-purifying respirators, 以下簡稱NAPR），對生理負荷及主觀不適之影響，實驗一條件為短時間（10分鐘）在兩種不同工作負荷（45W輕度工作、85W中度工作）進行實驗，以比較配戴SAR並設定三種不同流量（60、90、120 L/min）與NAPR之影響，實驗二則於兩種不同工作時間（短時間10分鐘、長時間40分鐘）進行實驗，比較配戴SAR（流量設定120 LPM）與NAPR之影響。兩個實驗主要應變項包括工作時心跳（HRwork）、工作心跳（WP）、耗氧量（VO2）、吸/吐氣壓力(PIP、PEP)、面罩內內罩溫度(IT)及主觀不適問卷（rate of perceptual exertion, RPE）程度，受試者分別為16與12位男性大專生。
研究的結果發現在相同的工作負荷及工作時間下，使用SAR相較於NAPR對工作心跳、耗氧量、面罩內內罩溫度、吸氣阻力及主觀不適程度皆有明顯下降，但在工作時心跳僅在實驗二長時間條件下明顯下降4~5 bpm。從實驗一發現於輕度工作45W下SAR所需要的供氣量最小為90 L/min，在中度工作85W則需要120 L/min對工作心跳、耗氧量才有明顯降低。由實驗二可知不管是使用SAR或NAPR對工作時心跳與工作心跳於作業前30分鐘有向上趨勢但30分鐘後後則趨於平緩，但在耗氧量在SAR與NAPR則隨著時間的增加分別平均約上升0.03~0.07 L/min及0.01 L/min。
在應用上使用SAR相較於NAPR對生理負荷及主觀不適是有明顯改善，並應考量不同的工作負荷設定不同供給流量，在長時間的作業上則建議應調整工作-休息時間，以避免造成過重的負荷。本研究中所使用SAR最大的缺點會限制了使用者的活動，研究結果可作為可針對可攜式動力式呼吸防護具之流量設定之參考。
Two experiments were conducted to assess the effects of using supplied-air respirator (SAR) that has lower breathing resistance compared with the usually employed non-powered air-purifying respirators (NAPR) on the effects of physiological loads and subjective discomforts. The first experiment compared SAR by using three different flows (60, 90, 120 L/min) with NAPR in two constant work load (light load 45W, moderate load 85W) in a 10-min ergometer cycling work. The second experiment compared SAR using constant flow 120 L/min with NAPR for short duration and prolonged work condition (10 min and 40 min). The evaluated dependent variables in both experiments included working heart rate (HRwork), work pulse (WP), oxygen consumption (VO2), peak inspiratory and expiratory pressure (PIP, PEP), inside inner quarter mask temperature (IT) and subjective rate of perceptual exertion (RPE). Sixteen and twelve physically fit male university students voluntarily participated in these two experiments.
Our results indicated that the use of SAR, compared with NAPR in the same work load and work time, significantly decreased WP, VO2, IT, PIP and RPE, except that HRwork, which significantly decreased 4~5 bpm only in the second experiment. In the first experiment, we found that the flow of SAR should be at least 90 L/min in the light work load and 120 L/min in moderate load to function effectively with significantly decreasing WP and VO2. The second experiment indicated that HRwork and WP increased significantly at the first 30min and stayed constant after for both SAR and NAPR. Furthermore, we found VO2 significantly increased for 0.03~0.07 L/min, 0.01 L/min for SAR and NAPR, respectively, during the prolonged condition.
This study indicates that the use of SAR can significantly decrease physiological load and RPE compared with NAPR. The flow setting of SAR should be carefully designed according to the work load. The work-rest ratios under the prolonged condition should also be adjusted to avoid excessive physiological load. The potable powered-air purify respirators (PAPR) may be a solution for the limited work area while using SAR. Our study may help the flow settings for the development of PAPR. |
