The quality of the air that we breathe plays an important role in our health. For years we have known that pollution, smog and other air contaminants can either cause health- related problems, or make pre-existing heart and lung conditions worse. In fact, the Great Smog or Big Smoke of Britain in 1952 was followed by over 10,000 deaths as well as a significant number of people suffering ill effects to their health, mostly respiratory. This is not surprising as one of the ways that harmful chemicals or particles can easily get into our bodies from the air is by breathing them in. For years we have relied on the Air Quality Index (AQI) to be able to guide us. The index was essentially a score or rating. In simple terms, the higher the index, the more harmful is the air. Currently one of the most obvious examples of poor air quality is the smoke and related pollution that is now plaguing large parts of our Western provinces due to the ongoing unprecedented forest fires.
Obviously although poor air quality can ultimately affect anyone depending on the levels, high risk individuals are even more susceptible. Persons that are considered at high risk to suffer from the consequences of poor air quality include:
- People with existing respiratory or cardiovascular conditions
- Young children
- The elderly
- People active outdoors(participating in strenuous outdoor activities results in breathing in deeper and quicker, so more pollution enters the lungs)
Recognizing the vital relationship between health and air quality, Environment Canada in collaboration with provincial partners has now developed a new, more precise risk measure called the Air Quality Health Index (AQHI). The index provides a score or rating between 1(low risk) and 10(very high risk).
According to Environment Canada here is what the various ratings mean:
- AQHI between 1 and 3 is considered low and ideal air quality for both the general at risk populations.
- AQHI between 4 and 6 is considered moderate. Persons at risk should consider reducing or rescheduling strenuous activities outdoors if experiencing symptoms. For the general population, there is no need to modify usual outdoor activities unless they experience symptoms such as coughing and throat irritation.
- AQHI between 7 and 10 is considered high. Persons at risk should avoid strenuous activities outdoors. Children and the elderly should also avoid outdoor physical exertion. People not at risk should consider reducing or rescheduling strenuous activities outdoors if they experience symptoms such as coughing and throat irritation.
- AQHI above 10 is considered very high. Persons at risk should avoid strenuous activities outdoors. Children and the elderly should also avoid outdoor physical exertion. Persons not at risk should reduce or reschedule strenuous activities outdoors, especially if they experience symptoms such as coughing and throat irritation.
You can find out your local AQHI in Canada online at www.weather.gc.ca and click on the Air Quality link.
For US air quality data visit the EPA website.