為了瞭解校園內學生餐廳生物氣膠現況以及桌面微生物污染狀況,本研究利用環檢所公告之室內空氣中細菌濃度及真菌濃度檢測方法,進行生物氣膠污染現況之調查與消毒探討,亦利用TSI-8554室內空氣質量監測儀進行現場檢測室內環境品質因子;桌面微生物依據擦拭法檢測菌落數並分析出餐廳桌面上的微生物含量,針對空氣與桌面透過消毒評估以保障師生用餐健康的環境;亦利用SPSS雙變數分析、單因子變異數分析、複迴歸、多重比較分析,進行細菌與真菌對於室內空氣環境因子之探討。調查結果顯示,經二氧化氯消毒劑批次消毒後,平日餐廳細菌殺菌率達49%,真菌平均濃度維持在建議值範圍內;得知生物氣膠在沒有人為因素干擾下具有累積性,其標準偏差SD會隨著時間增加SD升高。
平日上課期間餐廳使用時,細菌量會隨人員的增加而增加,細菌會藉由生命體釋放於空氣中,然而真菌會因為人員進出附著於生命體被帶離餐廳,也會被大氣稀釋而減少,但在通風較好的採樣位置,細菌數會受到風速的擾動而增高,風速21-30 ft/min情況下,室內空氣細菌濃度符合環保署公告之室內空氣品質建議值高達86%,得知有適當風速的通風條件下,可有效控制空氣中微生物濃度。在餐廳桌面部份,利用自製二氧化氯濕紙巾消毒十分鐘後細菌及大腸桿菌群殺菌率皆達94%以上,可維持3小時。學生餐廳內空氣中細菌主要優勢菌種為芽孢桿菌(Bacillus)、球狀菌(Micrococcus)以及葡萄球菌(Staphylococcus)。將消毒前後菌種進行判別,二氧化氯對芽孢桿菌殺菌率32%,葡萄球菌殺菌率86%,球狀菌在學生餐廳空間內較無殺菌能力,其中球狀菌與葡萄球菌皆由動物皮膚上可發現的。利用複式迴歸法所得平日批次消毒之公式,將平日環境因子帶入便可得知經過批次消毒後,菌落數是否超出建議值範圍。因此,學生餐廳不管是室內空氣或是桌面的消毒 ,若以二氧化氯消毒劑進行消毒殺菌工作即可達到品質之要求。 In order to understand the cafeteria bioaerosol status and microbial contamination of tables, this study focuses on the determination of indoor air bacteria and fungi concentration. Biological aerosol pollution status and disinfection was investigated using TSI -8554 to monitor on-site indoor air quality. Microbiological swab detection of the cafeteria tables and analysis of the number of colonies were done to determine and assess microbiological disinfection of air and tables in order to protect teachers and students by providing a healthy environment during meals. Also, SPSS bivariate analysis, single factor analysis of variance, multiple regression and multiple comparison analysis were done in this study to assess the bacteria and fungi in indoor air as environmental factors. Survey results show that the batch disinfection by chlorine dioxide has a daily rate of 49% sterilization of bacteria and fungi to maintain the average concentration within the recommended range. Bioaerosol in the absence of man-made disturbance factors are cumulative and its SD will increase over time.
Cafeteria use during weekdays shows that the amount of bacteria increases with the number of people as the bacteria is released in the air by the living body. However, because the fungus adheres to the body and people come and leave the dining room, concentration was reduced in the atmosphere through dilution. But sampling in the ventilation position resulted to a disturbance as the wind speed increased. But if the wind speed was 21-30 ft/min, bacteria in indoor air concentrations meet the indoor air quality. EPA recommended value of up to 86% and proper ventilation wind conditions can effectively control the concentration of microorganisms in the air. The tables in the cafeteria were cleaned with chlorine dioxide using home-made wet towels. Ten minutes after cleaning, disinfection rates were 94% or more and this can be maintained for 3 hours. The airborne bacteria in cafeterias were determined as Bacillus, Micrococcus and Staphylococcus. The bacteria were determined before and after disinfection. Chlorine dioxide sterilization rate of 32% was achieved for Bacillus, Staphylococcus sterilization rate of 86% and spherical bacteria in the student dining space achieved no disinfection. Spherical bacteria and Staphylococcus aureus which adhere on the skin can be found in animals. Using multiple regression method on the daily disinfectant batch formula during weekdays and measuring certain environmental parameters after disinfection proves that bacteria counts exceeded the recommended value range. Therefore, if chlorine dioxide was used for disinfection and sterilization, the cafeteria can meet the quality requirements as determined by indoor air quality and disinfection of tables.