Stampede or Crushing (Human)

Primary reference(s)

Illiyas, F., S. Mani, A. Pradeepkumar and K. Mohan, 2013. Human stampedes during religious festivals: a comparative review of mass gathering emergencies in India. International Journal of Disaster Risk Reduction, 5:10-18.

Additional scientific description

With population growth and a constant increase in human travels, mass gatherings are becoming more frequent and attract increasing numbers of participants (Johansson et al., 2012). Mass gatherings can be defined as a concentration of people at a specific location for a specific purpose over a set period of time, and which has the potential to strain the planning and response resources of the country or the community (WHO, 2015).

Mass gatherings are either spontaneous, such as at train stations during rush hour (Johansson et al., 2012) or are planned, such as at sport, cultural, religious, or political events (WHO, 2015). The Hajj pilgrimage in Saudi Arabia and the Kumbh Mela in India are the biggest regular mass gatherings globally, bringing millions of pilgrims together (Ahmed et al., 2006; Illiyas et al., 2013). Mass gatherings may affect health in different ways and crowd disasters may occur, including the collapse of infrastructure, fire incidents, terrorist attacks, violence riots, and human stampedes (Soomaroo and Murray, 2012; WHO, 2015; Still, 2019).

Stampedes are often described as the “disruption of the orderly movement of crowds…leading to injuries and fatalities” (Illiyas et al., 2013), often “in response to a perceived danger, loss of physical space”, or “a will to attain something seen as gratifying” (Ngai et al., 2009; Burkle et al., 2011; Illiyas et al., 2013). They carry high mortality rates and are, besides heat-related illnesses, the most common cause of mortality in mass gatherings (Steffen et al., 2012; Still, 2019).

Most human stampede casualties result from traumatic asphyxia caused by external compression of the thorax and/or upper abdomen, resulting in complete or partial cessation of respiration. It has been reported that significant compression forces can be present with even moderate crowds; forces of up to 4500 N (1000 lb) can be generated by just six to seven people pushing in a single direction with forces large enough to bend steel railings (Ngai et al., 2009).

Although survivors of human stampedes and autopsy reports suggest traumatic asphyxia as the primary cause of death, other mechanisms have been considered, including myocardial infarction, direct crushing injury to intrathoracic or intraabdominal organs, head injury, and neck compression. All these mechanisms are possible; however, little actual supportive evidence exists. It has been concluded from autopsy findings that “people who succumb in these scenarios typically die (standing up) in a vertical position” due to compression force and “do not collapse to the floor until after the crowd density and pressure have been relieved. Compressive forces applied front to back or vice versa resulted in ventilatory failure, whereas those experiencing compressive forces from side to side were spared, presumably because chest expansion was not compromised to the same extent” (Ngai et al., 2009).

The full spectrum of injuries – including fractures, dislocations, and other mechanical injuries – may be expected. Among survivors, many may suffer from posttraumatic stress, grief, or survivor guilt and require psychological counselling or intervention (Ngai et al., 2009).

Metrics and numeric limits

Not available.

Examples of drivers, outcomes and risk management

Much of what is known about human stampedes is derived from anecdotal news reports and observations. In recent decades, the toll from human stampedes has been increasingly well documented. Although there appears to be an uptick in the occurrence of deadly stampedes mirroring risks of increasing overall population densities, especially in low and middle-income countries, the number of reports may in reality reflect greater sharing of information via mass media. Numerous other events before the 1990s, particularly in less developed countries, may have resulted in sizeable stampedes that were unreported. In general, injuries are estimated or are not recorded, whereas direct deaths (not including deaths following injuries) are more precisely reported and readily obtained (Ngai et al., 2009; Still, 2019). Often stampede and crushing events occur due to the systematic failure of organisations to provide a safe environment for places of public assembly (Still, 2019).

Between 1980 and 2007, the Ngai method identified 215 stampede events worldwide, and 350 events between 1980 and 2012. Between 1980 and 2007, 7069 deaths and 14,078 injuries were caused by stampedes (Hsieh et al., 2009) increasing to 10,243 deaths and 22,445 injuries between 1980 and 2012 (Ngai et al., 2009). Most stampedes occur indoors, during daytime hours, and in sports events (Hsieh et al., 2009). Uni-directional mechanism increased the fatality rate 3.46-fold, believed to be due to the confluence of forces in the same direction (Hsieh et al., 2009). Women, children, and older people were reportedly more affected because they were less able to defend themselves from external weight pressure (De Almeida and Von Schreeb, 2019).

Risk management: Stampede or crushing (human) hazards are associated with mass gatherings. A mass gathering is an organised or unplanned event where the number of people attending is sufficient to strain the planning and response resources of the community, state or nation hosting the event. Sporting events, music festivals, political demonstrations and religious pilgrimages can be mass gathering events. A safe and healthy mass gathering requires early multi-sectoral preparation involving event organisers, health emergency managers, public health authority representatives, local hospital emergency departments, first-aid personnel and other sectoral partners, including police and emergency services (WHO and PHE, 2017).

A risk assessment for any event where a stampede or crushing hazard is a risk, informs the selection and implementation of risk reduction measures, response planning, and capacity development for health functions, including: mass casualty management; on-site trauma care and local hospitals; disease surveillance and outbreak response; environmental health and food safety; public information and health promotion; leadership, coordination and communication; and emergency preparedness and response to natural hazards, transport crashes, stampedes, and security incidents (WHO and PHE, 2017).