Overview
Although Canada’s National Ambient Air Quality Objectives (NAAQOs) were established in the 1970s and remain in effect, the job of regulating air pollutants in Canada is shared between the NAAQOs and the Canada-Wide Standards, which were meant to harmonize standards between regions. Pollutant standards are usually delegated to one policy or the other.
National ambient air quality standards and objectives
Regulating Body
Environment and Climate Change Canada and the Canadian Council of Ministers of the Environment
Nationwide
History
Canada currently uses two sets of air quality standards: National Ambient Air Quality Objectives (NAAQOs) and Canada-Wide Standards (CWS).
The first National Ambient Air Quality Objectives (NAAQOs) were created in the mid-70s, and are supported by Canada’s foremost federal environmental law, the Canadian Environmental Protection Act (CEPA).
In 1998, an alternative regulatory tool was adopted to help manage environmental issues within Canada. Canadian Environment Ministers (except Quebec) signed the Canada-Wide Accord on Environmental Harmonization, putting into effect a set of standards known as the Canada-Wide Standards (CWS). Under the CEPA 1999, CWS are considered Environmental Quality Objectives. In June 2000, CWS for PM and O3 were assigned, committing the nation (except Quebec) to significant reductions in PM and ground-level ozone by 2010.
Air pollutants recognized as problematic are either managed through the NAAQOs program or the CWS, not both. Some departments in the Canadian government, however, have integrated their NAAQOs and CWS divisions.
Technical Standards
| Pollutant | Averaging Time | Maximum Desirable Level | Maximum Acceptable Level | Maximum Tolerable Level |
|---|---|---|---|---|
| Sulphur dioxide (SO2) | annual 24 hours 1 hour |
11 ppb 57 ppb 172 ppb |
23 ppb 115 ppb 334 ppb |
— 306 ppb — |
| Total Suspended Particulate (TSP) | annual 24 hours |
60 µg/m3 — |
70 µg/m3 120 µg/m3 |
— 400 µg/m3 |
| Carbon Monoxide (CO) | 8 hours 1 hour |
5 ppm 13 ppm |
13 ppm 31 ppm |
17 ppm — |
| Nitrogen Dioxide (NO2) | annual 24 hours 1 hour |
32 ppb — — |
53 ppb 106 ppb 213 ppb |
— 160 ppb 532 ppb |
| Ozone (O3) | annual 24 hours 1 hour |
— 15 ppb 51 ppb |
15 ppb 25 ppb 82 ppb |
— — 153 ppb |
