  Indoor air pollution, a significant driver of respiratory and cardiovascular
diseases, claims 3.2 million lives yearly, according to the World Health
Organization, highlighting the pressing need to address this global crisis. In
contrast to unconstrained outdoor environments, room structures, floor plans,
ventilation systems, and occupant activities all impact the accumulation and
spread of pollutants. Yet, comprehensive in-the-wild empirical studies
exploring these unique indoor air pollution patterns and scope are lacking. To
address this, we conducted a three-month-long field study involving over 28
indoor spaces to delve into the complexities of indoor air pollution. Our study
was conducted using our custom-built DALTON air quality sensor and monitoring
system, an innovative IoT air quality monitoring solution that considers cost,
sensor type, accuracy, network connectivity, power, and usability. Our study
also revealed that conventional measures, such as the Indoor Air Quality Index
(IAQI), don't fully capture complex indoor air quality dynamics. Hence, we
proposed the Healthy Home Index (HHI), a new metric considering the context and
household activities, offering a more comprehensive understanding of indoor air
quality. Our findings suggest that HHI provides a more accurate air quality
assessment, underscoring the potential for wide-scale deployment of our indoor
air quality monitoring platform.
