Effect of Relative Humidity on Resuspended Particles Caused by Human Walking

doi:10.1007/s12204-020-2176-1

Abstract

Abstract: The goal of this study is to investigate the effects of relative humidity on particle resuspension. The experimental study on the resuspension of different size particles is performed in the laboratory at 50%, 60%, 70% and 80% relative humidity separately. The material of flooring is shaggy carpet. The experiments are carried out in a closed room with four laser dust instruments and a laser dust particle counter. The results show that when the relative humidity is 60% and 70%, the resuspension of indoor particulate matter is likely to occur. Human walking has a greater impact on larger-size particles. Under the conditions of different humidity, four situations all follow a rule that the larger the particle size is, the more stable the particle state is.

Key words: particulate matter| resuspension| relative humidity| suspension rate| human walking

摘要： The goal of this study is to investigate the effects of relative humidity on particle resuspension. The experimental study on the resuspension of different size particles is performed in the laboratory at 50%, 60%, 70% and 80% relative humidity separately. The material of flooring is shaggy carpet. The experiments are carried out in a closed room with four laser dust instruments and a laser dust particle counter. The results show that when the relative humidity is 60% and 70%, the resuspension of indoor particulate matter is likely to occur. Human walking has a greater impact on larger-size particles. Under the conditions of different humidity, four situations all follow a rule that the larger the particle size is, the more stable the particle state is.

关键词: particulate matter| resuspension| relative humidity| suspension rate| human walking

CLC Number:

TU 834.6

ZHENG Shuihua, DU Weiyuan, ZHAO Lipan, LI Xiangpeng . Effect of Relative Humidity on Resuspended Particles Caused by Human Walking[J]. Journal of Shanghai Jiao Tong University (Science), 2020, 25(3): 365-371.

References

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