As the horrific death toll in Haiti has so tragically demonstrated, the primary defense against earthquakes is to have buildings strong enough to withstand their destructive force. It is estimated that at least 150,000 Haitians perished in the magnitude-7.0 temblor and aftershocks that flattened much of Port-au-Prince and surrounding areas on Jan. 12, and it is feared the final death toll will be significantly higher. The vast majority of victims died inside buildings that turned into death traps as they collapsed.
One of the world's most impoverished nations, Haiti has no national building codes and most of its structures were not built to withstand earthquakes. Because wood is scarce in Haiti, most buildings there are constructed of unreinforced cinder blocks and bricks, which have much lower resistance to earthquakes than wood- or steel-framed structures. They have a tendency to break and crumble rather than bend when struck by strong seismic forces. Shacks made of sheet metal, commonplace in Haiti, also fare very poorly in earthquakes.
Making matters worse, the cinder blocks used in Haiti are often made of substandard materials. Grinding poverty and a lack of building codes make it all too tempting for building material manufacturers to save money by lessening the percentage of concrete and adding more sand, resulting in a product that is brittle and even more prone to failure during quakes. In addition, a common building practice in Haiti is to simply stack the blocks atop each other without reinforcing them with metal bars that would help to hold them together in the event of a quake.
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