Sprinklers just the start in keeping buildings safe from fire
By Dr. W. Gene Corley, Senior Vice President, Construction Technology
Laboratories, Skokie, IL; Team Leader, World Trade Center Building
As we approach the second anniversary of the World Trade Center
disaster, 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,
therefore, be minimized or eliminated.
Virtually everyone agrees that sprinklers save lives and property.
However, the National Fire Protection Association, a fire safety
watchdog group, has collected data that show that sprinklers do
not operate approximately 16 percent of the time. The figure is
based on a 10-year study of more than 8,000 commercial and industrial
fires in the United States.
Despite the risk of failure, there is a trend for model codes to
rely increasingly on sprinklers, while reducing requirements for
fireproofing, fire-resistant doors, dampers and other fire and smoke
barriers. At the same time, municipalities are considering adopting
codes that allow buildings to be constructed taller and wider, with
more open, flexible space.
While many view fire barriers as costly excess, firefighters and
other 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 that
it will 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. While the World
Trade Center disaster was an extraordinary event involving impact
trauma that the buildings' designers never envisioned, 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 vulnerability of sprinkler systems in somewhat
more conventional fires can be seen in Buildings 5 and 7 of the
World Trade Center complex. Building 7 is not believed to have been
seriously impacted by the collapse of the towers; Building 5 did
have some severe damage from falling debris, but much of the building
was undamaged. 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 either no water supply or insufficient water
to combat fire and prevent collapse of Building 7.
Based upon these findings, it is clear that the fire protection
provided by the sprinkler systems alone did not stop the fires.
However, the built-in fire protection delayed their collapse, allowing
occupants and emergency responders to evacuate both buildings.
Why is this important now? Because almost precisely two years after
9/11, New York City is gearing up to adopt a new building code--the
International Building Code. Regrettably, the new code relies even
more extensively on sprinklers at the expense of fire-resistant
In fact, the international building code's requirements for fire-resistant
construction are drastically lower than what building codes required
two to three decades ago. In addition, it allows buildings to have
more stories, more open space, narrower stairwells, longer distances
to an exit, and fewer exits than is permissible under other codes.
Consequently, unless the code is amended, it will place occupants,
firefighters and other emergency responders at greater risk than
The issue has implications extending well beyond the city's five
boroughs. If history holds true, amendments made to the international
building code in New York City will be carefully scrutinized by
other jurisdictions across the country.
Fire safety cannot be an ''either-or'' proposition. Buildings for
which sprinklers are appropriate should also have fire-resistant
construction for better fire protection. Anything less puts occupants
and emergency responders at risk, and is, therefore, unacceptable.