Read more about the Haiti earthquake in Slate.
Following the earthquake in Haiti, the United States and other countries are sending search-and-rescue teams to help sift through the ruins for survivors. Groups in Haiti are already digging through the rubble with their bare hands. Do you have to use your hands, or is there a better way to search for bodies in rubble?
It often comes down to scooping up the rocks one by one. Sophisticated equipment and techniques are more useful in the initial stages, before potential survivors have been located. Construction vehicles like loaders and backhoes are sometimes employed in the first hours of the search, to move away the perimeter rubble in which people are rarely found. Then urban search-and-rescue teams use robots, cameras, and dogs to sort through rubble quickly and safely. However, once a survivor is located, the team generally ends up moving rocks by hand, since heavy machinery would pose a serious risk to the survivors buried underneath.
A search-and-rescue team's first task is to determine whether the parts of a building that remain erect are structurally sound. Most teams include civil engineers who identify which walls are likely to stand and which should be braced prior to entry. If there is any question, searchers can use a pole- or tube-mounted camera to look for signs of life. High-tech teams also employ small robots with wheels, tank treads, cameras, and arms to move debris. (Next-generation search-and-rescue robots may look more like snakes than small tanks.) The robots can squeeze into spaces a human can't—most of them fit into a backpack—and they can enter hazardous environments like smoke- or dust-filled rooms.
While the new robots are nifty, trained dogs are still important. Rooting around for survivors takes an enormous toll on the canines, as the rocks hurt the pads of their feet and they quickly become exhausted. (Some rescue dogs wear protective booties.)
A fair amount of strategy goes into the search. Rescuers attempt to determine whether victims might be concentrated in one area of the building—for example, if there had been a gathering in an auditorium—and focus the search in those rooms. Alternatively, they may go straight for a particularly important victim. (Searchers might place a high priority on finding the head of the U.N. mission in Haiti, which collapsed in the quake.)
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Explainer thanks Lois Clark McCoy of the National Institute for Urban Search and Rescue.
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