Air Quality Objectives & Standards

Air quality objectives are non-statutory limits on the acceptable presence of contaminants in the atmosphere, established by government agencies to protect human health and the environment. They are generally expressed in terms of a concentration (e.g., micrograms per cubic metre, or parts per billion) measured over a specific period of time (e.g., one hour, 24 hours or one year).

British Columbia has adopted air quality objectives and standards for a number of contaminants, including: Particulate Matter (PM)10, PM2.5, ozone, sulphur dioxide, nitrogen dioxide and carbon monoxide. 

How Air Quality Objectives are Used

Objectives are one kind of "criteria." Criteria also include standards, guidelines and planning goals. Air quality objectives are used to guide decisions, unless written specifically into a permit or regulation. They are typically used to:

  • assess current or historical air quality;
  • guide decisions on the permitting of new or modified facilities;
  • guide decisions on episode management, such as air quality advisories;
  • develop long-term air-management strategies and evaluate progress, and
  • aid regulatory development.

As even low levels of air pollution can affect some individuals, air quality objectives should not be viewed as levels we can “pollute up to," but levels to stay well below.

Air Quality Objectives Review

The B.C. government is considering approaches to review and establish new provincial air quality objectives (AQO) and reviewing provincial air quality objectives for nitrogen dioxide (NO2).

A discussion paper was prepared to explain of the proposed revisions. Those interested were invited to submit their comments anonymously about the discussion paper contents, between February 28 and March 27, 2019.

Next Steps

In the spring of 2019, a review of all of the comments received will be completed. This will help determine how we will update our process to set air quality objectives. If you have any questions regarding the Air Quality Objectives discussion paper, please contact Natalie Suzuki by e-mail at

Objectives & Standards

For more information, see Provincial Framework for Developing Provincial Air Quality Objectives (PDF).