High indoor particulate matter concentrations in developing countries and the apparent scale of its impact on the global burden of disease underline the importance of particulates as an environmental health risk and a consequent need for their monitoring, particularly in indoor school micro-environments. PM10, PM2.5, and PM1.0 concentrations were monitored inside and outside classrooms in 4 naturally ventilated schools in winter (December 2007 to January 2008) and summer (April to May 2008) seasonal campaigns using Grimm 1.109 along with CO2, temperature, humidity, and ventilation rate. In addition, data on classroom, school building, and surrounding area conditions and prevalence of health symptoms were collected using a questionnaire. In winter, mean indoor PM10, PM2.5, and PM1.0 concentrations were up to 497, 220, and 135 íg/m3, which decreased 3, 3, and 2 times, respectively, in summer versus winter. Average indoor: outdoor ratios were >1 at nearly all sites. Indoor/outdoor correlations indicated poor correlations at all sites except 1 school in a residential area. Inter-particulate ratios in indoor environments indicated strong correlations existed in both campaigns, which were significant at p <0.01.
Authors: Habil, Mahima; Taneja, Ajay ;Full Source: Indoor and Built Environment 2011, 20(4), 430-448 (Eng) ;