With the World Trade Center disaster still fresh in our memories, there is ample reason to reassess the state of fire safety in newer buildings where Americans work, live, shop, learn, and play. Why? Because many building codes that establish fire safety standards are based upon the mistaken assumption that sprinklers virtually never fail, and that fire-resistant construction materials can be minimized or eliminated.
Everyone agrees that sprinklers save lives and property. However, the Quincy, MA-based National Fire Protection Association (NFPA) has collected data that shows that sprinklers do not operate approximately 16 percent of the time (see “Voice Your View,” below). This data is based on a 10-year study of more than 8,000 commercial fires in the United States.
Despite the risk of failure, model codes increasingly rely on sprinklers, while reducing requirements for fireproofing, fire-resistant doors, dampers, and other fire and smoke barriers. Municipalities are also considering adopting codes that allow buildings to be constructed taller, wider, and with more open space.
While many view fire barriers as costly excess, emergency responders see them as life-savers. In essence, the more fire- and smoke-resistant construction products that are designed into a sprinklered structure, the less likely it is to collapse during a fire.
Those who doubt the need for fire-resistant construction need only look at the results of the World Trade Center Building Performance Study, which I oversaw in the aftermath of 9/11. This disaster was an extraordinary event involving impact trauma that the buildings’ designers never envisioned and the sprinklers there were overwhelmed. However, the additional fire-resistant construction is believed to have helped reduce the death toll by delaying collapse of the twin towers.
Evidence of the sprinkler systems’ vulnerability in somewhat more conventional fires can be seen in Buildings 5 and 7 of the WTC complex. Both buildings had sprinkler systems. Yet, Building 7 and a portion of Building 5 collapsed from burnout fires. The sprinklers in Building 5 were overwhelmed by the intensity of the fire; and there was insufficient water to combat fire and prevent collapse of Building 7.
Based upon these findings, the fire protection provided by the sprinkler systems alone did not stop the fires in these two buildings. However, the built-in fire protection delayed their collapse, thereby allowing occupants and emergency responders to evacuate both buildings.
Why is this important now? Because two years after 9/11, New York City is gearing up to adopt a new building code – the International Building Code (IBC). At the expense of fire-resistant construction materials, the IBC relies even more extensively on sprinklers than previous model building codes.
The IBC’s requirements for fire-resistant construction are drastically lower than what building codes required two to three decades ago. Consequently, unless the code is amended, I believe occupants, firefighters, and other emergency responders are at a greater risk than ever before.
This issue has implications extending well beyond NYC’s five boroughs. If history holds true, amendments made to the IBC in New York City will be carefully scrutinized by other jurisdictions.
Fire safety cannot be an “either-or” proposition. Buildings with sprinklers should also have fire-resistant construction for better fire protection. Anything less puts occupants and emergency responders at risk, and is, therefore, unacceptable.
Dr. W. Gene Corley, Chicago, is the team leader of the World Trade Center Building Performance Study; senior vice president of Construction Technology Laboratories Inc. (www.c-t-l.com), Skokie, IL; and a consultant for the Philadelphia-based Alliance for Fire Safety.