Unhealthy air quality according to share of days Singapore 2007-2021
In 2015, 0.5 percent of the days in the year was recorded to be in the unhealthy range. Air quality in 2013 and 2015 was affected by transboundary smoke haze from land and forest fires. Singapore experienced a full-year of good and moderate air quality (in terms of PSI) in the years 2007, 2008, 2018 and 2020.
