The crowd deaths at a Houston music festival added even more names to the long list of people who have been crushed at a major event.
Tragedies like the one Friday night at the Astroland Music Festival have been happening for a long time. In 1979, 11 people died in a scramble to enter a Cincinnati, Ohio, concert by The Who. At the Hillsborough soccer stadium in England, a human crush in 1989 led to nearly 100 deaths. In 2015, a collision of two crowds at the hajj pilgrimage in Saudi Arabia caused more than 2,400 deaths, based on an Associated Press count of media reports and officials' comments.
Now that more people are heading out of their homes and back into crowds after many months of being cooped up because of the pandemic, the risks are rising again.
Most major events happen without a death, of course, but experts say they see common traits within the tragedies. Here's a look at how they happen:
HOW ARE PEOPLE DYING IN THESE EVENTS?
They're often getting squeezed so hard that they can't get any oxygen. It's usually not because they're getting trampled.
When a crowd surges, the force can be strong enough to bend steel. It can also hit people from two directions: one from the rear of the crowd pushing forward and another from the front of the crowd trying to escape. If some people have fallen, causing a pileup, pressure can even come from above. Caught in the middle are people's lungs.
WHAT'S IT LIKE TO BE SWEPT IN?
A UK inquiry into the Hillsborough tragedy found that a form of asphyxiation was listed as an underlying cause in the vast majority of the deaths. Other listed causes included "inhalation of stomach contents."
The deaths occurred as more than 50,000 fans streamed into the stadium for a soccer match on a warm, sunny day. Some of them packed into a tunnel and were getting pressed so hard into perimeter fencing that their faces got distorted by the mesh, the inquiry found.
"Survivors described being gradually compressed, unable to move, their heads 'locked between arms and shoulders ... faces gasping in panic,'" the report said. "They were aware that people were dying and they were helpless to save themselves."
WHAT CAUSES SUCH EVENTS?
"My research covers over 100 years of disasters, and invariably they all come down to very similar characteristics," said G. Keith Still, a visiting professor of crowd science at the University of Suffolk in England who has testified as an expert witness in court cases involving crowds.
First is the design of the event, including making sure that the density of the crowd doesn't exceed guidelines set by the National Fire Protection Association and others. That includes having enough space for everyone and large enough gaps for people to move about.
Some venues will take precautions when they know a particularly high-energy crowd is coming to an event. Still pointed to how some will set up pens around stages in order to break large crowds into smaller groups. That can also allow for pathways for security officers or for emergency exits.
WHAT ARE OTHER CAUSES?
The crowd's density may be the most important factor in a deadly surge, but it usually needs a catalyst to get everyone rushing in the same direction.
A sudden downpour of rain or hail could send everyone running for cover, as was the case when 93 soccer fans in Nepal were killed while surging toward locked stadium exits in 1988. Or, in an example that Still said is much more common in the United States than other countries, someone yells, "He has a gun!"
Surges don't always happen because people are running away from something. Sometimes they're caused by a crowd moving toward something, such as a performer on the stage, before they hit a barrier.
Still also cited poor crowd-management systems, where event organisers don't have strong procedures in place to report red flags or warnings, among the reasons deadly surges happen.
HOW HAS THE PANDEMIC AFFECTED THINGS?
Steve Allen of Crowd Safety, a UK-based consultancy engaged in major events around the world, said it's always important to monitor the crowd, but especially so now that events are ramping up in size following the pandemic lockdown.
"As soon as you add people into the mix, there will always be a risk," he said of crowds.
He recommends that events have trained crowd spotters with noise-cancelling headsets who are in direct communication with someone in close proximity to the performer who's willing to temporarily stop the event if there's a life-threatening situation. That could be a crowd surge, structural collapse, fire or something else.
Allen said he has personally stopped about 25 performances by the likes of Oasis, the Red Hot Chili Peppers and Eminem.
WHY AREN'T PEOPLE CALLING THIS A STAMPEDE?
Professionals don't use the words "stampede" or "panic" to describe such scenarios because that can put the blame for the deaths on the people in the crowd. Instead, they more often point at the event's organisers for failing to provide a safe environment.
"Safety has no profit," Still said, "so it tends to be the last thing in the budget."
Fans at a Houston music festival surged toward the stage during a performance by rapper Travis Scott, triggering panic in the crowd and leaving at least eight people dead and many more injured, authorities said. Here's a look at some of the major crowd disasters in recent decades:
December 3, 1979 — Eleven people are killed as thousands of fans rush to get into a concert by The Who at Riverfront Coliseum in Cincinnati.
October 20, 1982 — Sixty-six people die in a crush of fans leaving a Uefa Cup match between Spartak Moscow and Haarlem, of the Netherlands, at Luzhniki Stadium in Moscow.
May 28, 1985 — Thirty-nine people died in fan violence at the 1985 European Cup final between Liverpool and Juventus at Heysel Stadium in Brussels.
March 13, 1988 — Ninety-three people are killed when thousands of soccer fans surge into locked stadium exits to escape a sudden hailstorm in Kathmandu, Nepal.
April 15, 1989 — Ninety-seven people die and hundreds are injured in a crush of fans at overcrowded Hillsborough Stadium in Sheffield, England. One victim died this June of aspiration pneumonia, to which he had been left vulnerable because of injuries from the disaster.
July 2, 1990 — During the annual hajj in Saudi Arabia, 1,426 Muslim pilgrims, mainly from Asia, die in and around a long pedestrian tunnel leading from Mecca to Mina.
January 13, 1991 — Forty-two people are killed when fans try to escape brawls at Oppenheimer Stadium in South Africa.
May 23, 1994 — A crush of pilgrims at the hajj leaves 270 Muslim pilgrims dead.
November 23, 1994 — A panicked crush during a political protest in Nagpur, India, leaves 113 dead.
October 16, 1996 — Eighty-four people die and 147 are injured as panicked fans are crushed and smothered before a World Cup qualifier between Guatemala and Costa Rica in Guatemala City.
April 9, 1998 — A crush of pilgrims on a bridge in Mecca leaves 118 hajj pilgrims dead.
April 11, 2001 — At least 43 people are crushed to death during a soccer match at Ellis Park in Johannesburg, South Africa.
May 9, 2001 — More than 120 people are killed when police fire tear gas into the rowdy crowd in a stadium in the Ghanaian capital Accra, leading to panic.
February 17, 2003 — Twenty-one are crushed to death in the stairway exit to E2, a nightclub in Chicago.
February 20, 2003 — Stage pyrotechnics during a Great White concert at the Station nightclub in Warwick, Rhode Island, spark a fire that kills 100 people and injures more than 200 others.
February 1, 2004 — A panic during a hajj ritual at the Jamarat Bridge near Mecca leaves 251 people dead.
January 25, 2005 — A panic among Hindu pilgrims near Mandhradevi temple in Maharashtra, India, leaves 265 people dead.
August 31, 2005 — At least 640 Shiite Muslim pilgrims in Baghdad are killed when a railing on a bridge collapses during a religious procession, sending scores into the Tigris River.
January 12, 2006 — A panic among Muslim pilgrims during a hajj ceremony near Mecca leaves 345 people dead.
February 4, 2006 — Seventy-eight people are killed in a panicked crush that happened at PhilSports Arena stampede in Manila, Philippines, as they were waiting for a TV variety show audition.
September 30, 2008 — At least 168 people are killed and 100 are injured when thousands of Hindu pilgrims are caught in a panic at a temple in Jodhpur, India.
July 24, 2010 — Twenty-one people die and more than 650 are injured in a crush in a packed tunnel that was the sole access point to the Love Parade music festival in Duisburg, Germany.
November 22, 2010 — More than 340 people are killed and hundreds of others are injured during a panicked crush at a festival in the Cambodian capital, Phnom Penh.
January 27, 2013 — A fire kills more than 200 people at the Kiss nightclub in Santa Maria, Brazil.
September 24, 2015 — At least 2,411 Muslim pilgrims die in a crush during the hajj in Saudi Arabia.
April 30, 2021 — Forty-five people are killed and dozens more are wounded in a panicked crush at the annual Mount Meron pilgrimage in Israel.
November 5, 2021 — Fans at a Houston music festival surge toward the stage during a performance by rapper Travis Scott, triggering panic that leaves at least eight people dead and many more injured.
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