呼吸防護具密合度測試影響因素之探討

A Study on Factors Affecting Respirator Fit Testing

當前國內作業環境之現場員工所使用之呼吸防護具大多為國外廠商所製作，其防護具密合度測試過程與標準亦以外國人之一般臉型為主要考慮依據，國內已有㈻者研究指出，國內之一般人臉型與外國人（歐美人士）臉型有相當大之差異¸導致現場員工在配戴呼吸防護具時，可能無法完全密合，而有洩漏發生。本研究針對國內常見之半面式呼吸防護具，進行不同配戴臉型於不同吸氣流量﹑粒徑及死腔體積對防護具洩漏率之影響評估。結果發現，以國人模特大頭型配戴A、B、C 三種廠牌L 型號的呼吸防護具所產生的死腔體積分別為155、178、215cm3，死腔體積越大，洩漏率越低；同時洩漏孔到採樣點距離的長短，也是影響洩漏率實驗值的因素之一。本研究亦改變實驗操作之吸氣流量，以了解其對防護具洩漏率之影響，結果顯示，在所操作的流量範圍內，當吸氣流量增大時，洩漏率會有降低的趨勢，但下降的幅度則依呼吸防護具與配戴臉型的不同而有所差異。

The respirators used by Taiwanese workers are mostly manufactured by American or European companies . The respirator fit testing procedure and standard are based on facial shapes of Westners. It has been concerned that the facial shapes of oriental people are very different , therefore respirator leakage may happen when Chinese workers wear those respirators . Half-facepiece respirators were selected and evaluated to determine the effects of inhalation flow rate, particle size and dead volume on the respirator leakage. The dead volume was measured to be 155, 178, and 215 cm3 when the largest mannequin supplied by Institute of Occupational Safety and Health(IOSH) wore A , B and C company’s respirators , respectively. The respirator leakage was found to decrease with increasing dead volume. In the meantime , the sampling distance inside the respirator was found to affect the leakage rate.. In addition, the leakage decreased as the inhalation flowrate increased and the extent of leakage depended upon the respirator type and worker facial shape.