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817TECHNICAL DATADATA SUBJECT TO CHANGE WITHOUT NOTICE.SEISMIC CONSIDERATION (CANADA)Although earthquakes can occur anywhere in the world, certain areas have a higher probability of experincing damaging ground motion caused by earthquakes. In areas where earthquakes are highly probable, enclosures can be provided with additional stiffening and hold down bracing in order to meet various seismic ratings. In order to assist in the necessity of providing features over and above our standard design,we have provided seismic information for North America. A simplified version of the seismic hazard map of Canada is shown below. The 5 colors in the simplified map are not intended to represent building code zones, they merely show the relative hazard across the country. In Canada the Natural Resources Canada no longer assign Zones to seismic hazard. Since 2005 they have provided site specific spectrol and peak acceleration values for all locations in Canada. Information on the National Building Code of Canada (NBCC) seismic hazard maps can be found in the earthquake hazard section of the website at: http://earthquakescanada.nrcan.gc.ca/index-en.phpThe U.S. Geological Survey (USGS) produces the National Seismic Hazards Maps. These maps are revised every 6 years or so to reflect newly published or thoroughly reviewed earthquake science and to keep pace with regular updates of the building code. The latest update of this map was in 2008 and it supersedes all previous maps. A copy of this map is shown below. Colors on this map show the levels of horizontal shaking that have a 2-100 chance of being exceeded in a 50 year period. Shaking is expressed as a percentage of g (g is the acceleration of a following object due to gravity). (Credit image courtesy of the U.S. Geological Survey). This USGS seismic map is the basis for seismic design provisions of building codes, insurance rate structures, earthquake loss studies, retrofit priorities, and land-use planning. The web site for the USGS is: http://earthquake.usgs.gov/research/hazmaps/SEISMIC CONSIDERATION (U.S)