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Earthquakes can be deadly. The table below shows the tolls in the most
deadly earthquakes in history:   Most Destructive Known Earthquakes on Record in the World (50,000 deaths or more) Listed in order of greatest number of deaths
  * Official casualty figure: estimated death toll as high as 655,000   ** Note that these dates are prior to 1000 A.D. No digit is missing     What can be done to mitigate the hazardous effects of earthquakes?     Research and Forecasting The ultimate method for reducing the severity of earthquake damage and loss of life is dependable earthquake prediction. Early warning of seismic events insures that appropriate agencies and personnel have the time to adequately prepare and respond to the pending disaster. Methods used by researchers in attempting to predict earthquakes include: change in groundwater levels, electrical conductivity, changes or deformation of the ground surface, and changes in the strain prior to an event. These methods, however, are not consistently reliable. Consequently, predicting earthquakes is a difficult proposition. Most geologists, in fact, believe that truly accurate earthquake forecasting is something that will not appear for quite a while.   There are, however, companies that provide earthquake forecasts to subscribers for a fee. One such company is GeoForecaster, Inc. Click here to learn more about the methodology GeoForecaster follows in attempting to predict earthquake activity.     Earthquake Risk and Building Design Seismic hazard maps have been developed by various agencies. The map below, for example, shows earthquake risk in the coterminous United States.  
    Structures that are built in high-risk regions must be engineered to withstand the potential damage of an earthquake, especially in areas where liquefaction - the process by which water-saturated sediment temporarily loses strength and acts as a fluid - may occur. Liquefaction can happen as a result of earthquake shaking.   According to the Southern California Earthquake Data Center (SCEDC), most buildings are constructed only to withstand the downward pull of gravity. However, in an earthquake-susceptible area, buildings also must be able to withstand the sideways forces that an earthquake produces. The following items are crucial in an earthquake-safe building:   The building must have a strong foundation. All components of the building must be securely connected together. The building must be made of strong materials. The building's plumbing must be protected.     There are four main earthquake-related considerations when constructing a building in Canada. They are:   Geographical location Type of structure and the materials used Type of soil surrounding the structure The importance of the building during an earthquake     Personal Safety People can also take individual steps to ensure their safety both during and after an earthquake. The Federal Emergency Management Agency (FEMA) recommends taking the following steps:   During an Earthquake Drop, cover, and hold on! Move only a few steps to a nearby safe place. It is very dangerous to try to leave a building during an earthquake because objects can fall on you. Many fatalities occur when people run outside of buildings, only to be killed by falling debris from collapsing walls. You are safer to stay where you are.   If you are in bed, hold on and stay there, protecting your head with a pillow. You are less likely to be injured staying where you are.   Broken glass on the floor has caused injury to those who have rolled to the floor or tried to get to doorways.   If you are outdoors, find a clear spot away from buildings, trees, streetlights, and power lines. Drop to the ground and stay there until the shaking stops. Injuries can occur from falling trees, streetlights and power lines, or building debris.   If you are in a vehicle, pull over to a clear location, stop and stay there with your seatbelt fastened until the shaking has stopped. Trees, power lines, poles, street signs, and other overhead items may fall during earthquakes. Stopping will help reduce your risk, and a hard-topped vehicle will help protect you from flying or falling objects. Once the shaking has stopped, proceed with caution. Avoid bridges or ramps that might have been damaged by the quake.   Stay indoors until the shaking stops and you're sure it's safe to exit. More injuries happen when people move during the shaking of an earthquake. After the shaking has stopped, if you go outside, move quickly away from the building to prevent injury from falling debris.   Stay away from windows. Windows can shatter with such force that you can be injured several feet away.   In a high-rise building, expect the fire alarms and sprinklers to go off during a quake. Earthquakes frequently cause fire alarm and fire sprinkler systems to go off even if there is no fire. Check for and extinguish small fires, and, if exiting, use the stairs.   If you are in a coastal area, move to higher ground. Tsunamis are often created by earthquakes.   If you are in a mountainous area or near unstable slopes or cliffs, be alert for falling rocks and other debris that could be loosened by the earthquake. Landslides commonly happen after earthquakes.     After The Earthquake Check yourself for injuries. Often people tend to others without checking their own injuries. You will be better able to care for others if you are not injured or if you have received first aid for your injuries.   Protect yourself from further danger by putting on long pants, a long-sleeved shirt, sturdy shoes, and work gloves. This will protect you from further injury by broken objects.   After you have taken care of yourself, help injured or trapped persons. If you have it in your area, call 9-1-1, then give first aid when appropriate. Don't try to move seriously injured people unless they are in immediate danger of further injury.   Look for and extinguish small fires. Eliminate fire hazards. Putting out small fires quickly, using available resources, will prevent them from spreading. Fire is the most common hazard following earthquakes. Fires followed the San Francisco earthquake of 1906 for three days, creating more damage than the earthquake.   Leave the gas on at the main valve, unless you smell gas or think it's leaking. It may be weeks or months before professionals can turn gas back on using the correct procedures. Explosions have caused injury and death when homeowners have improperly turned their gas back on by themselves.   Clean up spilled medicines, bleaches, gasoline, or other flammable liquids immediately and carefully. Avoid the hazard of a chemical emergency.   Open closet and cabinet doors cautiously. Contents may have shifted during the shaking of an earthquake and could fall, creating further damage or injury.   Inspect your home for damage. Get everyone out if your home is unsafe. Aftershocks following earthquakes can cause further damage to unstable buildings. If your home has experienced damage, get out before aftershocks happen.   Help neighbours who may require special assistance. Elderly people and people with disabilities may require additional assistance. People who care for them or who have large families may need additional assistance in emergency situations.   Listen to a portable, battery-operated radio (or television) for updated emergency information and instructions. If the electricity is out, this may be your main source of information. Local radio and local officials provide the most appropriate advice for your particular situation.   Expect aftershocks. Each time you feel one, drop, cover, and hold on! Aftershocks frequently occur minutes, days, weeks, and even months following an earthquake.   Watch out for fallen power lines or broken gas lines, and stay out of damaged areas. Hazards caused by earthquakes are often difficult to see, and you could be easily injured.   Stay out of damaged buildings. If you are away from home, return only when authorities say it is safe. Damaged buildings may be destroyed by aftershocks following the main quake.   Use battery-powered lanterns or flashlights to inspect your home. Kerosene lanterns, torches, candles, and matches may tip over or ignite flammables inside.   Inspect the entire length of chimneys carefully for damage. Unnoticed damage could lead to fire or injury from falling debris during an aftershock. Cracks in chimneys can be the cause of a fire years later.   Take pictures of the damage, both to the house and its contents, for insurance claims.   Avoid smoking inside buildings. Smoking in confined areas can cause fires.   When entering buildings, use extreme caution. Building damage may have occurred where you least expect it. Carefully watch every step you take.   Examine walls, floor, doors, staircases, and windows to make sure that the building is not in danger of collapsing.   Check for gas leaks. If you smell gas or hear a blowing or hissing noise, open a window and quickly leave the building. Turn off the gas, using the outside main valve if you can, and call the gas company from a neighbour's home. If you turn off the gas for any reason, it must be turned back on by a professional.   Look for electrical system damage. If you see sparks or broken or frayed wires, or if you smell burning insulation, turn off the electricity at the main fuse box or circuit breaker. If you have to step in water to get to the fuse box or circuit breaker, call an electrician first for advice.   Check for sewage and water line damage. If you suspect sewage lines are damaged, avoid using the toilets and call a plumber. If water pipes are damaged, contact the water company and avoid using water from the tap. You can obtain safe water from undamaged water heaters or by melting ice cubes.   Watch for loose plaster, drywall, and ceilings that could fall.   Use the telephone only to report life-threatening emergencies. Telephone lines are frequently overwhelmed in disaster situations. They need to be clear for emergency calls to get through.   Watch animals closely. Leash dogs and place them in a fenced yard. The behaviour of pets may change dramatically after an earthquake. Normally quiet and friendly cats and dogs may become aggressive or defensive.     Earthquake Safety Kit Things to keep on hand, if you live in an earthquake-sensitive area   Food (enough for each person for 72 hours) Water (enough for each person to have 4 litres each, per day) Bedding, clothes, and shelter (such as a tent). Don't forget heavy work gloves. First aid kit Candles Flashlights Battery-powered radio Matches Personal and sanitary products
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