Photograph: YONHAP / Reuters
More than 150 people died in the crowd while celebrating Halloween in one of Seoul’s most popular nightlife districts. South Korean authorities have opened an investigation into the disaster. But how can crowd dunks like Itaewon’s happen?
What happened in Seoul?
On the evening of Saturday 29 October, as many as 100,000 people – mostly teens and 20s – poured into Itaewon’s narrow, sloping streets for one of the first big celebrations since Covid restrictions were lifted.
Just after 10pm, chaos erupted on a narrow, steep lane near Itaewon Station that connects to a slew of bars and clubs from the main road.
Witnesses reported seeing crowds rising in different directions and people losing their balance on the slope, causing a domino effect.
People fell and threw others to the ground, piling one person on top of the other and trapping them. Others tried to climb the sides of the buildings to escape.
What is a crowd crush?
“Overcrowding, unmanaged crowds and wide paths filtering into narrow paths are a recipe for disaster,” explains Professor Edwin Galea, an expert on crowd behavior at the University of Greenwich.
This combination of factors, all present in Seoul’s Itaewon district, will lead to a high-risk event, says Galea.
If the density of the crowd exceeds four people per square meter, and especially if it reaches six, the risk of accidents increases.
A crowd dunk occurs whenever too many people push themselves into a confined area, either while entering or trying to get out. People can be squeezed to the point where they can no longer inflate their lungs and are at risk of compression asphyxiation.
Often those who die in a crowd are the ones pushed against a wall. No matter how calmly a crowd behaves, it can only pass through a narrow exit at a certain speed.
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John Drury, an expert in the social psychology of crowd management at the University of Sussex, says crowd crush disasters usually involve three interrelated factors: overcrowding, waves or movement in an already extremely dense crowd, and crowd collapse. When there is an obstruction, the effects are exacerbated.
“My impression is that all of these factors were present at Itaewon this Halloween,” he says. “First, it is clear that the density was over five people per square meter, which is very dangerous. Secondly, there have been waves of people lifting people off their feet. When people are crowded together, a little movement can ripple in the crowd and cause additional pressure. Third, I understand that there was a collapse of the crowd when some people fell and others fell on top of them. “
The layout of the location didn’t help either: “People were bricked up on two sides,” Drury adds.
Compounding the problem is that those who enter a crowd are oblivious to the impending danger. “Members of the public attending a mass event cannot see that there could be dangerous levels of density at the front,” she says.
“People often seek, endure and appreciate what are objectively dangerous levels of density in many mass events,” Drury adds.
How can these disasters be prevented?
Crowd management for large-scale planned events is essential, experts agree.
Galea and his fire safety engineering group at the University of Greenwich use behavioral experiments and mathematical models to understand how crowds move in different scenarios. The goal is to prevent the accumulation of dangerous densities.
Crowd safety isn’t complicated, according to G Keith Still, a crowd safety expert and visiting professor of crowd science at the University of Suffolk in England.
A management plan can include many simple parts: knowing the crowd limits, the routes used, the area itself, the movement of people within it, and monitoring the crowd density at that time.
Still advises architects, police and event planners on managing large events and insists that crushes are completely “preventable, predictable and avoidable”.
Because the “mass panic” of the crowd is a myth
The word “stampede” is often used to describe crowd behavior. But that’s wrong.
“Stampede isn’t just a misspelled term, it’s a charged word as it blames victims for behaving irrationally, self-destructively, recklessly and indifferently,” says Galea. “It’s pure ignorance and laziness… It gives the impression that it was a mindless crowd that only cared about itself and was ready to crush people.
“In virtually all of these situations this is not the case, and it is usually the fault of the authorities for poor planning, poor design, poor control, poor policing and poor management.
“The truth is that people are directly crushed by others who have no choice in the matter, and the people who can choose do not know what is happening because they are too far from the epicenter.”
The language used after these events is often misleading, Drury agrees.
Related: A visual guide to how Seoul’s throng of Halloween crowds unfolded
For Still, this type of language shifts the blame and responsibility from the authorities to the crowd.
“At what point did someone in this crowd think ‘Let’s become a crowd’,” he asks. “They didn’t – they reacted to the extreme density and failed to escape, leading to a progressive crowd collapse and mass casualties.
“People don’t die because they panic. They panic because they are dying. “