Tehran University of Medical Sciences Journal of Air Pollution and Health 2476-3071 1 3 2016 09 04 215 218 EN Faramarz Azimi Ph.D Candidate, Environmental Health Engineering Department, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Ramin Nabizadeh Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran Mahmood Alimohammadi Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran Kazem Naddafi Department of Environmental Health Engineering, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran AND Center for Air Pollution Research (CAPR), Institute for Environmental Research (IER), Tehran University of Medical Sciences, Tehran, Iran 2016 06 16 2016 08 21 Introduction: Maintenance of adequate hospital indoor air quality (HIAQ) in operating rooms (ORs) is critical to the Surgical Site Infection (SSI) in hospitalized patients. This study assessed the concentration of bacterial bioaerosols in various ORs in a hospital. Materials and methods: The concentration of bacterial bioaerosols was measured in the 8 ORs and 2 nurse stations. Active sampling method was used to monitor bacterial bioaerosols. Results: The mean concentrations of the total bacteria were 211-386 and 208-443 CFU/ m3 in the first and second floor, respectively. Gram-positive bacteria (e.g., Micrococcus spp., Staphylococcus spp. and streptococcus spp.) were frequently observed in the assessed ORs and nurse stations. Conclusions: Bacterial bioaerosol monitoring is a useful tool for evaluation of the bio-contamination of ORs in order to improve indoor air quality of them. https://japh.tums.ac.ir/index.php/japh/article/view/53 https://japh.tums.ac.ir/index.php/japh/article/download/53/31