A Times investigation shows how a New York City high-rise became a deadly chimney of smoke.
How stairwells became chimneys
Twin Parks North West, an affordable-housing building constructed in 1972, is like many older residential high-rises in New York City that have minimal or no sprinklers in place: It relies primarily on compartmentation to keep smoke from spreading in case of a fire. That means doors must automatically close and latch after someone passes through. If the doors close, the smoke is largely contained. If not, residents are at risk of severe injury or death by smoke inhalation.
At Twin Parks North West, compartmentation broke down in at least three places on Jan. 9. Not only did the door to Apt. 3N, where the fire began, stay open, so did both doors to the third-floor stairwells for lengthy periods. Doors to stairwells in at least two higher floors also malfunctioned, allowing smoke to permeate the building.
“You have a gross failure of compartmentation, because there is smoke everywhere in a few minutes,” said Jose L. Torero, a professor at University College London who has investigated major fires including at the World Trade Center on Sept. 11 and Grenfell Tower in Britain in 2017.
There is certain to be considerable debate — technical, political and legal — over who was responsible for so many doors being partially or completely open when their closure could have saved lives. Maintenance of the doors and the actions of building personnel and some tenants are likely to come under scrutiny.
Using evidence The Times obtained and a 3-D model of the building The Times created, a team led by Albert Simeoni, head of the fire protection engineering department at Worcester Polytechnic Institute in Massachusetts, created a simulation of the smoke’s path on Jan. 9. The simulation was for hallways, stairwells and the apartment where the fire started — the main conduits for smoke — but not for individual apartments in the building, where information on door openings was limited.
Calls for help
The most direct indication of how swiftly the smoke moved through the building is also the most heartbreaking: calls to 911 from residents trapped in their apartments, struggling to breathe, some of them with children, pleading for help, guidance and information.
Within 10 minutes of the first 911 call, smoke was already reported on the 16th floor. Calls were made from more than 40 of the 120 apartments.
As the city waits for the results of an official investigation, the scale of the disaster is unquestioned. “The Twin Parks fire is one of the worst in our city’s history,” said Laura Kavanagh, the acting fire commissioner, “with innocent lives taken from a deadly combination of a space-heater fire and open doors on multiple floors that allowed smoke to spread throughout the building.”
The investigation is likely to center around the self-closing doors. In interviews with The Times, Mr. Yolles, the spokesman for the building’s ownership group, and a city official said that when residents fled, the 3N door remained stuck open, possibly from an extra layer of flooring, though it’s unclear whether it was thick enough to make a difference. A lawyer representing the Wagues said there would be no comment from the family at this time.
Reliant Realty Services, the management company, said in a statement that the 3N door “was signed off as working properly” after an inspection last year, and that the Fire Department and building tenants were primarily to blame. “The third-floor doors were opened multiple times during the fire by residents and the F.D.N.Y. for firefighting operations, which caused smoke to fill the stairwells and reach the upper floors,” the company said.
The Reliant claims are difficult to square with visual evidence from security camera footage. This evidence has not been released publicly, but a city official described it to The Times. The official said the footage showed that a third-floor stairwell door never latched after a building worker opened it and that a 15th-floor stairwell door became stuck after a tenant opened it earlier.
“To be very clear, prior to F.D.N.Y. arrival at this fire, the third floor, stairwell and multiple upper floors were filled with thick, choking smoke due to multiple open doors throughout the building,” said James Long, a spokesman for the New York Fire Department. “To state that firefighters bravely working to save the lives of residents are the cause of the smoke reaching upper floors is insulting and a gross deflection of responsibility,” he said.
More modern high-rises in the city, or older ones that have been retrofitted, have numerous additional safety features, including sprinklers and fire alarms connected to “central stations,” and from there to firehouses. At Twin Parks North West, there was an alarm system, but it was not connected to fire stations, which the building’s owners confirmed.
Mr. Yolles, the spokesman for the building owners, said that, when the building was constructed, the system was consistent with the New York State code, and that the owners plan to upgrade it.
Additional protective measures provide “redundancies,” or backups in case another safety feature fails, said Jonathan Barnett, a fire safety expert who investigated the World Trade Center fires of Sept. 11 and has been a consultant on the official investigation into the 2017 Grenfell Tower fire in London. “The point is that if you’re going to rely on one system and one system only, you’d better make sure it works,” he said.
The 3-D model of the building is based on architectural drawings from the New York City Department of Buildings. The Times reviewed design and planning documents and inspected portions of the building in person, including one of the two stairwells, after the fire.
To better understand how the catastrophe unfolded, The Times spoke with residents about what they witnessed on Jan. 9 and about the conditions on many floors of the building before and during the fire. Times reporters reviewed photos and videos taken by residents during the fire and the evacuation as well as those officials took later. The Times also examined video that witnesses captured and uploaded to Citizen, an app that allowed people nearby to document the minute-by-minute progression of the fire. Through a Freedom of Information Law request, Times reporters obtained audio logs of 911 calls made by the residents the morning of the fire. To verify which apartments the calls were made from and when they occurred, we synced the 911 calls with the dispatch report of the fire obtained by the New York Police Department.
The Times asked scientists at Worcester Polytechnic Institute in Massachusetts to conduct numerous simulations to help explain how smoke could have raced so freely through the building. The simulations were led by Albert Simeoni, professor and head of the department of fire protection engineering, and carried out by Muthu Kumaran Selvaraj, a postdoctoral researcher in the department. The simulations were created using software called Fire Dynamics Simulator, developed by the National Institute of Standards and Technology and used widely by researchers and investigators to estimate the flow of smoke in structures.
Times reporting and public information from the New York Fire Department informed boundary conditions and other inputs for the simulation. These included the starting point and overall progression of the fire; the times when windows broke; and whether specific doors were open, closed or simply not functioning properly — including the opening of stairwell doors on the third, 15th and 19th floors. These inputs also included firsthand observations of the stairwells, which helped us determine, for example, that the stairwells had no pressurization or smoke-extraction systems to mitigate smoke flow. Many different scenarios were run in order to determine the influence of the opening or closing of particular doors, precisely how the fire progressed and other conditions in the building.
The simulations used ventilation calculations based on the 1964 New York State building code. Twin Parks North West was built in 1972. After consulting fire safety experts, we decided on a method to determine how long the stairwell doors were open purely for egress on each floor. We used a conservative estimate of the few seconds during which a properly functioning door would be open for each resident to be able to exit.
Where exact information on conditions inside the building were not available, some approximations were made based on reasonable estimates drawn from video observations, photographic evidence, descriptions contained in calls to 911, interviews with residents and city officials and public statements by Fire Department officials. For example, heavy smoke emanating from a few windows indicated that there was a path for smoke and air to flow from an interior hallway to the outside. Because the details of that path are not known, the simulation approximated the flow.
Sources: Jose L. Torero, University College London; Albert Simeoni, Worcester Polytechnic Institute; Muthu Kumaran Selvaraj, Worcester Polytechnic Institute; Charles Jennings, John Jay College of Criminal Justice; Philip J. Landrigan, Program for Global Public Health and the Common Good at Boston College; Robyn Gershon, New York University; Brian Meacham, Meacham Associates; Jonathan Barnett, Basic Expert; Jack J. Murphy, John Jay College of Criminal Justice; Gregory A. James, JB&B; Rainald Lohner, George Mason University; Bryan Klein, Thunderhead Engineering; New York City Department of Buildings; New York Police Department; New York Fire Department