Relationship between the Particulate Matter Concentrations in the Indoor and Ambient Air of the Tehran Children Hospital in 2007

Background and Objectives: In recent years exposure to fine airborne particles has been identified as an important factor affecting human health. Epidemiological studies have showed that the aerosol laden air can be an agent for microorganisms’ dispersion. Ignoring internal sources, ambient air quality significantly affects indoor air quality. Since people spend most of their times in the indoor spaces and little data are available on the general understanding of the indoor air quality, therefore, the aim of this study is to determine the particulate matter concentrations in indoor and ambient air of Tehran Children Medical Center Hospital. Materials and Method: PM10/PM2.5 samples were collected in the indoor environment of the Tehran Children Medical Center Hospital and its adjacent outdoor environment by a portable GRIMM dust monitor model 1.108 from November 26 to March 10, 2007. The places of sampling for indoor and ambient air were in the patient room and the roof of the hospital respectively. Results: The results showed that indoor PM10 level was higher than WHO standards in 80% cases in patient room, whereas, for indoor PM2.5 level, this value was 42 and 64% more than the EPA standards and WHO standards respectively. The relationship between outdoor and indoor particulate matters was examined by linear regression analysis. The indoor particulate matter levels were correlated with the corresponding ambient air ones. Conclusion: Our analysis revealed that infiltration of ambient air could substantially increased indoor pollutants and thereby influences the indoor air quality.