Four firefighters died when a floor collapsed without warning during a commercial building fire in downtown Seattle on January 5,1995. The cause of the fire was determined to be arson, and a suspect was apprehended and charged with four counts of homicide. The circumstances of this incident are similar to a number of other multiple fatality incidents that have claimed the lives of more than 20 firefighters in recent memory across the nation.1 The similarities include fires in buildings that have access at different levels from different sides, resulting in confusion over the levels where companies are operating. There have also been a number of situations where firefighters have been operating on a floor level that appeared to be safe, not knowing that they were directly above a serious basement or lower level fire. These incidents resulted in sudden and unanticipated floor collapses, which either dropped the firefighters into the fire area or exposed them to an eruption of fire from the level below them.