本研究針對使用連續進料的數值控制工具機台(Computer Numerical Control, CNC)之金屬加工作業場所，進行具有局部排氣功能的油霧回收機，對於細菌生物氣膠之移除效能的研究調查。研究中以MAS-100生物氣膠採樣器採集局部排氣裝置未運轉及運轉中的細菌生物氣膠，以APITM鑑定套件進行鑑定；同時以風罩風量計測定油霧回收機出口處的風量，以及使用直讀式雙通道粉塵計測定粉塵粒數濃度。連續進料CNC機台的金屬加工作業環境中，其細菌濃度皆低於戶外測值，也低於環保署規範的室內空氣品質標準1,500 CFU/m3。其機台出料口的細菌的移除效能為21.2%，機台前門測點的細菌的移除效能為12.8%；菌種鑑定之後發現以Staphylococcus hominis為其優勢菌種。在連續作業進行中，出料口dp介於2.5～5 μm的粉塵粒數濃度，未使用油霧回收機為76,256±34,743粒數/L，使用之後大幅度降至1,014±362粒數/L；至於dp>5.0 μm的粉塵粒數濃度，使用油霧回收機後由11,534±9,784粒數/L降至150±50 粒數/L。本研究發現連續進料CNC機台裝設油霧回收機後，能夠有效移除油霧液滴，並降低室內細菌生物氣膠濃度，使其低於室外測值。

This study is to survey the efficiencies of oil mist collector to remove the bacterial bioaerosols emitted from tunnel type computer numerical control (CNC) machine using metalworking fluids. Bacterial bioaerosols near the CNC machine were collected by MAS-100. The colonies were identified using API identification kit. The air flow rate was measured at the vent of the oil mist collector, and the particle concentrations were determined by the dual-channel direct-reading dust meter. The bacterial concentrations in the tunnel type CNC machine working environment were lower than 1,500 CFU/m3, the indoor air quality standards regulated by Taiwan EPA. The removal efficiencies of bacterial bioaerosols were 21.2% and 12.8% at the discharge port of the tunnel and in front of the closed door, respectively. Staphylococcus hominis was found to be the dominant identified strains. After oil mist collector turned on, particulate matter size in range of 2.5~5.0 μm concentrations 453 were decreased from 76,256±34,743 #/L to 1,014±362 #/L and from 11,534±9,784 #/L to 150±50 #/L for particulate matter size larger than 5.0 μm. The oil mist collector could not only remove the oil mist but also decrease the bacteria bioaerosols. Therefore, the concentrations of bacteria bioaerosols emitted from tunnel type CNC and in metalworking workplace were lower than those of outdoors.