The Twin Towers: Fire Melting Steel

by Brian Dunning
July 10, 2007

Today we're going to really put the Men in Black under the microscope. And by Men in Black, I mean blacksmiths. You know, those evil government conspirators who expect us to believe that steel can be melted by something that ignites at a far lower temperature. For thousands of years, blacksmiths have been lying to us. They've been telling us that they use coal to melt steel for casting, which, according to a poster on the Skeptalk email discussion list, burns at about 560°F. Fortunately we know better. We don't buy into their lies. We know that steel melts at 2750°F, so we know that these blacksmith shops at local living history museums are all part of the government's master plan of deception. The whole smithing profession and false history was probably invented by the government to prepare us to believe in their biggest lie: That the fires inside the World Trade Center could have brought the towers crashing down.

Conspiracy theorists love to quote retired New York deputy fire chief Vincent Dunn, who said "I have never seen melted steel in a building fire." But they conveniently omit the second half of his sentence: "But I've seen a lot of twisted, warped, bent and sagging steel. What happens is that the steel tries to expand at both ends, but when it can no longer expand, it sags and the surrounding concrete cracks."

One tactic used by conspiracy theorists that has frustrated engineers is their use of a straw man argument, which is where you repeat your opponent's position and carefully reframe it to be weaker and obviously false. Here, the conspiracy theorists have reframed the engineers' position as stating that the World Trade Center fire melted the steel. This is not true, no such claim has been made, as actual melting was neither necessary for the collapse nor possible with the amount of heat that was available.

Let's review the numbers one more time, if you're not already sick of hearing this over the past six years. Steel melts, or liquefies, at 2750°F. Let's take that off the table, because nobody claims that it got that hot, and it wasn't what happened. Jet fuel burns at up to 1500°F. Within about 10 minutes, the jet fuel was exhausted, and the fire then raged among the building itself: its furniture, rugs, curtains, papers, whatever, and temperatures preceding the collapse reached a maximum of 1832°F, according to the National Institute for Standards and Technology's analysis of heat damage to the debris, and as simulated using their computational fluid dynamics model known as the Fire Dynamics Simulator. According to the American Institute of Steel Construction, "Steel loses about 50 percent of its strength at 1100°F, and at 1800°F it is probably less than 10 percent." Even the lowest end of the temperatures inside the fire were way hotter than the hottest temperatures at which the steel trusses could have maintained integrity.

But for the conspiracy theory to work, you have to dismiss any statements made by any official or independent agency, because they could all be part of the conspiracy. The only figures considered reliable are those which differ significantly from official reports. Even expert Rosie O'Donnell told us "It's the first time in history that fire has melted steel."

But then, on April 29, 2007, fire melted steel for the second time in history. A freeway accident occurred in Oakland, California that made us all take a second look. A tanker truck carrying 8,600 gallons of gasoline lost control and crashed on an elevated underpass in the Macarthur Maze, a knot of converging freeway ramps taking cars from the 24, 80, 580, 880, and 980 freeways and funneling them into the San Francisco - Oakland Bay Bridge toll plaza. The fuel exploded into flames and burned fiercely for several hours, but it only took minutes for the span above the flames to collapse and fall onto the span below. The director of Cal Trans, the California state transportation authority, said the heat from the fire had melted the steel girders and bolts that support the concrete roadway. He said "If you have that kind of heat, you're going to have this kind of reaction. We're not surprised this happened."

The massive I-beams built into the structure of the freeway overpasses are far thicker and heavier than the lightweight steel trusses supporting the floors of the World Trade Center. The speedy and graphic nature of this failure demonstrated once and for all how easy it is for heat to soften steel just enough to sag, and that little sag is all it takes for the structure to come apart and then it's Good Night Ladies. In Oakland, these giant beams didn't just sag: they squished like they were made of clay.

Happily, the freeway collapse did have a silver lining. Engineers everywhere breathed a sigh of relief, since this was such a major bitch-slap to the 9/11 conspiracy theorists. Now maybe those nutballs would shut up and go home, right? Maybe even take down their insulting websites. But is that what happened? Don't bet on it. Remember how the logic of the conspiracy theorist works: Evidence against their theory is really evidence for the conspiracy. Within hours, conspiracy theorist blogs and websites were charging that the government staged the Oakland freeway collapse in a transparent attempt to bolster the official version of the World Trade Center events.

Three basic arguments have been made alleging the conspiracy. First, it just seems consistent with what an evil government might do. But, like the majority of the 9/11 conspiracy "evidence", appearing consistent with one possibility in addition to others is hardly proof that that one possibility is the true one.

Second, this fire was outdoors, and not insulated within a building. For some reason the conspiracy guys have turned this one completely around, saying that an uncontained outdoor fire traps heat in better than an enclosed fire. This logic is a little too bizarre for this podcaster to attempt to address. This has nothing to do with oxygen availability, which was the only remotely intelligent extrapolation I could make from this, as the World Trade Center fires were fed not only by airliner sized holes in the side of the building, but also by millions of cubic yards of oxygen inside the buildings.

Finally, the conspiracy guys argue that of all the hundreds of thousands of freeway overpasses in the country, how could this accident just happen to occur at one of the busiest interchanges on the busiest bridge in one of the most traffic congested urban areas in the country? If you wanted to deliberately select the most disruptive and highly visible interchange in the country, this is quite possibly the exact one you'd choose. The two spans that were destroyed carry 160,000 cars a day. What are the chances that this is where such an accident would just happen to occur? Next to impossible. Clearly, this location had to be deliberately chosen. The only possible explanation is that the wreck was staged by the government.

It's kind of hard to argue against that kind of logic. So, I say, don't bother. People who are smart enough to know better, and educated enough to understand the physical sciences, and yet still believe the conspiracy theories, are beyond help. Don't waste your breath on them. And also, don't worry that their fantasies will eventually creep into the history books and infect your children, any more than you should worry that the schools will start teaching the Flat Earth theory. The conspiracy theories are false, so they're unprovable, and all the evidence will always be against them. They're never going to go away, and they're never going to shut up, and as offensive as their paranoid pipe dreams are to civilized people, they have every right to present them and argue their point of view. This is the lesson for your children. Show your children the facts of what happened, and explain why the terrorists did what they did — that's the easy part — and then expand the lesson to the importance of free speech. Better if your children first hear these conspiracy theories within the context of an example of protected free expression of an offensive idea.

That way, your children will be better prepared to visit a blacksmith shop, and know when they're being lied to. ;)

Correction: An earlier version of this used erroneous blacksmith terminology. I said they melt steel for casting. In fact, blacksmiths heat steel to soften it for forging. My apologies to blacksmiths everywhere. —BD

By Brian Dunning
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