planning for CMAS. Michael Lindell, Texas A&M University, provided an overview of what is known from past research about the process of sending alerts and warnings and how people respond to them, and Joseph Trainor, University of Delaware, went on to debunk key misconceptions about the public response to alerts and warnings and about other behavior during a disaster. Garry Briese, Briese and Associates, moderated the second session and commented on the use of CMAS to deliver alerts. This chapter provides an integrated summary of these presentations and the discussions that followed, organized by topic.



Regarding the wide use of cellular telephones and other mobile wireless devices in the United States, CTIA—The Wireless Association® reported more than 290 million U.S. subscribers by mid-2010, a greater than 90 percent penetration rate.2 Cellular networks thus provide an attractive opportunity for delivering alerts and warnings, complementing the mechanisms used today—broadcast radio and television, cable television, National Oceanic and Atmospheric Administration (NOAA) weather radio, reverse-911 (which allows jurisdictions to dial a list of telephone numbers and play recorded messages), and sirens. Cell phones are generally kept close at hand in a variety of settings; their users can be reached on the street, in automobiles, and at home or at work, and audio alerts can even awaken people when they are sleeping. Also, the ability to target messages to a cell phone’s actual location makes it possible to target more precisely those individuals who would be most at risk in a crisis situation. Cell phones thus seem well positioned to fill gaps in message-receipt coverage by traditional systems—as well as additional gaps that may open up as the reach of traditional broadcast media diminishes.

Establishment of CMAS

The Warning, Alert, and Response Network (WARN) Act of 2006,3 which establishes a national all-hazards alert system and calls for the use of multiple technologies, including wireless telecommunications, was


Statistics from CTIA Semi-Annual Wireless Industry Survey, available at; and CTIA Wireless Quickfacts, available at Note that a penetration rate calculated, as here, by dividing subscribers by the U.S. population is likely to be an overestimate, because some individuals may have multiple subscriptions.


Public Law 109-347.

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