Mass decontamination

Mass decontamination (abbreviated mass decon) is the decontamination of large numbers of people, in the event of industrial, accidental, or intentional contamination by toxic, infective, caustic, polluted, or otherwise unhealthful or damaging substances.

Mass decontamination, referred to as mass decon from here forth is the process of cleaning one’s body, clothes, and equipment to remove harmful nuclear, biological, or chemical (NBC) agents such as anthrax, a biological agent, chemicals such as chlorine, harmful gases such as mustard gas and even some nerve agents. The decon process can also be used to rid people, places and things from viruses, toxins, and radioactive material. Furthermore, it is important to note that these events can happen anywhere at any time. The common misconception that mass casualty exposures only happen in urban or industrial areas is simply not true. History has shown that these events can happen in both heavily populated and rural areas. This is why it is crucial for every city, county and state to be prepared for these events.

Scenes of mass contamination are often scenes of collective hysteria, with hundreds or thousands of victims in a state of panic. Therefore, mass decontamination may require police, security, or rescue supervision to help control panic and keep order. Under these circumstances, mass decon can take on some features of mass arrests, with victims forcibly rounded up, then treated inside impromptu detention areas. Successful municipal decontaminations are greatly aided by a close collaboration between police and fire departments. An organised, informed and aware populace can be better prepared for possible emergencies, and is less likely to panic. In some situations volunteers may be needed to augment or replace rescue/security personnel to help maintain calm and/or assist with decontamination procedures.

For example, the Australian "Workplace Relations Act 1996" calls for detention of victims of a hazardous materials (hazmat) incident:

The Federal Emergency Management Agency (FEMA) also suggests that:

Even some of the clear-thinking subjects may resist efforts to decontaminate them. Those who know or think they have not been contaminated may resist being herded into close quarters with sick or toxin-ridden victims who still have the potential to harm those nearby. Those carrying weapons or some form of contraband may require force to part them from their contaminated clothes and effects. Others may simply fear contact with the authorities, as well as separation from family and loss of job resulting from quarantines, more than they fear the contaminant.

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Wikipedia