National Air Pollution Surveillance (NAPS) Program

The National Air Pollution Surveillance (NAPS) program is the main source of ambient air quality data in Canada. The NAPS program, which began in 1969, is now comprised of nearly 260 stations in 150 rural and urban communities reporting to the Canada-Wide Air Quality Database (CWAQD). Managed by Environment and Climate Change Canada (ECCC) in collaboration with provincial, territorial, and regional government networks, the NAPS program forms an integral component of various diverse initiatives; including the Air Quality Health Index (AQHI), Canadian Environmental Sustainability Indicators (CESI), and the US-Canada Air Quality Agreement.

Once per year, typically autumn, the Continuous data set for the previous year is reported on ECCC Data Mart.

Beginning in March of 2020 the impact of the COVID-19 pandemic on NAPS Operations has resulted in reduced data availability for some sites and parameters.

For additional information on NAPS data products contact the NAPS inquiry centre at RNSPA-NAPSINFO@ec.gc.ca

Last updated March 2023.

Supplemental Information Monitoring Program Overview

The NAPS program is comprised of both continuous and (time-) integrated measurements of key air pollutants. Continuous data are collected using gas and particulate monitors, with data reported every hour of the year, and are available as hourly concentrations or annual averages. Integrated samples, collected at select sites, are analyzed at the NAPS laboratory in Ottawa for additional pollutants, and are typically collected for a 24 hour period once every six days, on various sampling media such as filters, canisters, and cartridges.

Continuous Monitoring

Air pollutants monitored continuously include the following chemical species:

• carbon monoxide (CO)

• nitrogen dioxide (NO2)

• nitric oxide (NO)

• nitrogen oxides (NOX)

• ozone (O3)

• sulphur dioxide (SO2)

• particulate matter less than or equal to 2.5 (PM2.5) and 10 micrometres (PM10)

Each provincial, territorial, and regional government monitoring network is responsible for collecting continuous data within their jurisdiction and ensuring that the data are quality-assured as specified in the Ambient Air Monitoring and Quality Assurance/Quality Control Guidelines. The hourly air pollutant concentrations are reported as hour-ending averages in local standard time with no adjustment for daylight savings time. These datasets are posted on an annual basis.

Integrated Monitoring

Categories of chemical species sampled on a time-integrated basis include:

• fine (PM2.5) and coarse (PM10-2.5) particulate composition (e.g., metals, ions), and additional detailed chemistry provided through a subset of sites by the NAPS PM2.5 speciation program;

• semi-volatile organic compounds (e.g., polycyclic aromatic hydrocarbons such as benzo[a]pyrene);

• volatile organic compounds (e. g., benzene)

The 24-hour air pollutant samples are collected from midnight to midnight. These datasets are generally posted on a quarterly basis.

Data Disclaimer

NAPS data products are subject to change on an ongoing basis, and reflect the most up-to-date and accurate information available. New versions of files will replace older ones, while retaining the same location and filename. The ‘Data-Donnees’ directory contains continuous and integrated data sorted by sampling year and then measurement. Pollutants measured, sampling duration and sampling frequency may vary by site location. Additional program details can be found at ‘ProgramInformation-InformationProgramme’ also in the data resources section.

Citations

National Air Pollution Surveillance Program, (year accessed). Available from the Government of Canada Open Data Portal at open.canada.ca.