How is the AQHI calculated and reported?

AQHIs are calculated based on the cumulative health risk attributable to the 3-hour moving average concentrations of four air pollutants namely, ozone (O₃), nitrogen dioxide (NO₂), sulphur dioxide (SO₂) and particulate matter (PM_2.5/ PM₁₀). The risk factors of each pollutant were obtained from local health studies.