Pollution & air quality
Outdoor air quality
Tracking air quality and pollution
Government agencies measure the amount of pollutants in the air and offer air quality reports and forecasts. It’s important for everyone, especially people with lung diseases, to keep track of current air quality levels in their area. If you know pollution levels are high (air quality is bad) you can take steps to protect your breathing.
The federal government also monitors how much pollution is created at different factories and industries (point sources).
The Air Quality Index (AQI) and the Air Quality Health Index (AQHI)
Environment Canada reports on air quality (air pollution levels) using rating scales. These rating scales keep track of what pollutants are affecting an area, and how much of them there are. The rating scales are usually updated several times a week.
Environment Canada now has two ways of measuring smog: the Air Quality Index (AQI) and the Air Quality Health Index (AQHI).
The Air Quality Index (AQI) measures the level of six major air pollutants and gives a reading based on the pollutant that’s at the worst level that day. For example, one day there might be a little ground-level ozone, a little carbon dioxide and a lot of fine particular matter. The Air Quality Index reading for that day would be based only on the level of fine particular matter, because fine particulate matter is the biggest pollutant that day.
The Air Quality Index (AQI) scale ranges from 0 to 100. The lower the AQI number, the better the air quality. For example, if the air quality index is at 25 or less, the air quality is considered good. If the air quality index is 51 to 100, it’s considered poor air quality.
The Air Quality Health Index (AQHI) is a new rating system that helps you understand what the air quality around you means to your health.
The Air Quality Health Index (AQHI) doesn’t just measure one pollutant at a time. Instead, it looks at the levels of a combination of common air pollutants. The Air Quality Health Index takes into account that exposure to many pollutants, even at low levels, can add up and damage your health. For example, on a day that had low levels of three kinds of pollutants, the Air Quality Health Index would take into account all three pollutants and give a reading that reflects all three. The Air Quality Health Index also offers information on how to adjust your daily activities so you’re less likely to be harmed by smog.
The Air Quality Health Index has a scale that goes from 1 (low health risk) to 10 or more (very high health risk). For example, for people most at risk (seniors, children, those with breathing problems), even a low-to-moderate AQHI number may mean that they have to reduce or reschedule activities. For the general population, a high AQHI reading means they should postpone their strenuous outdoor activities until later or do less strenuous activity if they notice any symptoms from smog (coughing, throat irritation).
Right now, the Air Quality Health Index (AQHI) is only available in selected communities across Canada. However, the federal government plans to offer the AQHI readings in major cities across the country by the end of 2011.
How to keep track of the air quality in your area
Although “smog season” is usually April to September, smog can happen at any time in the year. Make it habit to check the air quality index in your area every day. If you know in advance that the air quality will be bad, you can plan your day around it.
There are many places you can find air quality reports and smog forecasts:
- Environment Canada’s air quality forecasts and advisories are one-or two-day predictions of pollution levels. This site also links to current conditions for towns and cities across the country.
- The Weather Network, a for-profit website, offers air quality reports for all provinces except Saskatchewan. This site offers a free service that sends you daily alerts about local air quality.
- Your local daily newspaper, television and radio stations usually offer air quality information in their weather forecasts. Public health units may offer smog advisories on days when the air quality index levels are high.
Government tracking of the sources of pollution (point sources)
Many industrial, commercial and other stationary sources produce emissions that create outdoor air pollution. The following government programs keep track of emissions from many industries and sectors:
National Pollutant Release Inventory from Environment Canada
Clean air online: pollution sources from Environment Canada
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