National Air Pollution Surveillance Program

The goal of the National Air Pollution Surveillance (NAPS) program is to provide accurate and long-term air quality data of a uniform standard across Canada. NAPS was established in 1969 to monitor and assess the quality of ambient (outdoor) air in the populated regions of Canada. NAPS is managed using a cooperative agreement among the provinces, territories and some municipal governments. In 1969, eight provinces -- Nova Scotia, New Brunswick, Quebec, Ontario, Manitoba, Saskatchewan, Alberta and British Columbia -- joined the program. In the first annual data report 36 monitoring sites reported to the Canada-wide database. Today there are 286 sites in 203 communities located in every province and territory.

Measuring air pollutants

NAPS produced its first annual summary in 1972, reporting on measurements of sulphur dioxide and particulate matter. Today sulphur dioxide, nitrogen dioxide, ozone, fine particulate matter and carbon monoxide are continuously monitored. These measurements are used by the provinces to report the Air Quality Index (AQI) and by Environment Canada to report the Air Quality Health Index (AQHI).

Technological advances

The methods used by NAPS to measure air quality have evolved over the years. Additional measurements of a variety of new substances were initiated in the 1980s. Air samples for the additional substances are collected at regular frequencies by NAPS for later analysis at Environment Canada chemistry labs in Ottawa. Various techniques are used to analyze these samples for more than 340 types of chemicals at typical urban NAPS sites. For example, air collected in canisters is analyzed for more than 167 volatile organic compounds that contribute to smog formation. These compounds, such as benzene, are released into the air by motor vehicles, industrial processes and fuel-handling operations. Filter media and foam plugs are used to collect air samples that are analyzed for chemical contaminants that are harmful to human health and the environment.

Providing essential data

NAPS plays an important role in the monitoring and assessment of Canadian ambient air.

Air quality trends

With a continuous dataset from the 1970s to today, NAPS data can be used to assess air quality trends to see if air quality is improving or deteriorating. The data are also interpreted to determine the effectiveness of regulations designed to reduce air pollution.

Air quality impacts

NAPS collects air quality data to share with researchers, regulators and policy-makers in order to assess the impacts of air quality on health and the environment. For example, municipal planners use the data for environmental assessment studies. Researchers at Health Canada and universities also use the data to study the impacts of air quality on human health.

Air quality strategies and programs

The information gathered by NAPS supports strategies to reduce air emissions and manage air quality, such as the Canada-wide Standards for Particulate Matter and Ozone, and the Canada-US Air Quality Agreement. The data provided by NAPS also support public information tools, such as the AQHI and the Canadian Environmental Sustainability Indicators.

Monitoring air quality

Has air quality improved since NAPS first started measuring levels of air pollutants in 1970? The answer is decidedly yes.

Since 1970 lead concentrations have decreased by 97%.

Sulphur dioxide levels have decreased by 96% since 1970.

From 1970 to 2008 particulate matter has decreased by over 50% in ambient air.

Volatile organic compounds, including benzene, have declined significantly since measurements started in 1990.

These trends all suggest that air quality has improved.