Skip Navigation U.S. Department of Health and Human Services
Agency for Healthcare Research Quality
Archive print banner

Public Health Emergency Preparedness

This resource was part of AHRQ's Public Health Emergency Preparedness (PHEP) program, which was discontinued on June 30, 2011, in a realignment of Federal efforts.

This information is for reference purposes only. It was current when produced and may now be outdated. Archive material is no longer maintained, and some links may not work. Persons with disabilities having difficulty accessing this information should contact us at: Let us know the nature of the problem, the Web address of what you want, and your contact information.

Please go to for current information.

Chapter 3: Pilot Test Sites

New York City (NYC) and Los Angeles served as pilot test sites for the Mass Evacuation Transportation Model.

3.1. New York City

During the Task Order, project staff had the opportunity to test the model in New York City. In early 2006 the New York City OEM was developing a plan to evacuate hospitals and nursing homes that would be affected by a major hurricane. AHRQ and project staff met with OEM officials and agreed that the pilot test would benefit both OEM and the AHRQ project. A working group with representatives from OEM, City hospitals and nursing homes, and City transportation agencies was formed to help guide the project.

The scenario was a Category 4 hurricane. A hurricane of this magnitude has reached the City on average every 50 years, and it had been roughly 50 years since the last Category 4 hurricane. OEM officials determined that 24 hospitals and 61 nursing homes located in areas in NYC would be underwater in such an incident. It was also assumed that an evacuation would begin 72 hours before the hurricane reached the City.

As detailed in Appendix 2, project staff, with help from the working group, obtained a variety of data needed to run the model for this scenario, including patient acuity levels, inter-facility transport times, vehicle fleet sizes, and loading and unloading times. Project staff also worked closely with OEM staff throughout the project to refine assumptions. The modeling results are summarized in Appendix 2. In addition to estimating the total evacuation time, project staff ran the model will a wide variety of inputs in order to understand the sensitivity of different inputs to the total evacuation time.

Return to Contents

3.2. Los Angeles

During the first half of 2007, project staff worked with the Los Angeles Emergency Preparedness Department (EPD) to plan and conduct an earthquake table top exercise. In the scenario, three local hospitals—Kaiser/Los Angeles, Children's Hospital/Los Angeles, and Hollywood Presbyterian—had to be evacuated because of a major (7.1) earthquake.

The exercise was held on June 6, 2007, in Los Angeles. Approximately 75 persons attended, including representatives from the three evacuating hospitals, the regional hospital association, various city and county agencies, and the military. Dr. Paul Biddinger, the project's co-principal investigator, designed the table top and was the lead facilitator.

Prior to the table top, project staff worked with officials from the Los Angeles EPD to agree on modeling assumptions and to obtain data for the baseline evacuation time estimate (go to Appendix 3 for all the assumptions and input data). The most important assumptions included:

  • Roughly 40 percent of the patients at the three hospitals would need transport via an ALS ambulance.
  • Only 5 percent of the county's fleet of ALS ambulances could be dedicated to the evacuation.
  • Traffic would be significantly slower—travel times were assumed to be twice the normal travel time.

Based on these assumptions, the estimated total evacuation time for all the patients in the three hospitals was 105 hours. During the table top, the attendees were shown how total evacuation time varied under different conditions, including different traffic conditions, number of available ALS ambulances, patient loading times, and standards of care (go to Appendix 3 for the graphs presented to the attendees). This prompted attendees to consider the importance of:

  • Securing additional ALS ambulances (because of, for example, the non-linear effects on evacuation time of increasing the percentage of the ALS fleet available for the evacuation from 5 percent to 10 percent).
  • The dramatic reduction in evacuation time from transporting ALS patients in BLS ambulances (which, of course, raises difficult questions regarding the standard of care).

Return to Contents
Proceed to Next Section


AHRQ Advancing Excellence in Health Care