May 23, 2013
When a storm like the one that hit Moore, Okla., this week strikes, no house can withstand the blow. So why aren’t shelters more widely used?
The Texas Tech University Debris Impact Testing Lab certifies above-ground shelters as capable of withstanding EF5 storms. "If the shelter has been tested as an F5, it's good for a 250 mile per hour tornado," says Larry Tanner, a research associate at the National Wind Institute and Debris Impact Testing Lab.
The lab also recommends indoor shelters above cellars only accessible from the outside, since residents are less likely to use outdoor shelters and often encounter flying debris while trying to reach them.