November 16, 2022

One Meridian Plaza – High Rise Fire Protection

The date is February 23, 1991, it’s about 8:20pm. It’s the middle of winter, everything is frozen to the earth. The smell of smoke is filling the air in downtown Philadelphia. If you were to be standing inside the lobby of One Meridian Plaza, you hear the sounds of a fire alarm activation. What transpires next will set the stage for changes to the fire protection industry and how firefighters operate in a high-rise fire for years to come. On that historic day of February 23, 1991, the Philadelphia Fire Department endured one of the worst calls to service they have ever had to deal with. One Meridian Plaza was a 38 story, 492-foot commercial high-rise that was built in 1973. At the time the building was constructed, fire sprinklers were not code to be required in a high-rise in the city of Philadelphia. The fire broke out on the incomplete and under construction 22nd floor. A contractor was using linseed-soaked rags on a Friday afternoon for a renovation project. Firefighters are trained when using a linseed-soaked rag, once the work is complete, to store the soaked rag in a metal container with a lid, otherwise the rag will spontaneously combust. In the case of the One Meridian fire, the contractor failed to dispose of his linseed-soaked rags properly, thus sparking the blaze that consumed eight floors of the building.


At the time of the incident the fire alarm coverage was incomplete and only in the HVAC system at the opposite side of the 22nd floor from where the fire started. This caused a significant delay in response and allowed the fire to grow outside the early stages of development. Once the smoke finally found the detector, the alarm sounded. The building staff consisted of two security personal and a building engineer that cold night of February 23rd. When the alarm came over, the building security had the building engineer go up to the 22 floor to investigate the alarm. The Philadelphia Fire Department was yet to be notified of the alarm. Shortly after the building engineer left the lobby for the 22nd floor to investigate the alarm, the alarm monitoring service called the building security staff, not the Philadelphia Fire Department. Once the building engineer reached the 22nd floor, the elevator car doors slid open revealing a fully evolved environment of fire. The engineer was forced to the floor of the elevator car because of the intense heat. It was so hot he couldn’t reach the buttons to close the doors to get himself back down to the lobby. Luckily the engineer used his radio and had the building security manually recall the elevator thus savings the engineer from the approaching fire.


If something could go wrong that February 23rd night, it did. Once the engineer was back in the elevator car and returning to the lobby, the buildings power was compromised which now added to the workload of the fire department because the engineer was now an elevator rescue. The high-rise fire that night was able to grow rapidly for a variety of reasons. Fire barriers were incomplete allowing the fire to spread both vertically and horizontally as well as through autoexposure. Autoexposure meaning the fire heated the windows to the point of failure, then blew out the windows heating up the windows on the floor above and so on.


In addition to incomplete fire barriers and autoexposure, the fire department had an even harder fight on their hands which was trying to get water on the fire. One Meridian had new technology called pressure reducing valves (PRV) on the standpipes in the building. A PRV reduces the pressure at the standpipe connection that is coming from the fire pump. In this case, the new to the market PRV’s were preset to 65 pounds per square inch (PSI). This pressure is a fraction of what is needed for a fire hose to operate properly thus creating a major issue for the firefighters to get enough water out of the hoses to fight the fire. Lastly all the stairway doors were locked and made from metal which made it very difficult to gain entry by the firefighters.


The One Meridian Plaza fire burned for 19 hours, killed three firefighters, and completely consumed 8 floors of the building before it was halted by ten activated fire sprinkler heads on the 30th floor. Although it was not code to have fire sprinklers, the 30th floor tenant was Cablevision, and their belief was fire sprinklers are essential to protect their employees. In 1999, the One Meridian Building was ultimately demolished piece by piece.


The One Meridian Fire sparked a surge of changes from the fire protection community because of a multitude of un-wanted outcomes. The first two significant noteworthy changes came from the NFPA. The NFPA made a change to the NFPA 14 code which mandates a minimum residual pressure of 100 psi at any 2 ½” standpipe outlet and requires that pressure-reducing valves be used anytime an outlet pressure to a hose connection is greater than 175 psi. In addition, the NFPA changed their stance on automatic or constant-pressure nozzles are not recommended for use on automatic standpipes. The NFPA stated “potential low system pressures insufficient to supply the required nozzle pressure can cause the nozzle orifice to constrict, which greatly reduces the flow and reach of the hose line.” The last big change came from the city of Philadelphia directly who made it code for all commercial high-rise buildings to be fully fire sprinklered. This change took roughly four years to accomplish.


As of today, all commercial buildings greater than 75 feet tall in the city of Philadelphia are fully fire sprinklered. The National Fire Sprinkler Association, PenJerDel Chapter in lock step with the Fire Sprinkler Fitters Local Union 692 and the governing body of Philadelphia are planning on doing a fire sprinkler live fire burn demonstration on the footsteps of city hall on November 10th, 2022. The hope is to bring attention to the importance of fire sprinklers and the need for them in residential high rises in the city of Philadelphia.  Fire is fast, but water is faster. Fire sprinklers buy time and time buys life.


November 16, 2022

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