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The Towering Inferno of fiction became a reality for the tallest building in Los Angeles in May 1988. Starting on the 12th floor , an after-hours fire destroyed five floors of the 62-story First Interstate Tower, killing one, injuring 40. A sprinkler system was being installed at the time. |
Continued from page 1 So guess which one the firefighters like to fight the fires in the most. Well, you guessed it, the heavyweights. Not because we're hopeless romantics in love with the architecture of the early 20th Century. Why then? Because they perform under stress. You see, we are interested in results. It's all fine and well that a particular partition is supposed last against a fire X amount of hours in a controlled laboratory test, or that a curtain wall is not supposed to allow fire to pass from one floor of a high-rise to the next. But in the organized chaos of firefighting, the knuckle dragging grunt work, the 100 or more variables thrown into the mix, the controlled yelling to orchestrate men into action against the Red Devil, the race against time, the sheer physical logisticsÉ they don't usually do what they were designed to do. Now in the case of the Trade Center, it did do what it was supposed to do: collapse pancake-style to avoid toppling and taking out the other 20 or 30 square blocks surrounding it. This is all Monday morning quarterback stuff for us because we've never had a major unplanned collapse of a multi-story high-rise, and would not have planned for one either until now. Since they survived the blast in 1993, there is no way you could have convinced me and probably a lot of other people that the buildings were ever coming down. Traditionally we are all about saving lives first then property. We take it personally when we lose buildings, big time, to a fire. Overachieving bastards that we are, individuals with in the Fire Department will probably start going out and identifying any remaining buildings built in the style of the WTC, and buildings that remain potential terrorist targets, and buildings in general that we stare at and say, "Gee, I hope I never get a fire in that building," because we know it will have its share of logistical nightmares. A few digital cameras and a few Power Point projectors and we'll do wonders. That's our end of it, "Be prepared." They aren't going to change the existing buildings out there. Hell, we knew in the Fire Service that we didn't like trusses before September 11, thanks to Vincent Dunn, who wrote Collapse of Burning Buildings : A Guide to Fireground Safety, among others, and Francis Brannigan, author of Building Construction for the Fire Service. We didn't know how extensive those trusses were in the Trade Center, and it wouldn't have mattered much anyway. You see, to us there were possibly 50,000 people in need of rescue and we had a job to do. Engineers love trusses. Load-carrying ability ratio to their relative weight is fantastic. They're relatively inexpensive, span greater distancesÉ what's not to like? How about no fire resistive rating? That's right none, zero, bupkus. Spray on fireproofing, you say? You mean the stuff that looks like popcorn made of mineral fiber? Or in the case of the Trade Center, asbestos that flakes off with your fingers? Maybe in a regular office fire, but not in an explosion or being hit with a Boeing 767. No way was that stuff staying on. Look, I've seen an 18 inch I-beam with spray-on fireproofing in an acetylene-fueled fire and metal bar joists with the same in an ordinary office fire. I know which one I would rather hang around under. Oversimplifying again, the way we understand it right now is that fire resistance is directly a function of the mass of the components of the building. The more mass, the more fire resistance. The heavier the weight, the better. Another dilemma. See, the Empire State Building has survived numerous fires and even had a plane—a smaller one than a 767—crash into it without terrible structural damage, while in 30 years the Trade Center had no major fire whatsoever. Now, the Fire Safety wasn't vastly superior at the WTC, so what gives? Maybe the prescence of sprinklers in one and not the other? Sprinklers are the best defense we have right now against fire. The large-scale devastation of September 11 relagates sprinklers to little importance. Technology employed in the Petronas Towers in Kuala Lumpur, Malaysia, where a central core of high strength concrete is employed as "spine," protecting the elevators, stairs, utilities and other vitals is a step in the right direction. Stairwells protected by concrete and steel instead of sheetrock would have resulted in lower casualities at the WTC. Walls were obliterated and doorjambs jammed as the building settled into its death throes, barring escape for many. What if power remained on and the elevators stayed operational? Highrise buildings in New York built between 1945 and 1968 were required to have a "fire tower," a stair in a shaft open at top and separated from the floor space by a vestibule with two doors at each end. This is a tremendous advantage to fleeing occupants psychologically(fresh air) as well as physically. The problem for the Fire Service is identifying these stairwells and using them for evacuation only. You see, we can't use these for stretching the primary attack hose line, because once we open all the doors, we have just completed the giant chimney and were stuck in it like errant raccoons who wandered into a residential fireplace chimney. Most stairwells that aren't of the Fire tower type are pressurized to limit smoke and heat travel. So we've got sprinklers, dedicated evacuation stairs, elevators, all protected from the effects of anything short of nuclear blast. Also, we left out fire loads. When engineers figure out a building's stresses, wind load, floor load, dead load, impact load, live loads, static loadsÉ is fire figured in? Space age materials? New technologies? Bring it on. We're not Luddites in the Fire service. Bring them on, but on one condition, let us set the fire to test them, or better yet the NFPA, using previous horrible fires and all their variables to set the test parameters. I mean, if we are going to design all these specs for safety and then load the building with plastics and its derivatives—basically long-chain hydrocarbons a few C's or H's in their molecular structure short of being gasoline—then we might as well forget it. Page
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