Provincial air quality objectives for PM2.5

PM_2.5, or fine particulate matter, is a key air pollutant in B.C. that poses significant health risks even at low levels. The province has adopted ambient air quality criteria to help guide decisions and protect public health.

PM_2.5, or fine particulates, refers to particles that are 2.5 microns or smaller in diameter. PM_2.5 is one of the most important outdoor air pollutants in B.C. from a human health perspective. New ambient air quality criteria for PM_2.5 were adopted by the Province of B.C. on April 9, 2009. They are nonstatutory limits used to guide air-management decisions in British Columbia.

The 24-hour and annual air-quality objectives (AQOs) are the primary air management tool, used to guide decisions on environmental impact assessments and authorizations, airshed planning efforts and regulatory development. The 24-hour AQO is also used to guide decisions on whether or not to issue an air quality advisory.

The planning goal is intended as a voluntary target to guide airshed planning efforts and encourage communities to maintain good air quality in the face of economic growth and development.

The new provincial criteria for PM_2.5 are in addition to the existing provincial AQO of 50 µg/m3 (24-hour average) for PM₁₀ (i.e., fine particles 10 micrometres or smaller).

• Provincial Framework for Developing Provincial Air Quality Objectives (PDF, 192.2KB)

Canadian ambient air quality standards for PM_2.5

In 2025, new national standards for PM_2.5 were endorsed by the Canadian Council of Ministers of the Environment. The new Canadian Ambient Air Quality Standards (CAAQS) for PM_2.5 has a 2030 implementation date, at which point it will replace the current 2020 standard. In B.C., CAAQS for PM_2.5 are used for air zone reporting, to drive airshed management, and as reference for the adoption of any provincial Air Quality Objectives (AQO) following the framework of AQO adoption.