Assessment of Bioaerosols in Public Restrooms

화장실 공기 중 미생물 분포 조사연구

  • Kim, Jong-Gyu (Department of Public Health, Keimyung University) ;
  • Kim, A-Hyeok (Department of Public Health, Keimyung University) ;
  • Kim, Joong-Soon (Department of Industrial and Management Engineering, Keimyung University)
  • 김종규 (계명대학교 공중보건학과) ;
  • 김아혁 (계명대학교 공중보건학과) ;
  • 김중순 (계명대학교 경영공학과)
  • Received : 2014.06.01
  • Accepted : 2014.07.15
  • Published : 2014.08.31


Objectives: This study was performed to examine bioaerosols in indoor air in public restrooms, as well as to assess the effects of air temperature and relative humidity on bioaerosol levels. Methods: A cross-sectional survey was performed in ten male and ten female restrooms. An air sampler (Anderson type) was used for sampling total suspended bacteria (TSB), Gram-negative bacteria (GNB), Gram-positive bacteria (GPB), opportunistic bacteria (OP), Staphylococcus spp., and total suspended fungi (TSF). Results: The levels of TSB were $10-10^2CFU/m^3$ and TSF $10-10^2CFU/m^3$, respectively. The GNB level was $0-10CFU/m^3$, and GPB and OP levels were $10-10^2CFU/m^3$. Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) were detected in 90% of the restrooms. The GPB level was higher in the female restrooms than in the male restrooms (p < 0.05). TSB, GNB, and TSF showed higher levels in restrooms in buildings over 30 years old (p < 0.01). The main effect of air temperature or relative humidity and interaction effect of the two factors on the TSB level were significant (p < 0.05), while the effect of relative humidity on the TSF level was significant (p < 0.001). Conclusions: These results indicate that there is a wide variation in the bioaerosol levels among different restrooms. The observed differences in bioaerosol levels reflect different building histories. The effects of air temperature and/or relative humidity reveal that bioaerosol levels may vary according to season or time of day. Future research is needed to further characterize the relation between the bioaerosol levels and surface contamination in restrooms.


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