title: Effect of Ventilation on Occupational Exposure to Airborne Biological Contaminants in an Isolation Room.
abstract: BACKGROUND
  Airborne pathogens play an important role in a hospital air quality. Respiratory infections are the most common occupational disease among the health care staff. The aim of this study was to determine the effect of ventilation system parameters and patient bed arrangements on concentration of airborne pathogens in indoor air of an isolation room.
  
  
  METHODS
  A single-bed room was considered in which a patient diagnosed with tuberculosis had been admitted. Five different ventilation types, each at four different capacities were installed in the room while two different locations for the patient's bed were assessed. A direct-impact sampling method (blood agar plate) was used in order to determine the intensity of the bio-aerosols in indoor air of the isolation room.
  
  
  RESULTS
  The results showed that when the air was supplied through a circular vent located on the northern wall and the vented air was exhausted via a linear vent located on the southern wall, the average concentration of the bio-aerosols in the air, (with 12 air changes per hour) was reduced to 25 colonies per cubic meter (cfu/m(3)) (in the range of 25-88 cfu/m(3) and a 95 percent confidence interval). In accordance with the analysis applied upon the two different locations of the bed, no significant difference was observed (P>0.05).
  
  
  CONCLUSIONS
  Installation of ventilation systems as determined by the study is recommended for tuberculosis isolation rooms.
authors.affiliation: Department of Occupational Health Engineering, Faculty of Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Javad
authors.initials: MJ
authors.lastname: Jafari
authors.affiliation: Department of Occupational Health Engineering, Faculty of Health, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mohammad Reza
authors.initials: MR
authors.lastname: Hajgholami
authors.affiliation: Department of Occupational Health Engineering, Faculty of public Health, Tehran University of Medical Sciences, Tehran, Iran.
authors.forename: Leila
authors.initials: L
authors.lastname: Omidi
authors.affiliation: Department of Pathology, Faculty of Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mina
authors.initials: M
authors.lastname: Jafari
authors.affiliation: Mycobacteriology Research Center, National Research Institute of Tuberculosis and Lung Diseases (NRITLD), Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Payam
authors.initials: P
authors.lastname: Tabarsi
authors.affiliation: Occupational Medicine, Chronic Respiratory Diseases Research Center, NRITLD, Tehran, Iran.
authors.forename: Soussan
authors.initials: S
authors.lastname: Salehpour
authors.affiliation: Biostatistics Department, Faculty of Allied Medical Sciences, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Zohre
authors.initials: Z
authors.lastname: Amiri
keywords: Airborne; Biological; Occupational Exposure; Ventilation