Emergency

An incident, to be an emergency, conforms to one or more of the following, if it:

• Poses an immediate threat to life, health, property, or environment
• Has already caused loss of life, health detriments, property damage, or environmental damage
• has a high probability of escalating to cause immediate danger to life, health, property, or environment

In the United States, most states mandate that a notice be printed in each telephone book that requires that someone must relinquish use of a phone line, if a person requests the use of a telephone line (such as a party line) to report an emergency. State statutes typically define an emergency as, "...a condition where life, health, or property is in jeopardy, and the prompt summoning of aid is essential."[2]

Whilst most emergency services agree on protecting human health, life and property, the environmental impacts are not considered sufficiently important by some agencies. This also extends to areas such as animal welfare, where some emergency organizations cover this element through the "property" definition, where animals owned by a person are threatened (although this does not cover wild animals). This means that some agencies do not mount an "emergency" response where it endangers wild animals or environment, though others respond to such incidents (such as oil spills at sea that threaten marine life). The attitude of the agencies involved is likely to reflect the predominant opinion of the government of the area.

Agencies across the world have different systems for classifying incidents, but all of them serve to help them allocate finite resource, by prioritising between different emergencies.

The first stage of any classification is likely to define whether the incident qualifies as an emergency, and consequently if it warrants an emergency response. Some agencies may still respond to non-emergency calls, depending on their remit and availability of resource. An example of this would be a fire department responding to help retrieve a cat from a tree, where no life, health or property is immediately at risk.

Following this, many agencies assign a sub-classification to the emergency, prioritising incidents that have the most potential for risk to life, health or property (in that order). For instance, many ambulance services use a system called the Advanced Medical Priority Dispatch System (AMPDS) or a similar solution.[4][5] The AMPDS categorises all calls to the ambulance service using it as either 'A' category (immediately life-threatening), 'B' Category (immediately health threatening) or 'C' category (non-emergency call that still requires a response). Some services have a fourth category, where they believe that no response is required after clinical questions are asked.

Another system for prioritizing medical calls is known as Emergency Medical Dispatch (EMD).[6][7] Jurisdictions that use EMD typically assign a code of "alpha" (low priority), "bravo" (medium priority), "charlie" (requiring advanced life support), delta (high priority, requiring advanced life support) or "echo" (maximum possible priority, e.g., witnessed cardiac arrests) to each inbound request for service; these codes are then used to determine the appropriate level of response.[8][9][10]

Other systems (especially as regards major incidents) use objective measures to direct resource. Two such systems are SAD CHALET and ETHANE,[11] which are both mnemonics to help emergency services staff classify incidents, and direct resource.[12] Each of these acronyms helps ascertain the number of casualties (usually including the number of dead and number of non-injured people involved), how the incident has occurred, and what emergency services are required.

Most developed countries have a number of emergency services operating within them, whose purpose is to provide assistance in dealing with any emergency. They are often government operated, paid for from tax revenue as a public service, but in some cases, they may be private companies, responding to emergencies in return for payment, or they may be voluntary organisations, providing the assistance from funds raised from donations.

Most developed countries operate three core emergency services:

• Police – handle mainly crime-related emergencies.
• Fire – handle fire-related emergencies and usually possess secondary rescue duties.
• Medical – handle medical-related emergencies.

There may also be a number of specialized emergency services, which may be a part of one of the core agencies, or may be separate entities who assist the main agencies. This can include services, such as bomb disposal, search and rescue, and hazardous material operations.

The Military and the Amateur Radio Emergency Service (ARES) or Radio Amateur Civil Emergency Service (RACES) help in large emergencies such as a disaster or major civil unrest.

Emergency action principles are key 'rules' that guide the actions of rescuers and potential rescuers. Because of the inherent nature of emergencies, no two are likely to be the same, so emergency action principles help to guide rescuers at incidents, by sticking to some basic tenets.

The adherence to (and contents of) the principles by would-be rescuers varies widely based on the training the people involved in emergency have received, the support available from emergency services (and the time it takes to arrive) and the emergency itself.

A graphic representation of the four phases in emergency management.

There are many emergency services protocols that apply in an emergency, which usually start with planning before an emergency occurs. One commonly used system for demonstrating the phases is shown here on the right.

The planning phase starts at preparedness, where the agencies decide how to respond to a given incident or set of circumstances. This should ideally include lines of command and control, and division of activities between agencies. This avoids potentially negative situations such as three separate agencies all starting an official emergency shelter for victims of a disaster.

Following an emergency occurring, the agencies then move to a response phase, where they execute their plans, and may end up improvising some areas of their response (due to gaps in the planning phase, which are inevitable due to the individual nature of most incidents).

Agencies may then be involved in recovery following the incident, where they assist in the clear up from the incident, or help the people involved overcome their mental trauma.

The final phase in the circle is mitigation, which involves taking steps to ensure no re-occurrence is possible, or putting additional plans in place to ensure less damage is done. This should feed back into the preparedness stage, with updated plans in place to deal with future emergencies, thus completing the circle.

In the event of a major incident, such as civil unrest or a major disaster, many governments maintain the right to declare a state of emergency,[24] which gives them extensive powers over the daily lives of their citizens, and may include temporary curtailment on certain civil rights, including the right to trial. For instance to discourage looting of an evacuated area, a shoot on sight policy, however unlikely to occur, may be publicized.

Media related to Emergencies at Wikimedia Commons