May 29, 2006
Media Release

Smog advisory issued for York Region

NEWMARKET A smog advisory has been issued by the Ontario Ministry of the Environment (MOE) for various areas, including York Region. The advisory remains in effect until further notice.
A Smog Advisory means that there is a strong likelihood that there may be poor air quality within the next 24 hours due to ground-level ozone and/or fine particulate matter. York Region Health Services offers residents the following information and advice to protect themselves and their families from the harmful effects of exposure to smog.
Smog is a combination of airborne pollutants that affect our health and our natural environment. Most harmful are ground-level ozone and fine airborne particles that, once inhaled, can introduce harmful mixtures of chemical compounds into our lungs.
Smog most often occurs on hot, humid summer days. Ground level ozone forms when nitrogen oxides and volatile organic compounds react together in the presence of intense sunlight. Smog levels are influenced by factors such as weather systems and airflow patterns. High levels of smog are often removed after a heavy rainfall.
In some people, even mild exposure to ground level ozone can cause eye, nose and throat irritations, coughing, wheezing and shortness of breath. Smog can lower resistance to infection and can cause illness in people with heart and lung conditions. Those at particular risk include young children, the elderly, asthmatics and anyone with existing respiratory or coronary conditions.
Smog levels are monitored by the Ontario Ministry of the Environment and reported through the Air Quality Index (AQI) program. The MOE conducts hourly readings of the most common air pollutants year-round at 38 sites province-wide and provides as many as six public reports per day from May to September.
The AQI is a rating scale that measures outdoor air quality in Ontario. The AQI translates pollutant levels into numbers to determine whether the air quality is considered to be "good," "moderate" or "poor." The lower the AQI reading, the cleaner the air. A Smog Alert is declared if forecasts indicate the AQI may exceed a reading of 50 in a given geographic area.
The MOE issues two kinds of Smog Alerts. A "smog watch" indicates a 50% chance that poor air quality will occur within the next three days. A "smog advisory" is issued when there is a high probability that poor air quality is occurring or may occur within the next 24 hours due to ground-level ozone and/or fine particulate matter. 
During a Smog Alert, the public is advised to take precautions to minimize exposure to air pollutants and to refrain from activities that could worsen air quality. The following is suggested
to protect those most affected by smog:
 Avoid strenuous exercise and limit outdoor activities
 Reschedule outdoor activities until the smog advisory has been cancelled
 Keep away from high traffic areas to reduce exposure to vehicle exhaus
 Stay inside in a cool or well-ventilated environment
 Drink plenty of fluids to prevent dehydration
 Seek medical attention for those complaining of symptoms such as tightness in their chests, coughing, wheezing or shortness of breath, excessive weakness or fatigue
Individuals and businesses can make a big difference in helping to reduce smog levels, including:
 Limit the use of cars: walk, cycle, carpool or take public transit
 Telecommute (work from home) and teleconference whenever possible
 Turn off your vehicle engine if you are stopping for more than 10 seconds, except in traffic.  Idling for more than 10 seconds uses more fuel than restarting your engine.
 Restrict the use of oil-based paints, solvents, pesticides, glues, gas-powered engines (such as lawnmowers and leaf blowers) and barbecues
 Conserve energy: turn down the air conditioner and turn off lights you are not using. Use energy efficient compact fluorescent light bulbs. Install low-flow showerheads and aerators in faucets to conserve water
 Order your own free 20/20 The Way to Clean Air Planner Guide, filled with tips to reduce your energy use, by contacting the Clean Air Partnership at 1-866-583-2020 or visit
For further information on air quality issues or a copy of the Smog Alerts booklet, contact York Region Health Services Health Connection at 1-800-361-5653 (toll free) or visit
To find out what the current Air Quality Index (AQI) readings are for York Region, contact the Ministry of the Environment. The MOE posts air quality reports and 3-day forecasts at Residents can be directly notified of Smog Alerts by registering for the Smog Alert by Email service on the provincial website. Air quality reports are also available by calling 416-246-0411 or 1-800-387-7768.
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For more information on the Regional Municipality of York and our services, please visit
Media Contact: Jennifer Mitchell-Emmerson, York Region Health Services
 Phone:  (905) 830-4444, ext. 4016 or after-hours pager (905) 830-3302


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