National Air Pollution Surveillance (NAPS) Program

The National Air Pollution Surveillance (NAPS) Program is Canada’s main source of outdoor air quality data. Established in 1969, the Program now collects and reports ambient air pollution data from almost 280 monitoring stations across Canada. These stations are located in both cities and rural areas. All data are stored in the Canada-Wide Air Quality Database (CWAQD). 

The NAPS Program is managed by Environment and Climate Change Canada (ECCC) in collaboration and cooperation with provincial, territorial, and regional government monitoring networks. NAPS data support a wide range of national and international initiatives, including the Air Quality Health Index (AQHI), the Canadian Environmental Sustainability Indicators (CESI), the World Health Organization (WHO) Air Quality Database and the Canada-United States Air Quality Agreement (AQA). 
 
Data products and information about the NAPS Program are available in the "Data and Resources" section of this page. The ECCC Data Catalogue provides pre-generated air quality data files. The NAPS Data Query Tool allows users to perform custom data searches for select datasets. 

For additional information, please contact the NAPS Inquiry Centre at RNSPA-NAPSINFO@ec.gc.ca.

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 analyzers 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 three or 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 micrometres (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 NAPS 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 for a subset of sites sampled on a time-integrated basis include: 
• particulate composition (e.g., metals, ions), with additional detailed speciation at Tier 1 core sites such as organic and elemental carbon, ammonia and biomass burning markers; 
• 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 for data available at that time. 

Data Disclaimer:

NAPS data are reviewed and updated regularly. The data shown reflect the most current information available in the CWAQD at the time they are published. The types of pollutants measured, as well as how often samples are collected, can differ from one monitoring site to another. 

When data files are updated in the ECCC Data Catalogue, the new version replaces the older one but keeps the same file name and location. The 'DataDonnees’ directory contains continuous and integrated air quality data, organized by sampling year and measurement type, for all data stored in the CWAQD. More details about the NAPS program can be found in the ‘ProgramInformation-InformationProgramme’ folder, with detailed descriptions on recent updates in file ‘NAPS-SNPA_Modification.txt’ 

Citations:

National Air Pollution Surveillance Program, (year accessed). Available from the Government of Canada Open Data Portal at open.canada.ca.

Organization: Environment and Climate Change Canada | Environnement et Changement climatique Canada