Sorenson, J. H. and D.S. Mileti, 1988: Warning and evacuation: Answering some basic questions. Industrial Crisis Quarterly 2, 2(3 & 4), 195-209.

The authors analyze data from numerous behavioral studies of public evacuation response. It address five common questions asked by emergency managers and personnel and attempts to clarify some common myths and misled assumptions. The five questions it answers are: 1) how long does it take to warn a population about a crisis? 2) how many people evacuate in an emergency situation 3) when do people evacuate? 4) do people evacuate unnecessarily? and 5) where do people go when they evacuate? Conclusions to these questions are: Emergency response systems are usually able to effectively issue a warning in about 3-4 hours. More rapid issuances can be achieved, but it is found that lead times under one hour result in portions of the population not being warned. Additionally, of the studies analyzed, 50% of the public received warnings informally from friends and family, which quickened the warning process and is recommended by emergency personnel. The time it takes an individual to respond to a warning depends on the hazard, the time to impact, and the severity of the hazard. Rarely do people immediately evacuate unless the threat is imminent. Furthermore, the public is found to assess their personal risk and then make the right decision for them. It is recommended that warnings provide sufficient risk information in enough detail to spur appropriate actions. Lastly, it is found that most people do not go to community shelters during hazard warnings.