Crowd collapses and crushes

Crowd Collapses and Crushes: Understanding the Catastrophic Incidents

Imagine a crowded stadium where everyone is packed so tightly that you can barely move, let alone breathe. This isn’t just uncomfortable—it’s dangerous. Crowd collapses and crushes are catastrophic incidents that occur when a body of people becomes dangerously overcrowded. The environment may feel cramped but manageable at around 5 people per square meter, but as numbers increase to 8-10 people per square meter, individuals become pressed against each other and can be swept along by the motion of the crowd.

Progressive Collapse: A Metaphor for Disaster

Under these conditions, the crowd may undergo a progressive collapse where the pressure pushes people off their feet, resulting in people being trampled or crushed by the weight of others. At even higher densities, the pressure on each individual can cause them to be crushed or asphyxiated while still upright. It’s like a house of cards; when one card falls, it triggers a chain reaction that brings down everything else.

Crushes and Their Tragic Consequences

The critical factor is crowd density rather than crowd size. Crowd collapses and crushes are often reported incorrectly as human stampedes, which typically occur when a large group of people try to get away from a perceived risk. But the reality is far more complex. There were 232 deaths and over 66,000 injuries in the ten years between 1992 and 2002 due to such incidents, but crowd scientists believe that such casualties are both vastly under-reported and increasing in frequency.

Understanding Crowd Dynamics

A crowd collapse occurs when a crowd is so dense that each individual is touching others all around and is supported by those around. If a person then falls, the support to those around is lost, causing people to fall into the void. This process repeats, causing a bigger void until the pressure eases. At even higher densities (approaching 10 people per square meter), a crowd can become so packed that people are crushed together to such an extent they can no longer breathe and are asphyxiated.

Not Stampedes: Panic Is Not the Cause

The term ‘stampede’ is usually used in reference to animals fleeing a threat, but crowd scientists believe that mass fatalities are unlikely to be caused by stampedes. They panic because they are dying. Paul Torrens states the “idea of the hysterical mass is a myth.” Incidents involving crowds are often reported as results of panic, but this is a myth that distracts from real causes such as crowd crushes.

Causes and Prevention

The causes of death in crowd collapse and crush incidents include asphyxiation caused by vertical or horizontal stacking, bone fractures and trampling injuries. Prevention methods include organization and traffic control with crowd barriers, feedback from people being crushed to the crowd behind, provided by police or observers, and simple measures such as spreading movements over time.

Lessons from Tragedies

Inexperienced security officers can contribute to crushes if they misunderstand behavior in a dense crowd. There is risk of a crush when crowd density exceeds 5 people per square meter. Warning signs include being touched on all four sides and feeling shock waves traveling through the crowd.

Conclusion: The Importance of Crowd Management

Crowd collapses and crushes are not just tragic accidents; they are preventable disasters. By understanding the dynamics of crowd behavior, implementing effective management strategies, and recognizing the warning signs, we can significantly reduce the risk of such incidents. Remember, in a crowded space, every individual’s safety depends on everyone else’s awareness and preparedness.