Crowd crushes: how disasters like Itaewon happen, how can they be prevented, and the ‘stampede’ myth
More than 150 people have died in a crowd crush while celebrating Halloween in one of Seoul’s most popular nightlife districts. South Korean authorities have opened an investigation into the disaster. But how do crowd crushes like the one in Itaewon happen?
What happened in Seoul?
On the evening of Saturday 29 October, as many as 100,000 people – mostly in their teens and 20s – poured into Itaewon’s narrow, sloping streets for one of the first major celebrations since Covid restrictions were lifted.
Just after 10pm, chaos erupted on a narrow, steep sidestreet near Itaewon station that connects to a slew of bars and clubs from the main road.
Witnesses reported seeing crowds surging in different directions and people losing their footing on the slope, causing a domino effect.
People fell and knocked others down, piling one person on to another and trapping them. Others tried to scale 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,” crowd behaviour expert at the University of Greenwich, Prof Edwin Galea explains.
This combination of factors – all present in Seoul’s Itaewon district – will lead to a high risk event, Galea says.
If crowd densities rise above four people a square metre, and especially if they get to six, the risk of an accident rises.
A crowd crush occurs whenever too many people push into a confined area – either on the way in, or trying to get out. People can be squeezed to such an extent that they can no longer inflate their lungs, and are at risk of compressive asphyxiation.
Often those who die in crowd crushes are the ones pushed against a wall. No matter how calmly a crowd behaves, it can only fit through a narrow exit at a certain rate.
Related: The deadliest crowd crushes of the last decade
John Drury, an expert on the social psychology of crowd management at the University of Sussex, says crowd crush disasters usually involve three interlinked 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’s apparent that density was over five people per square metre, which is very dangerous. Second, there were waves of people that lifted people off their feet. When people are closely packed together, a small movement can ripple through the crowd and cause further pressure. Third, I understand that there was a crowd collapse as some people fell over and others fell on top of them.”
The layout of the location also didn’t help – “People were walled in on two sides,” Drury adds.
Compounding the problem is that those entering a crowd are oblivious to the impending danger. “Members of the public entering a crowd event can’t see that there might be dangerous levels of density at the front,” he says.
“People often seek out, endure, and enjoy what are objectively dangerous levels of density at many crowd 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 behavioural experiments and mathematical modelling to understand how crowds move in different scenarios. The aim is to prevent dangerous densities from building up.
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 entail lots of simple parts: know the crowd limits, the routes used, the area itself, the movement of the people within it and monitor the crowd density at the time.
Still advises architects, police and event planners on handling large events, and insists that crushes are wholly “preventable, predictable and avoidable”.
Why crowd ‘mass panic’ is a myth
The word “stampede” is often used to describe crowd behaviour. But it’s wrong.
“Stampede is not only an incorrect term, it is a loaded word as it apportions blame to the victims for behaving in an irrational, self-destructive, unthinking and uncaring manner,” Galea says. “It’s pure ignorance, and laziness … It gives the impression that it was a mindless crowd only caring about themselves, and they were prepared to crush people.
“In virtually all these situations this is not the case, and it is usually the authorities to blame for poor planning, poor design, poor control, poor policing and mismanagement.
“The truth is that people are only directly crushed by others who have no choice in the matter, and the people who can choose don’t know what is going on because they’re too far away from the epicentre.”
The language used after these events is often misleading, Drury concurs.
Related: A visual guide to how the Seoul Halloween crowd crush unfolded
For Still, this sort of language shifts the blame and responsibility from the authorities to the crowd.
“At what point did anyone in this crowd think ‘Let’s become a mob’,” he asks. “They didn’t – they reacted to the extreme density and could not escape, leading to a progressive crowd collapse and mass fatalities.
“People don’t die because they panic. They panic because they are dying.”