This Small Business Innovation Research (SBIR) Phase II project will develop new capability to model emergency egress from buildings. The primary focus of the research is evacuation due to fires, but the software will be designed such that exposure and response to biological and chemical agents can also be simulated. The project will couple egress analysis to time-varying fire conditions (e.g. smoke density, heat, and CO) calculated using a Computational Fluid Dynamics fire simulator. This will enable simulation of emergency situations in which, for example, some exit paths become blocked. In addition to incorporating current human response models, the software will allow researchers to specify more complex individual behavior based on the results of recent studies of observed human behavior during emergencies. Thus, the project will not only result in a commercial product of immediate use to the fire safety industry, but will also provide a framework in which to incorporate future knowledge into a problem of fundamental importance to an urban society. This research will lead to a product that will facilitate broad use of fire emergency egress analysis and will introduce a new technology (coupling egress analysis with CFD fire modeling) into the present fire safety design and regulation process. In 2003 fire claimed 3,925 American lives and caused direct losses of $12.3 billion, with a total economic cost of $165 billion. Any technology that reduces even a fraction of this cost will be significant. The integration of egress analysis with fire simulation provides new capability to more accurately simulate emergency building evacuation. The engineering time required for the analyses will be significantly reduced by a common user interface and geometry database that will enable the broader application of this technology throughout the fire safety industry. Societal impacts include increased public safety, advancement in fire research, and reduced building costs. Coupling egress analysis and fire simulation will lead to new discoveries and recommendations based on post accident analysis. The software will enable researchers to add their own models of human behavior to the analysis.