This research aims to develop indirect measures of indoor and outdoor air pollution, which can be used for computing personal exposure by linking an individual’s time-activity diary with the indirect estimates of indoor and outdoor air pollutions. Building on current research, satellite remote sensing will be used to estimate ambient air pollution at a household location. Imputing indoor air pollution, however, can be challenging. In this research indirect measures of indoor air quality will be identified by evaluating the indoor air pollution with reference to household characteristics, such cooking and heating fuel, flooring type, number of occupants, exchange of air between indoor and outdoor environments and ambient air pollution at the household location. The study will sample indoor and outdoor air quality, measured by fine and coarse particles (PM2.5, PM10, PM10-2.5), in 33 households in and around Iowa City during the fall 2008 and spring 2009. An incremental optimal sampling design will be adopted to draw the sample of households, which will capture more than 95% of the total variability in ambient air pollution. Particulates of different sizes will be monitored for a week in and outside of each household, and a brief questionnaire will be administered to collect the data on household characteristics. The analyses of these data using standard statistical methods will allow us to determine indirect measures of indoor air pollution.