Final Report, National Institute of Standards and Technology (NIST) Technical Investigation of the May 22, 2011, Tornado in Joplin, Missouri

This is the final report of the National Institute of Standards and Technology (NIST) investigation of the May 22, 2011 tornado in Joplin, Missouri, conducted under the National Construction Safety Team Act. This report describes the wind field of the tornado and how the wind pressures and windborne debris damaged and destroyed thousands of buildings; the emergency communications before and during the tornado and how the public responded; the influence of tornado hazards and public response and building and designated shelter area performance on survival and injury; and areas of current building and emergency communications codes, standards and practices that warrant revision. Also described in this report is the means by which NIST reached its conclusions. NIST collected large numbers of documents, photographs, videos, and building plans; developed a computer model of the wind field of the tornado as it crossed the City of Joplin; analyzed the performance of a range of building types for life safety and functionality; interviewed many survivors of the tornado, developed an evidence–based explanation for decisions made and actions taken by the public in response to the tornado; and analyzed the factors affecting life safety outcomes. The report outlines 47 findings related to the May 22, 2011, Joplin tornado and concludes with a list of 16 recommendations for action in areas of improved measurement and characterization of tornado hazards, new methods for tornado resistant design of buildings, enhanced guidance for community tornado sheltering, and improved and standardized emergency communications.