Indoor air pollution
While air pollution is often associated with the outdoors, sources of pollution are also present within the home. During Pongsuk’s data collection, PM2.5 was identified while he was at home with his family. This could have been emitted during cooking activities, as combustion releases particulate matter into the air. The disturbance of dust caused by human movement or an open window letting in outdoor pollutants, may have also contributed to this increase.
On one night when Pongsuk was sleeping, indoor pollution levels remained constant at 30 µg/m3 and did not drop. Over this 10-hour period, PM2.5 levels were up to two times higher⁷ than prescribed WHO safe levels⁸. As well-sealed homes can lead to pollutants being trapped indoors and lingering overnight, it is recommended to ventilate the home when the outdoor air quality is good. When outdoor air pollution is high, keeping windows and doors closed while operating an air purifier at home is advised.
Dyson purifier data also revealed up to two times higher⁹ PM2.5 levels indoors during the haze period against the non-haze period. This rise in the overall particulate matter exposure measured in Bangkok homes corresponds with the air quality data recorded using Dyson’s prototype air quality backpack, indicating a shift in the air quality index from ‘good’ in Phase 1 to ‘fair’ in Phase 2.