Stampede or Crushing (Human)

Unique identifier / Notation

SO0302

Synonyms

Crush Mass panic Crowd disaster Trampling Crowd quakes Mass-crowded stampede Trampling accident

Stampede or crushing is the surge of individuals in a crowd, in response to real or perceived danger or loss of physical space. It often disrupts the orderly movement of crowds resulting in movement for self-protection leading to increased localised crowd density and physical compression of the human bodies (Adapted from Burkle & Hsu, 2011; Illiyas et al., 2013; Ngai, et al., 2009).

Primary reference(s)

Burkle, F.M. Jr. and E.B. Hsu, 2011. Ram Janki Temple: understanding human stampedes. Lancet, 377:106-107.

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.

Ngai, K.M., F.M. Burkle Jr., A. Hsu and E.B. Hsu, 2009. Human stampedes: a systematic review of historical and peer-reviewed sources. Disaster Medicine and Public Health Preparedness, 3:191-195.

Annotations

Additional scientific description

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). With population growth and a constant increase in human mobility, mass gatherings are becoming more frequent and attract increasing numbers of participants (Johansson et al., 2012).

Mass gatherings are either spontaneous, such as at train stations during rush hour (Johansson et al., 2012) or are planned, such as sporting events, cultural events, music festivals, religious pilgrimages, 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, violent riots, and human stampedes (Soomaroo & Murray, 2012; WHO, 2015; Still, 2019) causing loss of lives. Stampedes resulting in crushing, 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 crush casualties result in traumatic asphyxia caused by external compression of the thorax and/or upper abdomen, resulting in partial or complete 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.... 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

There is no standardised metric to measure the impact of stampedes. However, there is much debate as to how to categorise stampedes, some academics think they should be categorised by the number of reported deaths as a result of the incident, whilst others think the number of injuries or fatality rates should be considered.

Key relevant UN convention / multilateral treaty

International Health Regulations (2005) (WHO, 2016).

Drivers

Much of what is reliably known about mass-gathering disasters is derived from post-event inquiries. Anecdotal news reports and observations also provide information on events. Frequently reported factors that trigger a stampede include rumours of a threat, sudden loud sounds, narrow passage and overcrowding.

Most stampedes occur indoors, during daytime hours, and in sports events (Hsieh et al., 2009)

Impacts

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 (de Almeida and von Schreeb, 2019), 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, resulting in 7069 deaths and 14,078 injuries (Hsieh et al., 2009) increasing to 10,243 deaths and 22,445 injuries between 1980 and 2012 (Ngai 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 & Von Schreeb, 2019).

Multi-hazard context

Rapid-onset hazards (Meteorological and Hydrological, Extraterrestrial, Geohazard, Environmental, Chemical, Technological, or Societal) occurring during a mass gathering may lead to a stampede. Stampedes may trigger other hazards (Environmental, Chemical, Technological, or Societal).

Risk Management

Both organised and unplanned mass-gatherings strain the planning and response resources of the community, state or nation hosting the event. 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 & PHE, 2017). Findings from the Seoul Halloween crushing emphasise the importance of proactive measures including proper police presence and response, managing the flow of people, and effective communication.

A risk assessment is an essential part of planning for any event. This informs the selection and implementation of risk reduction measures, response planning, and capacity development for health operations, 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 (WHO and PHE, 2017).