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Major Incidents

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Major Incidents

What is a major Incident?

In Health Service terms

A major incident can be defined as any incident where the location, number, severity or type of live casualties requires extraordinary resources.

Classification of a major incident

It is convenient to classify major incidents in three ways.

  1. Natural or manmade
  2. Simple or compound
  3. Compensated or uncompensated.

Natural or Manmade
A natural major incident is the result of earthquake, flood, fire, volcano, tsunami, drought, famine or pestilence. To some extent the natural disaster will be self-propagating: following a flood or earthquake those left homeless and starving will be vulnerable to the disases associated with squalor.

The diversity of manmade incidents is very broad, but certain patterns are clear. The ingredients are present for a major incident when large numbers of people gather together to travel, to work, or for leisure. In some circumstances the incident will be the result of a deliberate terrorist activity.

Phases of a Major Incident

There are three phases to a major incident.

  1. Preparation
  2. Response
  3. Recovery

Manmade major incidents (for example, transport incidents and stadia incidents) may be prevented by enforcement of legislation. Natural incidents may be anticipated, although rarely prevented, but adequate planning can ameliorate their effects. There are three elements to medical preparation for a major incident.

  • Planning
  • Equipment
  • Training

Major incident Medical Management and Support (MIMMS) provides a structured "all-hazards" approach to the major incident scene (major incident medical management) and to dealing with multiple casualties (major incident medical support), irrespective of the nature of the incident.

This phase may last days or weeks within the secondary healthcare system, but may last years in the community punctuated by an inquest, protracted legal proceedings, and anniversaries.


The "all hazard" structured response to a major incident can be adopted by the Health Services commanders at the scene and by all other members of the Health Services involved in the response. The approach is encapsulated in seven key principles.

The generic nature of these principles has been shown to cross interservice boundaries at the scene, historical civilian-military boundaries, and international boundaries.

Management and support priorities:

Each emergency service at the scene has a commander. "Command" is therefore vertical within each service. Overall responsibility will be taken by one service at the scene and this service is said to have control. "Control" is therefore horizontal across the services.

The code of safety is remembered as Self, Scene, Survivors.

Communication is the commonest failing at the scene of a major incident. Effective communication between the incident commanders must be established early and arrangements made for regular liaison.

A rapid assessment of the scene to estimate the number and severity of injured is essential. The information gathered is used to determine the initial Health Service response to the scene.

This is the sorting of casualties into priorites for treatment. The process is dynamic (priorities may later after treatment or while waiting for treatment) and must be repeated at every stage of the evacuation chain to detect these changes.

The aim of treatment at a major incident is to "do the most for the most", that is, to identify and treat the savageable. The actual treatment delivered will reflect the skills of the providers, the severity of the injuries, and the time the patient spends on the scene.

In a convential major incident in a developed country most casualties will be moved to hospital by emergency ambulance. Other forms of transport can be used and it is the responsiblity of the Health Service commanders to ensure that patients are transported in an appropriate vehicle, with the necessary in-transit care.