Rescue and recovery effort after the September 11 attacks

The local, state, federal and global reaction to the September 11 attacks on the World Trade Center was unprecedented. The equally unsurpassed events of that day elicited the largest response of local emergency and rescue personnel to assist in the evacuation of the two towers and also contributed to the largest loss of the same personnel when the towers collapsed. After the attacks, the media termed the World Trade Center site "Ground Zero", while rescue personnel referred to it as "the Pile".

In the ensuing recovery and cleanup efforts, personnel related to metalwork and construction professions would descend on the site to offer their services and remained until the site was cleared in May 2002. In the years since, investigations and studies have examined effects upon those who participated, noting a variety of afflictions attributed to the debris and stress.

After American Airlines Flight 11 crashed into the North Tower (1 WTC) of the World Trade Center, a standard announcement was given to tenants in the South Tower (2 WTC) to stay put and that the building was secure. However, many defied those instructions and proceeded to evacuate the South Tower (most notably, Rick Rescorla, Morgan Stanley Security Director, evacuated 2687 of the 2700 Morgan Stanley employees in the building). All people evacuating were ordered through a door on the mezzanine level that led to a bridge to another building, and everyone was evacuated through the neighboring building. The firefighters in charge did not want anyone going through the front doors at first due to falling debris, and then because of falling people who had jumped from the towers.

Standard evacuation procedures for fires in the World Trade Center called for evacuating only the floors immediately above and below the fire, as simultaneous evacuation of up to 50,000 workers would be chaotic.

Firefighters from the New York City Fire Department rushed to the World Trade Center minutes after the first plane struck the north tower. Chief Joseph Pfeifer and his crew with Battalion 1 were among the first on the scene. At 8:50 a.m., an Incident Command Post was established in the lobby of the North Tower. By 9:00 a.m., shortly before United Airlines Flight 175 hit the South Tower, the FDNY chief had arrived and took over command of the response operations. Due to falling debris and safety concerns, he moved the incident command center to a spot located across West Street, but numerous fire chiefs remained in the lobby which continued to serve as an operations post where alarms, elevators, communications systems, and other equipment were operated. The initial response by the FDNY was on rescue and evacuation of building occupants, which involved sending firefighters up to assist people that were trapped in elevators and elsewhere. Firefighters were also required to ensure all floors were completely evacuated.

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