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This article was originally written on July 8, 2015, in response to air quality issues in the greater Vancouver district because of many wildfires which were burning in the province of British Columbia. I have updated it today (July 7, 2017) because, once again, the province of British Columbia is having Air Quality Warnings.
When people come to my fitness class, they are concerned about their respiratory health while exercising and there is a debate between participants about opening or closing the windows and/or making use of the community centre's air conditioning system instead of opening the windows.
In the end, the decision is personal — based on your own health issues — as well as gaining some knowledge about air quality, air conditioning, and the health effects of poor air quality.
How is Air Quality determined?
The Province of British Columbia uses a number of methods to measure air quality. Monitoring stations measure the presence of the following contaminants:
- carbon monoxide (CO)
- nitrogen dioxide (NO2)
- ozone (O3)
- particulate matter (PM2.5 and PM10)
- sulphur dioxide (SO2), and
- hydrogen sulphide (H2S).
Contaminants are measured either through continuous or noncontinuous monitoring. In continuous monitoring, air is constantly measured and the data is automatically transmitted to a central database. In noncontinuous monitoring, contaminants collect on a filter over a specified period of time (such as one, three or six days).
The Air Quality Health Index ranges from 1-10. For each category there are suggestions for what the at-risk and general populations should do. They are as follows:
- 1-3: Both at-risk and general populations can enjoy their usual outdoor activities.
- 4-6: At-risk populations should consider reducing activities if they are experiencing symptoms, while the general population should be able to continue their usual activities.
- 7-10: At-risk populations should slow down and do less; general population should consider reducing or rescheduling outdoor activities.
- Above 10: At-risk populations should avoid strenuous activities and avoid physical exertion; the general population should reduce or reschedule strenuous activities outdoors, especially if you experience symptoms such as coughing and throat irritation.
On Sunday, July 5, 2015, Environment Canada listed the Metro Vancouver Air Quality Health Index at a 10+, or “Very High Risk” and on Monday morning downgraded the index to 8 or “high risk”. By Tuesday morning, it had gone down to 2 for metro Vancouver. The air quality for July 8, 2015 was at 4 and was expected to go to 5 the next day. It is likely that Vancouverites will have to pay attention to air quality advisories in future summers.
What causes air pollution?
Air quality is degraded when unwanted chemicals or other materials are released into the air in large enough amounts. The quality of the air depends on the amount of pollutants, the rate at which they are released from various sources, and how quickly the pollutants disperse (or, conversely, how long they are trapped in an area).
Many air pollutants occur as gases or vapours, but some are very tiny solid particles, such as dust, smoke or soot. Some are emitted from natural sources, such as volcanoes, while many others come from human activity. This is what we are experiencing in Vancouver — many forest fires burning in the province and very little wind to move the smoke.
When does Air Quality cause Health Issues during Exercise?
Here are the answers to that question from Edward R. Laskowski, M.D.
"While aerobic activity is one of the keys to a healthy lifestyle, air pollution and exercise can be an unhealthy combination. This is especially true if you have asthma, heart or lung conditions, or lower respiratory disease.
"Even when you're not exercising, exposure to air pollution can cause health problems. But with the combination of air pollution and exercise, the potential health problems are increased.
"One reason for this increased risk may be that during aerobic activity, you usually inhale more air and breathe it more deeply into your lungs. And because you're likely to breathe mostly through your mouth during exercise, the air you breathe in generally bypasses your nasal passages, which normally filter airborne pollution particles."
There is no doubt that air pollution can cause health problems. Some of the more common are:
- Damage to airways of the lungs;
- Increased risk of asthma development;
- Worsening of existing asthma or other lung conditions;
- Increased risk of heart attacks and strokes; and,
- Increased risk of death from lung cancer and cardiovascular disease.
What's not clear with air pollution and exercise is how much exposure is a danger, or how long you have to be exposed.
While exercise has clear health benefits, when air quality is poor, each individual has to decide how much risk they wish to take. Each individual needs to focus on ways to minimize the risks of the air pollution while exercising.
What changes should be made, if any, to your exercise routine when the air quality is poor?
There are things you can do to limit the effects of air pollution and exercise. They include:
- Monitor air pollution levels. British Columbia has an Air Quality site which gives readings by area and by day.
- Avoid outdoor physical activity or reduce the intensity and duration of your outdoor exercise when an air quality alert has been issued.
- Also avoid outdoor activity when pollution levels tend to be highest, which is often midday or afternoon.
- Avoid high-pollution areas (this could be within 50 feet of a road or near an outdoor smoking area).
- Exercise indoors. Take a fitness class, check out a local gym or run laps on an indoor track.
- If you have any upper respiratory condition, such as asthma or COPD, check with your doctor about when it's safe for you to exercise.
What about air conditioning? Is it safe to exercise in an air conditioned room?
The West End Community Centre does have an air conditioning system and, during hot weather spells, they are labelled as a "cooling centre" by the city.
Air conditioners and refrigerators work the same way. Instead of cooling just the small, insulated space inside of a refrigerator, an air conditioner cools a larger area. They use chemicals that easily convert from a gas to a liquid and back again. This chemical is used to transfer heat from the air inside an area to the outside air.
Air conditioners, if made well and serviced frequently, should not release dangerous chemicals into the air — either inside or outside the building. But they sometimes do. The chemical they release is called Hydrochlorofluorocarbons (HCFC's) and they do pollute the air.
HCFCs are mainly used for foam blowing, refrigeration and air conditioning, solvent cleaning and to a lesser extent, aerosols and fire protection. At the 19th Meeting of the Montreal Protocol, it was agreed to accelerate the phase-out of HCFCs in both developed and developing countries.
Most air conditioners today are much better made than those made twenty years ago. If the air conditioner is made properly and maintained efficiently, you should not be breathing any pollutants while inside a building that is air conditioned.
During poor Air Quality warnings, should we exercise?
It's definitely not wise to exercise outdoors during high air quality warnings. But exercising indoors is possible, particularly if you do not suffer from any specific breathing or upper respiratory conditions.
Ultimately, it must be a personal decision. Everyone needs to be aware of the Air Quality advisories, as well as their own health issues, and choose accordingly.
I am a BCRPA-certified fitness instructor in Vancouver, BC. I teach four classes at the West End Community Centre in Vancouver, BC, mostly designed for the older adult. The Inevitable Disclaimer: Everything published here expresses only my opinion, based on my training and research. What you do with the information is entirely your own responsibility. I am not liable for any injury you suffer that seems to be related to anything you read here. Always consult your doctor before beginning an exercise program. For other articles, return to the table of contents.
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