Technical information

Contacts

Criteria for issuing a smog warning

A smog warning may be issued when the ground-level ozone concentrations are expected to reach or exceed 82 parts per billion (ppb) and/or concentration of fine particulate matter reach or exceed 35 ug/m3 the next day, or when actual air quality indicate the presence of smog.

Issuing a warning

Weather conditions conducive to formation or accumulation of high ozone concentrations are :

warm air mass;
conditions promoting stagnation, light winds;
long range transport of ozone precursors;
proper synoptic pattern.

The meteorologist on duty at Environment Canada analyses the weather maps and air quality data, then examines the numerical model outputs. If he concludes that the ozone concentrations will reach or exceed 82 ppb at least at one measurement site during 3 hours in the next 24 hours and/or fine particulate matter will reach or exceed 35µg/m3, then Environment Canada issues a smog warning. The bulletins will be transmitted immediately to the Info-Smog partners (PHDs, the Ministère du Développement durable, de l'Environnement et des Parcs and the City of Montréal).

Smog warnings will be issued between 2 PM and 5 PM EDT for the next day, so as to give the public the necessary time to react.

However, if no smog warning has been issued according to the preceeding procedure, a warning may be issued at any time to notify the public if the following conditions are met :

The ozone concentrations are expected to be equal or greater than 82 ppb at least at one measurement site and are expected to persist for at least 3 hours;
The fine paticulate matter are expected to be equal or greater than 35 µg/m3 at least at one measurement site and are expected to persist for at least 3 hours.

Update to a warning

An update to a smog warning already in effect will be issued if Environment Canada expects that weather conditions leading to smog will persist for the next few hours. The update will be issued between 4H00 and 5H30 AM the next day, then between 2H00 and 5H00 PM.

End of warning

An end of warning bulletin is issued when Environment Canada expects that the weather conditions are no longer conducive to ozone concentrations equal or above 82 ppb and that no sampling sites are reporting ozone concentrations above 75 ppb or fine particulate matter concentrations equal or above 30µg/m3.

Info-smog messages

Exemple of smog warning bulletin

Smog warning issued jointly by the City of Montréal Environment Service, the Ministry of Health and Social services of Québec, the Ministère du Développement durable, de l'Environnement et des Parcs, Environment Canada at 16:00 EDT on 27/07/2003.

Through 28/07/2003, weather conditions will be favorable to the deterioration in air quality across the above regions. These conditions will cause a high pollutant build up which is responsible for smog.

The health of the general public should not be significantly affected. More vulnerable individuals, however, such as children, the elderly and people with respiratory or heart ailments may be affected and should reduce outdoor physical activity.

For information on specific health issues, contact the Info-Santé service of your local CLSC community service centre.

On a daily basis, the combined efforts of each individual can contribute to maintaining air quality in urban and rural communities, through the use of environmentally responsible modes of transportation (bicycle, walking, subway, bus, train, carpool). If you have to use an automobile, adopt ecologically responsible driving habits. Drive within speed limits, maintain your vehicule regularly and avoid letting en engine idle: small efforts can have a huge impact on air quality.

For more information, you can visit the following Web sites :

http://www.qc.ec.gc.ca/atmos/smog http://www.msss.gouv.qc.ca/sujets/santepub/ environnementale.html http://www.mddep.gouv.qc.ca/air/info-smog http://www.rsqa.qc.ca http://www.santepub-mtl.qc.ca/Environnement

Dissemination of Info-Smog warnings

Environment Canada will disseminate smog warnings as follows :

Internet site: htp://www.qc.ec.qc.ca/atmos/smog ;
Email and Fax;
Live media briefing by specialists.

The Ministère du Transport du Québec will disseminate smog warnings on their electronic panels located along highways of the Montreal and Quebec city area.

Ministère du Développement durable, de l'Environnement
et des Parcs :
Roger lemire
(418) 521-3820 ext. 4667
Fax (418) 643-9591
e-mail : roger.lemire@mddep.gouv.qc.ca

City of Montréal Environment Service :
Diane Boulet
(514) 280-4365
Fax (514) 280-4285
e-mail : diane.boulet@ville.montreal.qc.ca

Public Health Department of Central Montreal :
Norman King
(514) 528-2400 ext. 3245
Fax (514) 528-2459
e-mail : nking@santepub-mtl.qc.ca

Environment Canada - Quebec region :
Jacques Rousseau
(514) 496-5789
Fax (514) 283-7149
e-mail : jacques.rousseau@ec.gc.ca

	\| What's New \| About Us \| Your Environment \| Information/Publications \| \| Weather \| Home \|
	\| Français \| Contact Us \| Help \| Search \| Canada Site \|
		Important Notices and Disclaimers


	* Links to sites external to Environment Canada Links to sites external to Environment Canada are provided as a convenience and their inclusion in no way implies that Environment Canada endorses or accepts any responsibility for the content or use of these sites. As the organizations that maintain these sites may not be subject to the Official Language Act, information found on these sites may be presented only in the language in which it was written.