A Department of Homeland Security Emeritus Center of Excellence led by the University of Maryland

A consortium of researchers dedicated to improving the understanding of the human causes and consequences of terrorism

Optimizing WEAs for Mobile Devices


Optimizing WEAs for Mobile Devices

November 25, 2014Rachael Romano

Wireless Emergency Alerts (WEA) are used to warn the public about imminent threats, and to encourage preventative action. Recently the National Consortium for the Study of Terrorism and Responses to Terrorism (START) conducted research to optimize the message contents of these alerts delivered over mobile devices on behalf of the Department of Homeland Security Science and Technology Directorate’s First Responders Group. Researchers looked at aspects such as order of information, length, message source and public perception of WEAs.

START researchers,  Hamilton BeanBrooke LiuStephanie MaddenDennis MiletiJeannette Sutton and Michele Wood, conducted experiments, focus groups, think-out-loud interviews and surveys of a natural disaster threat. They concluded that shorter alerts (90- and 140- characters) do not increase public understanding of the situation. The team proposed methods to increase public understanding of these messages including education and marketing campaigns; maps and graphics; and longer messages.

Key findings of the study revealed:

  • Ordering the message elements as follows: source, guidance, hazard, location and time, had a slight advantage.
  • It may be more productive to have one recognizable source of information for the public. If the source is not recognizable, an educational and marketing campaign could increase the speed at which receivers respond. 
  • Including a detailed map, which includes affected areas and unaffected areas relative to the receiver’s location increases comprehension.
  • The optimal message length for the public to take action is 1,380 characters, including the possible addition of a URL, to assist receivers in further research. This also increases response time.
  • Messages should not assume the public knows “basic alert concepts” or acronyms. In addition, messages created to elicit fear may not effectively motivate preventative action.

Project details can be found here.