All procedures to warn the public of imminent danger, including the operation of the public alert system and sending notification messages.
Measures and methods to limit the effects of risks on society and the environment.
BLEVE Boiling Liquid Expanding Vapor Explosion. A catastrophic rupture of a tank of liquefied gas followed by an explosive evaporation 1.
Total or combination of all forces and resources available within a community, society or organization that can reduce risks or effects resulting from a risk.
All actions and methods at all levels of society whose aim is to understand risks, eliminate or reduce their occurrence, attenuate their potential effects or, during and after disaster, to reduce harmful consequences.
Community alert service
The emergency message service sent to all residents via landline using the 9-1-1 database.
Situation, condition, practice or substance that because of its characteristics or intrinsic properties has the potential to cause damage to people, property or the environment.
The deterministic approach is based on the evaluation of the consequences of credible (or conceivable) accidents without explicitly quantifying the probability of these accidents.
A tangible or intangible element in an environment that is susceptible to a natural or anthropogenic risk and to prejudice or damage.
Falling rock or debris
Weakened infrastructures can result in falling rock or debris, causing major accidents and posing a threat to residents’ safety.
Freezing rain is liquid precipitation with a temperature lower than 0°C that freezes once it comes into contact with the ground or other objects (trees, electrical wires, etc.) Freezing rain can make surfaces very slippery for drivers and pedestrians, and cause accidents such as falling power lines.
Precipitation in the form of ice granules with a diameter of 5 mm or more. Hail forms in the centre of storms and hailstones can pick up water on their way down, becoming bigger, heavier and more dangerous. Damage caused by hailstorms can be major, especially to cars and houses. Source: Natural Resources Canada, The Atlas of Canada.
Environment Canada (2006) defines heat and humidity as extreme when outdoor temperatures rise above 30 °C and humidex values are higher than 40, no matter how long the heat wave lasts.
Summer storms are caused by rapid elevation of hot, humid air and can cause intense precipitation known as heavy or torrential rain. Heavy rain can cause flooding, sewer backups and damages.
Pileups of floating ice or accumulations of frozen branches and twigs. Sometimes ice jams have to be dynamited to unclog the waterway, avoid catastrophic floods upstream or major damages downstream caused by the flood wave that follows the breakage of an ice jam.
Landslides occur when a mass of earth moves towards the bottom of a slope, most often after an earthquake. In Montréal, the risk is low because the highest elevation on the island, besides Mount Royal, is the Saint-Jacques cliff escarpment, and this area is not at risk for a major earthquake.
Ordered division of activities and people with a view to the future and with respect to an area’s spatial, social and economic constraints.
When the ground is soaked with water, it can cause a liquefaction phenomenon during an earthquake.
Major disaster According to the Civil Protection Act (L.R.Q., chapitre S-2.3, art. 2), “an event caused by a natural phenomenon, a technological failure or an accident, whether or not resulting from human intervention, that causes serious harm to persons or substantial damage to property and requires unusual action on the part of the affected community, such as a flood, earthquake, ground movement, explosion, toxic emission or pandemic.”
Major industrial accidents
Ground movements can cause breakages to at-risk facilities, creating chemical leaks or major fires.
OSCAM’s structure comprises 10 agglomeration missions and four local missions. A civil protection mission is defined as a “civil protection duty or duties to perform, especially during response and recovery, that require delivery of services specific to the field of civil protection.”
All measures and activities whose aim is to reinforce disaster response capacities.
All permanent measures that aim to eliminate risks, reduce the possibility of their occurrence or attenuate their potential effects.2
The probabilistic approach is based on risk. The objective is to evaluate the severity of potential accidents and estimate the probability of their occurrence.
Probability of occurrence
The likelihood of a risk will occur at a specific intensity (probability of occurrence can be expressed qualitatively or quantitatively).
Post-disaster decisions and actions to restore social, economic, physical and environmental conditions of the community and reduce the risk of disaster.
The ability of a system, community or society that is potentially exposed to risk to adapt, resist or change in order to establish and maintain acceptable structures and level of functioning.
Measures taken immediately before, during and after a disaster to save lives, ensure residents’ essential needs are met and safeguard property and the environment.
A phenomenon, event or human activity that could result in losses of human life or injuries, damages to property, social or economic disturbance, or environmental degradation.
The proportion to which an exposed element is likely to be affected by a risk.
Development which meets present-day needs without compromising the capacity of future generations to meet theirs.
Tornadoes are columns of air that spin at a high speed. They are small in scale but can be very violent. They strike quickly, randomly, and often without warning. Tornado winds can be as high as 100 metres per second During a tornado the damage is due to wind as well as an extremely sudden drop in pressure. Source: Natural Resources Canada, The Atlas of Canada.
A tsunami is a series of massive waves that are often caused by the shock wave of an underwater earthquake or other phenomena. When waves approach the shore and the water becomes more shallow, they become higher. A tsunami can occur without warning and cause flooding and major damage to coastal areas.
Urban heat island
The expression “urban heat islands” means the difference in temperature observed between urban areas and surrounding rural areas. Observations have shown that temperatures in urban centres can be as much as 12 °C higher than neighbouring areas.