Ambient Temperature and the Air Quality Health Index

Abstract

The Air Quality Health Index (AQHI) [1] was introduced in Canada to represent a summary measure of ambient air pollution and air health effects. The AQHI is primarily applied to inform the Canadian public of health risks associated with ambient air pollution. It is used as a scaled indicator of environmental health risk. The AQHI is hourly calculated based on formula using the rolling three-hour average concentration levels of three air pollutants. These are the gases, ozone (O3) at ground level and nitrogen dioxide (NO2), and particulate matter (PM2.5 - particles of air pollutants with a diameter of 2.5 micrometers or less). The formula realized to calculate the index is as follows: AQHI=(100*10/10.4)*(e(0.000537*[O3])+e(0.000487*[ PM2.5]) + e(0.000871*[NO2]) - 3) The AQHI value is defi ned based on the relative risk of mortality associated with these 3 air pollutants. The coeffi cients in the above formula were estimated using relation between acute increases in air pollution and associations with increased risk of death as determined using data from major cities across Canada [1].