Office of the Fire Marshal Emergency Building Measures A Guide to Strengthen Emergency Management of High-Rise and High-Risk Buildings

7. Emergencies Due to Natural Disasters

7.1 Earthquakes
7.2 Severe Storms
7.3 Floods
7.4 Major Electrical Power Failures
7.5 Roof Collapse

Emergencies due to sudden and powerful natural events are capable of inflicting considerable damage to property and placing many lives at risk. These types of emergencies generally result from severe weather conditions or earthquakes. Subsequent flash floods that may follow can result in further property damage and risk to lives.

This section covers the procedures that should be taken in the event of a major emergency due to natural disasters. It provides the necessary steps that need to be taken by those who are directly responsible for building emergency preparedness as well as by the building occupants. The building occupants’ roles and responsibilities should always be included in the Emergency Plan and be available to them as a reference. Regardless of whether or not they have been delegated any formal responsibilities occupants play an integral part in effectively executing the Emergency Plan and ensuring their own personal safety. Their role is particularly important in buildings where delegated emergency personnel are not available 24 hours a day, seven days a week.

Many types of circumstances besides fire may require a building or portions of a building to be evacuated. Some of these circumstances are discussed in the following subsections of the guideline.

Other types of circumstances warranting evacuation and not discussed in detail could include: serious fires in a neighbouring building, a serious hazardous chemical spill involving the transportation of a dangerous product(s), forest fires, a large natural gas leak originating outside of the building, etc.

Usually in these types of situations, local authorities will likely be involved in responding to, and/or monitoring the emergency situation. Where applicable, building management should consult with authorities to determine an appropriate course of action. However, in some situations, a decision to evacuate may have to be made by building management on their own without the opportunity for consultation.

When circumstances warrant an evacuation, the building occupants must be notified in an appropriate manner, taking into consideration the serious nature and urgency of the situation.

For more information see: Emergency Management Ontario

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7.1 Earthquakes

Seismic activity level in Ontario is generally well below that experienced along Canada’s west and east coasts. Historically, areas along the Ottawa River and the St. Lawrence River have been the most active within the province. Over the past 30 years, this area has averaged 15 earthquakes per year with a magnitude of 2.5 or higher. By comparison, an annual average of only two or three earthquakes of this size occurs in Southern Ontario. Northern Ontario has even lower seismic activity, averaging one or two earthquakes over this period.

Nevertheless, going further back in history, earthquakes with a magnitude in excess of five on the Richter scale have been experienced in Ontario. As well, Ontario has felt the effects of earthquakes originating from nearby provinces and states. Therefore, some consideration should be given to preparing for such an event.

Building management should:

• Warn occupants to expect that the fire alarms and sprinklers will go off during an earthquake.
• Instruct occupants that it is very dangerous to try to leave a building during an earthquake because objects can fall on occupants. Many fatalities occur when people run outside of buildings, only to be killed by falling debris from collapsing walls and broken glass. Occupants are generally safer to stay where they are until the earthquake is over.
• Evacuate occupants once the shaking has stopped. Occupants should be evacuated using the stairs and moved quickly away from the building to prevent injury from falling debris.
• Call emergency services, as appropriate, and then give first aid as necessary. Do not try to move seriously injured people unless they are in immediate danger of further injury.
• Put out small fires quickly if this can be done without endangering personnel. This will prevent fires from spreading until firefighting resources become available. Fire is the most common hazard following earthquakes.
• Clean up flammable liquid spills immediately.
• Expect aftershocks.
• Warn occupants of fallen power lines and other hazards.
• Arrange for qualified people to inspect the building for damage that may have occurred.

For more information see: Earthquakes Canada

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7.2 Severe Storms

Thunderstorms, tornadoes, hail, blizzards, ice storms, high winds and heavy rain can develop quickly and hit hard, posing a threat to life and property. Some problems cannot be prevented. High winds will topple trees and heavy rains will cause rivers to flood. But some damage can be avoided or at least reduced, if precautionary measures are taken, such as knowing the type of storms common to your area and what time of year they are likely to strike.

How will building management know if a severe storm is approaching?

Environment Canada monitors the weather 24-hours a day, seven days a week. If a severe storm is on the horizon, the weather service issues watches, advisories and warnings through national, regional and local radio and television stations, and Environment Canada’s Weatheradio.

If a weather warning is issued for a tornado, it means that one or more tornadoes have been observed or are forecast for the specified area. Other warnings include those for a severe thunderstorm, blizzard, ice storm, high winds, heavy snow, snow squall, heavy rain and heavy freezing rain.

How can building management prepare for a severe storm?

Storms such as tornadoes often strike too quickly to allow management to provide instructions to occupants at the time they occur. Occupants must be instructed as to correct procedures in advance. For example, storms that are accompanied by high winds would require occupants to retreat to interior spaces away from windows.

Management should be aware that electrical power might be unavailable for an extended period of time. Therefore, backup generators and adequate fuel supplies may be very helpful in maintaining essential building services (e.g., heating). After a severe storm, it may be necessary to obtain the services of qualified personnel to inspect the building for damage that may not be readily identified.

For additional information on maintaining business continuity, see Appendix B.

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7.3 Floods

Building management should assess the threat of flooding to their building. Usually this is easily accomplished due to a history of similar earlier events. Alternatively, they can contact the local municipal planning office for flood information. Many insurance companies also have information on the potential for flooding in specified areas.

Where flooding is a potential risk, building management may wish to consider the following:

• Providing pumps, generators, sandbags, etc., for temporary flood relief.
• Providing permanent breakwaters and dikes where the flood potential is high.
• Evaluate the potential impact on ground level and underground tanks.
• Hazardous materials stored at or below grade moved to a safe location.
• Protection of drinking water sources.
• Impact of floodwater on high value and process equipment.
• Electrical hazards that may be created due to the presence of water (to both permanent and temporary wiring).
• Affect of flooding on the structural integrity of the building.
• Retain a list of qualified personnel and contractors who can be contacted to assess and repair flood damage.
• Arrange to have drinking water tested after a flood. This is particularly important in areas where drinking water is obtained from wells.

For more information see:
Canadian Mortgage and Housing – After the Flood - A Homeowners Checklist
Federal Emergency Management Agency, National Flood Insurance Program

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7.4 Major Electrical Power Failures

Any one of the occurrences described previously can cause or contribute to a major electrical power failure.

Backup generators and adequate fuel supplies may be very helpful in maintaining essential building services (e.g., lighting, heating). In buildings equipped with an emergency power generator, the equipment is required to be tested and maintained in accordance with the Ontario Fire Code. Pre-arrangements should be made to ensure additional fuel supplies could be made available upon demand, in situations where the power failure is for an extended period of time.

In buildings that are not equipped with an emergency power supply, building management and occupants need to be prepared in advance to cope with such a situation by having flashlights and a fresh supply of batteries.

When there is a potential for a power failure occurring simultaneously with the building evacuation, building occupants should avoid using the elevators as a means to leave the building. To be on the safe side, people should be instructed to proceed to evacuate the building promptly using the primary and secondary exits that would normally be used to evacuate the building during a fire. In large buildings, it may be necessary to stage the evacuation in order to ensure that it is conducted in an orderly manner.

For more information see:

Office of the Fire Marshal – Essential Fire Safety Information for Emergency Shelters
Office of the Fire Marshal – Safety Tips for Emergency Lighting and Heating During Power Failure
Office of the Fire Marshal – Safety Tips for Standby Generators
Electrical Safety Authority – Standby Generator Safety

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7.5 Roof Collapse

Buildings may experience roof collapse resulting from environmental occurrences such as high winds, tornados, snow, water and ice loading, to list a few.

Building owners and property managers should be aware of the potential for roof failure resulting from these effects. Where wind and snow-loading information is not available for the existing structure, property management should consult with a professional engineer and /or architect to assist in analyzing the integrity of the existing structure.

Based upon information of this nature, tolerable and un-tolerable wind and snow loading conditions can be identified. Procedures can be adopted that would identify conditions when unsafe loads may be experienced and incorporate safe practices for reducing excessive snow and ice loads.

When intolerable conditions are expected or imminent, evacuation may be appropriate.

For more information see:
Ministry of Labour – Hazard Alert – Snow Loading and Roof Failures

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