May 13, 2004

Smog advisory information

NEWMARKET The first smog advisory of the season has been issued by the Ontario Ministry of the Environment for various areas, including York Region. The advisory will remain 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. The Air Quality Index program is managed by the Ministry of the Environment, who issues the information to the public.
As an education measure, York Region Health Services offers residents the following information to become better informed and protected from the harmful effects of exposure to smog.
During the warm weather months, York Region may experience periods of smog that can cause air quality to fall well below acceptable standards. 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. The Air Quality Index (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." Generally, the lower the AQI the better the air quality.
The AQI program is managed by the Ministry of the Environment (MOE). The MOE conducts hourly readings of the most common air pollutants year-round at 36 sites province-wide and provides as many as six public reports per day during May to September. A Smog Alert is
(Smog continued)
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 there may be poor air quality within the next 24 hours due to ground-level ozone and 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 or plan outdoor activities for early in the morning or late in the day when pollutant levels are considerably lower
 Keep away from high traffic areas to reduce exposure to vehicle exhaust
 Stay inside in a cool air-conditioned 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
 Reduce unnecessary engine idling of your vehicle at all times
 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 light bulbs. Install low-flow showerheads and aerators in faucets to conserve water
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).
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 dialing 416-246-0411 or 1-800-387-7768.
For more information on the Regional Municipality of York, the services we offer and links to our nine area municipalities, please visit our website at
Contact:  Wendy Lewis, York Region Corporate Communications Services
   905-830-4444 Ext. 1238


The Regional Municipality of York is committed to providing cost-effective, quality services that respond to the needs of our rapidly growing communities.  York Region is comprised of the following nine area municipalities:  Aurora, East Gwillimbury, Georgina, King, Markham, Newmarket, Richmond Hill, Vaughan and Whitchurch-Stouffville.  For more information, visit our Web site at:

Contact: Patrick Casey, Senior Media Relations Specialist, York Region

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