## The September 11 Context: What the FDNY Faced
The events of September 11, 2001 created conditions that the FDNY had no precedent for managing, even with the department’s long institutional experience and the specific experience of the 1993 World Trade Center bombing, which had required a major rescue and evacuation operation.
The 1993 bombing had been serious — six people killed, over a thousand injured, a major mobilization of the FDNY and other emergency services — but it had not produced structural collapse of the towers. The 2001 attacks were different in kind. The aircraft impacts and the subsequent fires they ignited created structural loads and thermal conditions that the towers’ engineering had not been designed to withstand indefinitely. The South Tower collapsed at 9:59 a.m., 56 minutes after impact. The North Tower collapsed at 10:28 a.m., 102 minutes after impact.
In the interval between the impacts and the collapses, the FDNY mobilized the largest deployment in its history. Companies were called in from across the city. Mutual aid was activated. Hundreds of firefighters entered the towers or were staging in the surrounding area when the collapses occurred. The North Tower collapse trapped many firefighters in the building; the South Tower collapse killed others who were near or in the structure. Some companies were essentially destroyed — losing most or all of their members who had responded to the incident.
The command structure at the site had been dealing with the unprecedented scale of the emergency under conditions of communications failures, physical chaos, and the extraordinary circumstances of two simultaneous major incidents at the same location. After the collapses, the mission shifted from fire suppression and evacuation to search and rescue — and then, as it became clear that the survival rate for people caught in the collapse zones was minimal, to search and recovery. The work of removing the pile continued for months, involving thousands of workers from the FDNY, other city agencies, the military, and a range of civilian contractors.