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Action 4: Prepare Warnings in Advance

Download full checklist (PDF) • See phased implementation plan

Strengthen the region’s ability to deliver actionable public warnings following a nuclear detonation through well-chosen technologies and organizational procedures.

In the nuclear terrorist context, effective public communication is essential to saving lives, reducing injuries, relieving distress, and keeping fears in proportion to risk. Community preparedness for fallout must include advance preparations for the effective release of public warnings and guidance in an actual incident. In a nuclear detonation, the communications infrastructure normally used to disseminate official warnings will be degraded. Contingency plans must account for these material impacts and incorporate redundant means of disseminating key messages. Also, public communication strategies should be grounded in what is currently known about the social and psychological processes that people go through from the point of first hearing a warning to acting on the information.40


Task 4.1—Develop pre-scripted, pre-vetted, and scientifically based fallout warning messages tailored to the specific needs of the community.

Effective fallout warning messages about protective actions during the immediate response phase should be a jurisdiction’s top priority because of their life-saving potential (although a community’s information needs should be anticipated for all phases of the disaster). It is just as important to communicate to people who are not at risk of fallout exposure as it is to those who are. Unnecessary evacuation impedes logistics and strains resources necessary for those living in high-risk areas. Information gleaned from properly conducted education campaigns (see Action 2) and technical knowledge of the community should be used to tailor these warning messages for the unique circumstances for each area. The format of an effective generic warning message (one that maximizes the listener’s likelihood of taking appropriate actions) is summarized and then modeled in Formula for Writing an Effective Message for Postdetonation Public Warning.41 Sample Fallout Warning Messages for the Post–Nuclear Detonation Period, includes fallout warning message templates developed by Los Angeles County.22 Communities are also encouraged to review key public messages crafted by a multidisciplinary group of technical experts and practitioners for the first 72 hours following a detonation.42 These messages are undergoing further refinement, so jurisdictions should watch for updates. FEMA is currently developing several short videos that can be disseminated after a nuclear detonation. Postdetonation messages should be consistent with the information delivered during pre-incident education.

Task 4.2—Address organizational issues related to effective warning dissemination (eg, who can “trigger” a public message and when).

In the context of a nuclear detonation, providing rapid public warnings about protective behaviors is critical because the fallout hazard is greatest in the early minutes to hours following the explosion. Some jurisdictions lack written procedures on “who” is authorized and responsible for activating a public warning protocol.43 Similarly, plans often fail to document criteria that should trigger the release of public warning messages.43 These omissions can lead to costly delays in notifying the public. Therefore, written plans and procedures for a nuclear detonation should document the role(s) authorized to activate the public warning protocol as well as the criteria that will be used, and they should outline local/regional contingency plans in the event the local Emergency Operations Center (tasked with issuing messages) is nonfunctional. Triggering criteria, for example, could include the primary sources of data (eg, using local meteorological forecasts rather than awaiting federal mapping [see Action 5]). Just as criteria need to be established to trigger initial warning messages, jurisdictions should also determine what indicators will lead to a change in warning message content. For instance, a drop in radiation levels and removal of debris from the roadway may trigger the change from a sheltering message to an evacuation message for certain areas.

Task 4.3—Devise low-tech, redundant means for issuing public warning messages, assuming a degraded telecommunications infrastructure.

EMP effects and the surge in information demand will severely strain surviving telecommunications infrastructure, throwing up barriers to the dissemination of public warning messages. Thus, plans should include lower-tech means to communicate warnings (eg, radio broadcasts, megaphones, 2-way radios, National Weather Service warning radios, amateur radios, loudspeakers, sirens, alarms, PA systems) to augment usual means. For example, the Indian Ocean tsunami and the Haiti earthquake highlighted the importance of radio broadcasts after extensive infrastructure damage and disruption. The use of cell phone texting—which may be available the farther one gets from ground zero—has also been found to be very effective in some disaster settings because it does not require very much bandwidth. Authorities should plan to use any and all communication means at their disposal following a detonation.

Task 4.4—Plan to establish hotlines for an acute demand for health-related information; monitor for rumor control.

Plans should be in place for establishing emergency call-in banks that can deliver pre-scripted messages and dispel rumors. Some people may not be able to access these resources for some time, but many people outside affected areas will need reassurance that they are not in harm’s way. Rumors are a normal indicator of people’s urgent need to gather and confirm useful information during ambiguous situations, particularly those with a safety element, and they become intensified in the absence of meaningful, authoritative information.44 Emergency professionals thus should review callers’ concerns and monitor both “old” and “new” media (see Task 4.5) to act swiftly in correcting misinformation and in refining public messaging.

This is especially important with social media that can instantaneously propagate information. For example, in the aftermath of the 2004 tsunami, a tsunami warning was circulated in Indonesia, only to be revealed as an anonymous hoax.45 More recently, a fake Short Message Service (SMS, also known as text messaging), purporting to be from the BBC, warned that radiation from the Fukushima nuclear plant had leaked beyond Japan and that people should start taking precautions; reportedly this message frightened many in Asia.46

Task 4.5—Monitor public peer-to-peer communications to enhance situational awareness postdetonation and to refine official warnings.

In disasters, people no longer rely exclusively on official sources and traditional media to find useful, credible information. Some individuals are turning to community websites, social networking sites, personal blogs, public texting systems like Twitter, and photo and mapping sites to gather and disperse helpful information and to coordinate a broader response to disaster.47 For example, some residents who wanted timely, local news during the 2007 California wildfires relied on the Twitter postings of 2 men who compiled reports from friends, monitored news broadcasts, and snapped firsthand photos of their surroundings. The men aggregated this information to provide rapid updates about evacuations, meeting points, and places to gather supplies.48

The use of social media in a disaster, however, is an emergent phenomenon. Some disaster research suggests that while younger people may rely greatly on internet-based communication, older adults making decisions about evacuations typically do not—at least not yet. Planners should be aware of these new, citizen-generated flows of crisis communications, tap into them to enhance situational awareness postdetonation, monitor them to refine official warnings and messages, and take proactive measures to develop their own social media capabilities.