One Meridian Plaza is a high-rise office building in Philadelphia, Pennsylvania. On February 23, 1991, there was a fire that started in the upper floors of the complex, and this fire is one of the most significant high-rise fires in recent U.S. history. The building consists of 38 floors and sits among several other mid-rise and high rise structures. There are three levels underground and two helicopter landing areas on the rooftop. The building is a steel frame with concrete floors poured over metal decking. All of the structural steel is coated with a spray-on fireproof material. The structural columns are 3-hour fire rated, and the floor and ceiling systems are rated at 2-hours. All of the tenant separation walls and corridors are 1-hour rated. The elevator shafts and stairwells are 2-hour fire rated. Three concrete masonry stairwells service all 38 floors and have standpipes. There are 4 banks of elevators. Separate HVAC and utility shafts run adjacent to the stairwells and have sleeved piping that runs through the fire walls that were not sealed or protected. These unprotected areas create space for fire or smoke travel. The HVAC ducts do not have any fire dampers that penetrate the elevator shaft walls. The fire resistant walls were also penetrated with plumbing that was not sealed or closed and therefore compromised the integrity of the fire resistive walls. The electrical and telephone rooms run from floor to floor and the exposed telephone wiring and electrical conduit also penetrate the walls without being sealed. .
Fire protection devices in this high-rise were inconsistent from floor to floor. During original construction the whole building was outfitted with a coded manual alarm system with manual pull stations near the three stairwells on each floor. The return air ducts and the major air supply ducts had smoke alarms on the two mechanical levels. Hose stations were and portable fire extinguishers were on each floor.