...memories, there is ample reason to reassess the state of fire safety in newer buildings where Americans work, live, shop, learn and play," writes Corley.
Schulte and others wonder what an act of war has to do with fire safety in newer buildingsor any buildings. The fires, triggered by the attacks, were significantly larger than fires envisioned by the codes. And the towers' defenses had been "downed" by terrorists, who used hijacked planes as missiles.
Schulte also is rankled by empty rhetoric. During March 6, 2002, congressional hearings on the disaster, Congressman Sherwood Boehlert (R-N.Y.), said that with a greater understanding of buildings, it is possible to "ensure" that "we protect lives in the future" against terrorists.
"Hold on," others chime in. Fires ultimately brought down the towers, by sapping strength from the crippled steel frames. The 47-story Seven WTC, left on its own to burn, collapsed before burnout. That had never happened.
Something must be done to prevent another towering inferno, regardless of the trigger, chorus experts. There are lessons that can be learned from the performance of the WTC, especially as relating to skyscraper fire protection and extreme loads. This is a silver lining to the cloud of 9/11, they say.
Are Schulte and his less vocal supporters right? Are SSCs charges just? Are those blaming the fires for the collapse of the towers soothsayers? Is it acceptable to offer false assurances to calm the public? Is this a case of the tyranny of the traumatized minority or are steel high-rises tinderboxes waiting to become towering infernos, thanks to weak codes and malfeasance on the part of developers? If there are lessons to be gained, is it ethical to sound false alarms to learn them?
Statistics offer perspective, say code experts. According to NFPA, seven civilians died in fires in 1985-1995 in office towers and 633 in high-rise residential buildings (589 in apartments). Yet during the same time period, there were a total of 57,355 civilian deaths in building fires. Few if any high-rise fire deaths were caused by a collapsed structure. Most were caused by smoke and heat.
Fire safety in high-rise buildings is not the problem, says Schulte. "The fire problem" is with one- and two-family dwellings, he says.
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According to Fire Loss in the United States by Michael J. Karter Jr., 68% of civilian fire deaths in 1997-2001, excluding those on 9/11, took place in one- and two-family dwellings. Only 3% occurred in nonresidential structures.
Martin H. Reiss, president and CEO in the Framingham, Mass., office of the RJA Group Inc., a fire and security consultant, says properly enforced codes work. "We see it as business as usual from the fire point of view," he says.
If anything, Reiss fears not enough attention is being focused on how heightened, post-9/11 building security clashes with fire safety. Jersey barriers impede fire trucks and locked doors and security checkpoints impede egress, he says.
Joseph Caprile, a principal of Lohan, Caprile Goettsch Architects, Chicago, agrees that model codes are adequate. He says the problem in some cities is that adopted codes are antiquated and that many are not retroactive.
Solomon agrees codes work in a pre-9/11 world. But the burning question is "whether they work for the newer hazards on everyones radar screen," he says.
Still, the fire engineering sector does not want massive code reform without research, says Solomon. "Do you change the code for a one in 30-year event or a one in 50-year event?" he asks. "Prior to 2001, the answer was no."
Once there is an understanding of how realistic it is to design for new hazard scenarios, or hostile acts, the codes will have to be evaluated and probably modified, says Solomon. Toward that end, NFPA formed a high-rise advisory committee with members from the public, first responders and professional groups.
One thing is incontrovertiblethe tower collapses stoked longstanding feuds and ignited debates. It remains automatic sprinklers pitted against passive resistance, concrete versus steel, and there are ongoing concerns with ASTME119, the materials test for fire ratings.
For designers, it is a question of the feasibility of designing structures to remain standing after burnout and the necessity of considering fire as a structural load (see p. 50). There also is a continuing debate about performance-based design and the need to address progressive or "disproportionate" collapse.
Some experts are pushing a multihazard design approacha method that considers seismic, wind and fire loads together to achieve the best performance in extreme events. "Our approach to all hazards needs to be consistent, which would include a probabilistic and complimentary approach so that we dont find ourselves overcompensating for the hazard du jour," says Tom Z. Scarangello, a managing principal of Thornton-Tomasetti Engineers, New York City. "If changes are not addressed as part of a multihazard mitigation-based philosophy, we are missing the boat," he says.
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On the practice side, there is discussion about the roles of different professionals. Some fire protection engineers are suggesting a new service to architects and owners that would combine fire and structural engineering.
There is still a stairwell-width debate, issues about retroactive code compliance and a controversy over using masonry or fire-rated gypsum board for stair enclosures. Code officials also are considering whether there needs to be special fire protection and security provisions for landmark and tall buildings and adjacent properties. Last month, for example, the International Code Council, a model codewriter, voted to eliminate allowable reductions in passive containment for buildings more than 420 ft tall that have sprinklers.
There are less controversial subjects. Mechanical engineers are weighing the merits of dedicated elevators for firefighters and using elevators for evacuation. There also is talk of pressurized stairwells and refuge floors.
NFPA may think more research is needed to resolve these issues, but Schulte does not. He especially opposes the $16-million WTCBuilding and Fire Safety Investigation, concluding this fall, by the National Institute of Standards and Technology. Schulte is on a mission to expose NIST and its contractors as having jumped on NISTs post-9/11 gravy train, he says.
"The implementation of the results of [a WTC] investigation would be critical to restore public confidence in the safety of tall buildings nationwide and better protect...
