Emergency communication system
161 people were killed and at least 990 injured when an EF5 multiple-vortex tornado hit Joplin, Missouri. Because Joplin is located in a tornado-heavy area of the country, many people considered the tornado sirens routine and ignored them. Instead, many residents waited until they received confirmation from another, non-routine, source, such as seeing the tornado, a radio or TV report, or hearing a second siren. In the aftermath, an assessment team recommended that emergency warnings take risk perception into account to convey a sense of urgency. NOAA Officials are considering ways to change the warning system to distinguish smaller tornadoes from more deadly ones.
2011 Joplin tornado
Engineers have criticized the tilt up construction of the Home Depot in which all but two of its walls collapsed in a domino effect after the tornado lifted the roof, killing seven people in the front of the store (although 28 people in the back of the store survived when those walls collapsed outwards). Home Depot officials said they disagreed with the study published by "The Kansas City Star" and said they would use the tilt up practice when they rebuild the Joplin store. On June 1, The Home Depot said it would have a new temporary building built and operational within two weeks. In the meantime, it opened for business in the parking lot of its demolished building. On June 20, The Home Depot opened a temporary building constructed by the company's disaster recovery team.