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Alerting under Imminent Threat: Guidance on alerts issued by outdoor siren and short message alerting systems



Erica D. Kuligowski, Amanda Kimball


The National Institute of Standards and Technology (NIST)’s Technical Investigation of the 2011 Joplin, MO tornado identified that no widely accepted standards exist for emergency communications in tornado events and more specifically, policies involving the use of communication systems to alert the public in advance of tornadoes. This publication provides evidence-based guidance for communities on the creation and provision of public alerts, including both alerts provided by outdoor siren (warning) systems and “short messages” sent by social media or other short message service (SMS) platforms. It is the hope that this guidance can eventually be used as input for standardization, through codes and standards, of the procedures and practices for outdoor siren systems and short message alerts used by communities across the United States. Standardization of emergency communication policies and procedures could occur at multiple levels, including among multiple jurisdictions, state-wide, regionally, or even nationally. This document begins with a brief background on alerting systems, focusing specifically on outdoor siren systems and short message alerts. The next section presents the methods used for the development of evidence-based guidance on public alerts, including methods for review of literature on public response to public alerting systems, the development of preliminary guidance based on these reviews, and the finalization of the guidance presented here in this report. Then, guidance for communities on the creation and provision of public alerts for those under imminent threat is presented. This document ends with a discussion on unanswered questions, providing opportunities for further research into various areas of public alerting.
Technical Note (NIST TN) - 2008
Report Number


alerts, disasters, emergency communication, mass communication, short messages, Twitter, Wireless Emergency Alerts, IPAWS, public response, emergency warnings, tornadoes, outdoor siren systems
Created August 16, 2018, Updated November 10, 2018