this study, density and type of bioaerosols in the indoor-air are studied in Imam Sajjad Hospital, Yasuj.

Abstract: The effect of polluted air on human health and survival is undeniable. Bioaerosols in the breathing air, can affect human health in different ways. Bioaerosol are particles transported by air and include bacteria, fungi, viruses and other substances. Bioaerosols may cause nosocomial infections that affect all hygienic, economic and social aspects of the individuals. Given that hospital infections are associated with the type and concentration of bioaerosols, thus in this study, density and type of bioaerosols in the indoor-air are studied in Imam Sajjad Hospital, Yasuj.   Materials and Methods: This study is a descriptive and cross-sectional study conducted in four wards of Imam Sajjad Hospital in Yasuj. 240 samples using the instruction NIOSHA by Anderson with a flow of 28/3 L / min for 2 minutes during four months were collected and examined. The culture medium was   tryptic agar and dextrose agar. samples were kept for 48 h in incubator in 30 ° temperature for bacterial culture and    70 h to 120h in incubator for fungi were incubated at 25-27 degrees. Then the concentration rates were reported based on CFU/ m3  for each bioaerosols.     Findings: The maximum rate of bacterial contamination, observed in the post- partum ward with the amount of 531.14 CFU/ m3 and the minimum rate of the contamination detected for fungal bioaerosols at the post- partum with the amount of 114.47  CFU/ m3  .  The average of total arerosols contamination for bacterial and fungal bioaerosols for all 4 studied wards were 125.78 and 24 CFU/m3 respectively, which can be well observed that fungal bioaerosols average showed lower than the bacterial bioaerosols. According to the results, there has been a significant relationship between concentration of bioaerosols and temperature variables, number of patients in the room during the week. The value of different bacteria were (% 76 / 57) for Aureus, (% 79/36) for Bacillus, Nocardia (% 23/4), Micrococcus (68% / 0), Streptococcus (38% / 0), Corynebacterium (% 12/0) and enterococci (04% / 0). The range of highest to  lowest amount  of fungi found in hospitals were Rhizopus% (71/39), Penicillium (% 47/32), yeast (57% / 18), Alternaria (% 69/3), ... and Traycco Faygom (% 23/0), respectively.   Conclusion: Based on obtained results, the concentration of bioaerosols in various wards of hospital was higher than the standard range and WHO guidelines. Therefore, according to this results, proper ventilation, air purification, people entry restricting, using absorbents, temperature and humidity control have been recommended due to suppling indoor air in the good quality in different parts of the hospital.