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Smog Alert

What is air pollution?

There are many different types of air pollutants from a wide range of sources. The pollutants that most affect health are the gases and particles that contribute to cardiovascular and respiratory disease. These pollutants are often lumped together under the term “smog”.

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Where does smog come from?

The contaminants that create smog are released during the combustion of fossil fuels in our vehicles, power plants, factory boilers and homes. They are also released by industrial processes, the evaporation of liquid fuels and the use of solvents and other volatile products such as oil-based paints. Smog-causing contaminants are released during forest fires, and emitted by natural sources such as: trees, bogs, and volcanic activity. Most of Ontario's smog problems are caused by a combination of local emissions and pollutants carried by the wind from pollution sources in the United States. More than half of our smog problem comes from south of the border.

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How is smog forecast?

The Ministry of the Environment and Climate Change as well as Environment Canada meteorologists combine real-time information on pollutant levels with data on weather patterns, topographical conditions and emission sources to predict the Air Quality Health Index. The data are obtained by a network of 39 air monitoring stations across the province. Over the last four years the ministry has invested more than $6 million in upgrading Ontario's air monitoring network, ensuring accurate and timely data.

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How does smog affect my health and the health of my family?

Depending on the length of time you are exposed, your health status, your genetic background and the concentration of pollutants, air pollution can have a negative effect on your heart and lungs. It can:
Make it harder to breathe
Irritate your lungs and airways
Worsen chronic diseases such as heart disease, chronic bronchitis, emphysema and asthma

Each person reacts differently to air pollution. Children, seniors and those with diabetes, heart or lung disease are most sensitive to the adverse health effects of air pollution.

Negative health effects increase as air pollution worsens. Small increases in air pollution over a short period of time can increase symptoms in those at risk.

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How do I know if I am at risk?

People with diabetes, lung disease (such as chronic bronchitis, asthma, emphysema, lung cancer) or heart disease (such as angina, a history of heart attacks, congestive heart failure, arrhythmia or irregular heartbeat) are more sensitive to air pollution.
Seniors are at higher risk because of weakening of the heart, lungs and immune system and increased likelihood of health problems such as heart and lung disease.
Children are also more vulnerable to air pollution: they have less-developed respiratory and defense systems. Children also spend more time outdoors being physically active, which can increase their exposure to air pollution.
People participating in sports or strenuous work outdoors breathe more deeply and rapidly, allowing more air pollution to enter their lungs. They may experience symptoms like eye, nose or throat irritation, cough or difficulty breathing when air pollution levels are high.

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What is the purpose of Special Air Quality Statements and Smog and Air Health Advisories?

The purpose of these alerts is to inform people with breathing difficulties to avoid unnecessary exposure to smog, to inform major pollution sources that they should consider, if possible, reducing their emissions, and to solicit everyone's help in lessening the problem by curtailing activities that produce smog.

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What is the difference between a Special Air Quality Statement (SAQS) and a Smog and Air Health Advisory (SAHA)?

If a high risk Air Quality Health Index value is forecast to last for 1 to 2 hours, then a Special Air Quality Statement (SAQS) will be issued. The purpose of a Special Air Quality Statement is to be precautionary and to be vigilant of your health as it relates to the Air Quality Health Index.

If the high risk Air Quality Health Index is forecast to be persistent, a duration of at least 3 hours, then a Smog and Air Health Advisory (SAHA) will be issued.

Both Special Air Quality Statements and Smog and Air Health Advisories are issued jointly by Environment Canada and the Ontario Ministry of the Environment and Climate Change.

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What should I do if a Special Air Quality Statement or Smog and Air Health Advisory is called?

Here are some actions you can take to help protect the environment and your own health:

At home:

  • Conserve electricity year-round by adjusting the heat or air conditioner and turning off lights you are not using.
  • Avoid letting your car, or any other engine, idle for long periods.
  • Reduce your use of gasoline-powered equipment.
  • Avoid mowing the lawn when air quality is poor.
  • Don't use oil-based products such as paints, solvents or cleaners if you can avoid them. They contain volatile organic compounds (VOCs), which contribute to smog.
  • Avoid or reduce strenuous physical outdoor activities when smog levels are high, especially during the late afternoon. Do not exert yourself outdoors.
  • If possible, stay indoors in a cool, air-conditioned environment.
  • Get engine tune-ups and car maintenance checks as advised by the car manufacturer's maintenance schedule.
  • Limit the amount of wood you burn in your fireplace or woodstove. When burning wood, use only the dry, seasoned variety.

At work:

  • If possible, take public transit, or walk to work.
  • If you use a car, don't travel alone; encourage and facilitate carpooling.
  • Avoid traffic congestion.
  • Consider teleconferencing, instead of traveling to meetings.

As always, consult your doctor for specific medical advice on how to cope with poor air quality.

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Halton Smog and Air Health Advisories to Date

  Total # of Smog Alerts Total # of Days
0 0

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