Impacts of ultrasonic humification on size-distribution and concentration variations of indoor bioaerosol and its optimization strategy
CHEN Lu-an1, YANG Chuan-jun1, GU Yu-qian1, LIU Xue-hu2, YANG Zi-li1
1. College of Environmental Science and Engineering, Donghua University, Shanghai 201620, China; 2. China GDE Engineering CO., LTD., Guangzhou 511440, China
Abstract:This work experimentally investigated the size-distribution and concentration changes of indoor bioaerosol before and after ultrasonic humidification via the orthogonal experiment methods in three heated experimental chambers (23℃) to clarify the exposure risk of indoor airborne bacteria and fungi during ultrasonic humidification. Effectiveness of three well-recognized influencing factors, i.e., target relative humidity (RH=40%, 55%, 70%), humidifier water type (distilled water, tap water, cooled boiled water), and window opening degree (0, 1/6, 1/3) on mitigating the exposure risks was also rated according to Range Analysis and Analytical Hierarchy Process (AHP). The results showed a substantial increase of indoor bacterial and fungal aerosol concentrations, by 294% and 798%, respectively, after ultrasonic humidification; the surged microbes were concentrated in the inhalable ranges. The three factors varied in their effectiveness in mitigating the bioaerosol exposure during humidification, which was ranked by AHP as: humidifier water quality (45%)> target relative humidity (44%)>window opening (11%). To minimize the exposure risks, distilled water and a medium humidification level (such as RH=55%) should be prioritized for ultrasonic humidification, while the effect of window opening degrees is relatively insensitive.
陈露安, 杨传钧, 谷雨倩, 刘学虎, 杨自力. 超声波加湿室内微生物气溶胶浓度与优化方法[J]. 中国环境科学, 2022, 42(4): 1594-1600.
CHEN Lu-an, YANG Chuan-jun, GU Yu-qian, LIU Xue-hu, YANG Zi-li. Impacts of ultrasonic humification on size-distribution and concentration variations of indoor bioaerosol and its optimization strategy. CHINA ENVIRONMENTAL SCIENCECE, 2022, 42(4): 1594-1600.
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