Unthinkable_ Who Survives When Disaster Strikes - and Why - Amanda Ripley [69]
The problem with treating people like water is that water molecules do not experience pain or fear. Water molecules don’t make decisions, and they don’t stumble or fall. Human beings, on the other hand, fill a space unevenly, in clusters. They take shortcuts and pause to rest when they can. Once committed to a path, they don’t easily change course. Groupthink has a momentum of its own.
EXODUS tries to treat people like people. Each evacuee receives a specific age, name, sex, breathing rate, and running speed, among other characteristics. Then EXODUS gives individuals behavioral capacities “so they can make decisions.” For instance, until EXODUS, models assumed that people would begin to evacuate as soon as an alarm went off. Of course, anyone who has ever heard a fire alarm knows this is not what happens. With EXODUS, evacuees have lives and brains. Before leaving, each performs certain tasks—like grabbing a briefcase or searching for a child. And they have the ability to see an exit sign—and follow it—or not. (In experiments with real human beings, Galea has found that many people simply fail to see exit signs, even when they are in plain view. It remains unclear why.)
Most important, the newest version of EXODUS recognizes that people move in groups. That is a difficult behavior to model, which is partly why so few models have ever tried to do it. But it is essential. Galea and his colleagues have analyzed a database of 1,295 survivor accounts from plane accidents. About half of the survivors said they were traveling with someone else at the time of the accident.
EXODUS helped Galea understand that passengers on the Manchester flight had not reacted like synchronized swimmers. Some remained frozen in their seats. Others climbed frantically over seat backs, while still others piled up at an overly narrow exit row, slowing the evacuation to a standstill. One passenger tried to open the exit door beside her, not realizing that she was actually yanking on her armrest. Human behavior, combined with the noxious mix of smoke, heat, and gases, meant that the passengers had very poor odds of getting out.
Today, Galea’s software is used in thirty-five countries. Galea would prefer that it be used before a fire—before a structure is even built. But it is often used as a forensic tool during investigations. The country with the most licenses—and a history shot through with disasters—is Korea. The United States has been “very backward in adopting this kind of technology in the design stage,” he says. “It’s very dangerous.” Before 9/11, most U.S. buildings were constructed without the help of any evacuation modeling at all, he says. Now, models are in vogue, but they vary dramatically in quality. Many of them still treat people like water.
I ask Galea when most architects, engineers, and regulators started taking human behavior seriously. “They’re still not,” he says. “We’re sometimes still told that EXODUS is too complex and has too much human behavior. They want to know, ‘If I have someone here, how long will it take to get out?’ They don’t want to know how they move or if they move in groups. These guys who build buildings don’t want to know about this.”
Smoke Gets in Your Eyes
To get a better idea of what it might feel like to be in a fire, I visited the burn tower at the training academy of the Kansas City Fire Department. Kansas City has just under 450,000 people, and the fire department is the first responder for every emergency call. Each year, Kansas City firefighters respond to nearly sixty thousand requests—or 164 calls a day.
Tommy Walker, the Kansas City Fire Department’s chief of training, insists on picking me up from the airport in a typical display of firefighter hospitality. He is a rail-thin man with a salt-and-pepper mustache and a gee-whiz manner who nevertheless swears like a truck driver. He’s also one of the friendliest, most patient men you’ll ever meet, so it’s a little startling every time he calls someone