Design Fires and Actions

This chapter addresses design fires in the context of structural fire safety. First, the design fuel load must be derived for the given space, which represents the potential energy that needs to be considered. Once the design fuel load is established, estimation of the fire exposure intensity on the structure is a key next step in the process. Specifically, thermal boundary conditions acting on structural and/or insulative exposed boundaries must be derived so that subsequent heat transfer analyses may be conducted to determine the temperature histories of the given structural system. Structural fire engineering designs typically only consider a subset of design fires, which are those that are uncontrolled (any cooling effects of active fire protection systems and/or manual intervention are neglected). Other design fires (e.g. those used for determining the available safe escape time) would not commonly be used for SFE applications. Accordingly, fire dynamics concepts pertaining to uncontrolled fire exposures are presented in this chapter.