Topic B8: IAQ in developing countries MONITORING OF PM 2.5 ARISING FROM DIFFERENT COOKING FUELS IN RURAL RESIDENTIAL HOUSES Zulfiqar ALI 1 , Humaira AMANAT 1 , Safdar SIDRA 1 , Zaheer A NASIR 2 and Ian COLBECK 3 1 Department of Zoology, University of the Punjab, Lahore 2 Healthy Infrastructure Research Centre, Department of Civil, Environmental & Geomatic Engineering, University College London, London WC1E 6BT, UK 3 School of Biological Sciences, University of Essex, Colchester, Essex, CO4 3SQ, UK *Corresponding email: dralizulfiqar@gmail.com Keywords: Pakistan, PM 2.5 , Cooking fuels SUMMARY Introduction: Use of biomass as a fuel increases the levels of indoor air pollution. This results in more than 1.5 million deaths per year with the majority being mothers and young children who spend most of their time indoors. Analysis of particulate matter (PM 2.5 ) in rural residential houses has not yet been studied comprehensively in Pakistan. This research was conducted to monitor the concentration of particulate matter in rural houses of the district Kasur, Pakistan. Methods: Three houses were selected from the village on the basis of cooking fuel in use i.e. wood and LPG. Two DustTrak aerosol monitors (TSI Model 8520) were run in parallel for 48 hours in the kitchens and living rooms of the study sites to monitor the levels of PM 2.5 . Ventilation measurements were made using the tracer gas method employing CO 2 as the tracer gas. Results: The average concentration of PM 2.5 in the three kitchens was 466 μg/m 3 , 845 μg/m 3 and 262 μg/m 3 whereas the average levels of PM 2.5 in the living rooms were 443 μg/m 3 , 1121 μg/m 3 and 416 μg/m 3 respectively. Occupant activities along with smoking and cooking were observed to be important contributing factors towards the concentration of particulate matter in the houses. The concentrations of fine particulate matter from wood burning were twice that from LPG. Moreover infiltration between the kitchen and living room also affected the indoor air quality of both micro-environments. Conclusions: The PM 2.5 levels in houses using LPG were 10 to 18 times higher than the WHO limit while in the house burning wood; the levels were 34 to 45 times higher. The elevated levels of PM 2.5 pose a serious health threat and steps must be taken to reduce the use of biomass as fuel. INTRODUCTION Air is essential to the life of humans, animals and plants. However, this air has never been completely pure; it has always contained materials from natural and anthropogenic sources (Boubel et al., 1994). Particulate matter can be defined as any substance that exist as a liquid or solid in the atmosphere under normal conditions and generally ranges in size from 0.1 to 50