電腦周邊微環境空氣品質之探討

Abstract

本研究觀察在電腦運轉時於其周邊微環境中之常見室內空氣汙染物的濃度。選定三台使用半年以上之不同廠牌個人電腦，在距離電腦出風口風扇約10公分處以及距離主要入風口10公分處進行其周邊微環境之總粉塵、揮發性有機物 (pentane, butyl acetate, acetone, ethyl acetate, toluene, ethyl benzene, xylene and 1, 2, 4-trimethylbenzene)、細菌及真菌之採樣調查。 粒狀物的部份，使用GRIMM Dust Monitor對總粉塵四小時平均之採樣結果，以一般線性模式 (general linear model, GLM)分析顯示，主要入風口處和出風口處的質量濃度 (df=1, F=99.320, p<0.05)和數目濃度 (df=1, F=8.232, p<0.05)皆有顯著差異。但其結果與NIOSH標準採樣方法所得之結果不一致，因此目前的結果只指示電腦周邊微環境之主要入風口及出風口處之微粒質量濃度與數目濃度有顯著之不同，兩處何者之濃度較高則需進一步之研究。粒徑分布部份，出風口所含之微粒在粒徑範圍0.3-4.0 μm時有較入風口處較多的量；粒徑範圍4.0-20.0 μm時入風口處有較多的量。 揮發性有機氣體的部份，以Portable Dynamic Air Sampler-Solid Phase Microextraction (PDAS-SPME)採集氣態的揮發性有機化合物30秒，配合氣相層析質譜儀進行定量。檢測結果皆在出風口處發現有較多的量，其中ethyl benzene達到邊緣顯著(p=0.08, by Mann-Whitney U test)，其餘雖未達統計顯著，但皆呈現出口處之濃度大於入口處之趨勢。 細菌及真菌的部份，以安德森一階生物氣膠採樣器配合TSA與MEA培養基採樣20分鐘。結果顯示，真菌於出風口處之濃度有較高之趨勢。

This work aims to report the results of a field study with selected indoor air pollutants – total dust, selected five volatile organic compounds (VOCs), toluene, butyl acetate, ethyl benzene, xylene and 1, 2, 4-trimethylbenzene, bacteria and fungi - which may cause possible health risk for employees and visitors. Three personal computers (PCs) were selected as test products. For each studied pollutant, samples were collected simultaneously at two locations around a PC where near the major inlet and the outlet of a PC. For particulate matters sampled by GRIMM Dust Monitor, the sampling locations around a PC (the inlet and the outlet) can not be excluded to be a significant variable on variation of both the mass concentration (df=1, F=99.320, p<0.05) and the number concentration (df=1, F=8.232, p<0.05) by general linear models. However, it is hard to tell the mass concentration at the inlet would exceed that at the outlet in comparison to the result demonstrated by the NIOSH method 0500. There was an observable trend that the number concentration for particulates with size of 0.3-4.0μm was greater at the outlet than it at the inlet, but the concentration for particulates with size of 4.0-20.0μm was less at the outlet than it at the inlet. The concentrations of five VOCs obtained by Portable Dynamic Air Sampler-Solid Phase Microextraction (PDAS-SPME)show only the concentration of ethyl benzene at the outlet was greater than that at inlet with marginal significant difference (U=0.000, p=0.08) at the inlet and outlet of three PCs. The sampling of bioaerosol by the Andersen 1-stage impactor shows that the concentration of fungi was greater at the outlet than at the inlet.