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Issues Origin and Cause Fire Alarm System Comments The fire started in a vacant 22nd floor office in a pile of linseed oil-soaked rags left by a contractor. The activation of a smoke detector on the 22nd floor was the first notice of a possible fire. Due to incomplete detector coverage, the fire was already well advanced before the detector was activated. Building Staff Response Building employees did not call the fire department when the alarm was activated. An employee investigating the alarm was trapped when the elevator opened on the fire floor and was rescued when personnel on the ground level activated the manual recall. The Fire Department was not called until the employee had been rescued. Alarm Monitoring Service The private service which monitors the fire alarm system did not call the Fire Department when the alarm was first activated. A call was made to the building to verify that they were aware of the alarm. The building personnel were already checking the alarm at that time. Electrical Systems Installation of the primary and secondary electrical power risers in a common unprotected enclosure resulted in a complete power failure when the fire-damaged conductors shorted to ground. The natural gas powered emergency generator also failed.

Fire Barriers Unprotected penetrations in fire-resistance rated assemblies and the absence of fire dampers in ventilation shafts permitted fire and smoke to spread vertically and horizontally. Ventilation openings in the stairway enclosures permitted smoke to migrate into the stairways, complicating firefighting. Unprotected openings in the enclosure walls of 22nd floor electrical closet permitted the fire to impinge on the primary and secondary electrical power risers.
Standpipe System and Improperly installed standpipe valves Pressure Reducing Valves (PRVs) provided inadequate pressure for fire department hose streams using 1 3/4-inch hose and automatic fog nozzles. Pressure reducing valves were installed to limit standpipe outlet discharge pressures to safe levels. The PRVs were set too low to produce effective hose streams; tools and expertise to adjust the valve settings did not become available until too late.

Locked Stairway Doors For security reasons, stairway doors were locked to prevent reentry except on designated floors. (A building code variance had been granted to approve this arrangement.) This compelled firefighters to use forcible entry tactics to gain access from stairways to floor areas

Exterior Fire Spread “Autoexposure” Exterior vertical fire spread resulted when exterior windows failed. This was a primary means of fire spread.