First, our study demonstrated the utility and usability of consumer-grade air quality sensors. The use of such sensors allowed us to monitor air quality levels in individual apartments real-time for several months. This study would not have been possible with more expensive equipment. Our findings show that air pollution levels indoors were affected not only by outdoor pollutant levels and outdoor temperatures but also by building conditions and individual behaviors of seniors, including their ability to use of air conditioners due to cost concerns. A more detailed analysis of data for the entire summer season and all participating apartments will quantify the effect of behaviors inside each apartment on indoor pollution levels, including the effect of individual actions, such as the use of windows, cooking, smoking and/or use of incense.