
Emergency evacuation is the urgent immediate egress or escape of people away from an area that contains an imminent threat, an ongoing threat or a
hazard
A hazard is a potential source of harm
Harm is a moral and legal concept.
Bernard Gert construes harm as any of the following:
* pain
* death
* disability
* mortality
* loss of abil ity or freedom
* loss of pleasure.
Joel Feinberg giv ...
to lives or property.
Examples range from the small-scale evacuation of a building due to a
storm
A storm is any disturbed state of the natural environment or the atmosphere
An atmosphere () is a layer of gas or layers of gases that envelop a planet, and is held in place by the gravity of the planetary body. A planet retains an atmos ...
or fire to the large-scale evacuation of a city because of a flood, bombardment or approaching
weather system
In meteorology, a low-pressure area, low area or low is a region where the atmospheric pressure is lower than that of surrounding locations. Low-pressure areas are commonly associated with inclement weather (such as cloudy, windy, with possible ...
, especially a
tropical cyclone
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depend ...
. In situations involving hazardous materials or possible
contamination
Contamination is the presence of a constituent, impurity, or some other undesirable element that spoils, corrupts, infects, makes unfit, or makes inferior a material, physical body, natural environment, workplace, etc.
Types of contamination
W ...
, evacuees may be
decontaminated prior to being transported out of the contaminated area. Evacuation planning is an important aspect of business management of which emergency evacuation forms a part.
Reasons for evacuation

Evacuations may be carried out before, during, or after disasters such as:
*
Natural disaster
A natural disaster is "the negative impact following an actual occurrence of natural hazard in the event that it significantly harms a community". A natural disaster can cause loss of life or damage property, and typically leaves some econ ...
s
**
Eruptions
Several types of volcanic eruptions—during which lava, tephra (ash, lapilli, volcanic bombs and volcanic blocks), and assorted gases are expelled from a volcanic vent or fissure—have been distinguished by volcanologists. These are often ...
of
volcano
A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface.
On Earth, volcanoes are most often found where tectonic plates are ...
es
**
Tropical cyclone
A tropical cyclone is a rapidly rotating storm system characterized by a low-pressure center, a closed low-level atmospheric circulation, strong winds, and a spiral arrangement of thunderstorms that produce heavy rain and squalls. Depend ...
s
**
Flood
A flood is an overflow of water ( or rarely other fluids) that submerges land that is usually dry. In the sense of "flowing water", the word may also be applied to the inflow of the tide. Floods are an area of study of the discipline hydrol ...
s
**
Earthquake
An earthquake (also known as a quake, tremor or temblor) is the shaking of the surface of the Earth resulting from a sudden release of energy in the Earth's lithosphere that creates seismic waves. Earthquakes can range in intensity, from ...
s
**
Tsunami
A tsunami ( ; from ja, 津波, lit=harbour wave, ) is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake. Earthquakes, volcanic eruptions and other underwater explo ...
s
**
Wildfires/Bushfires
*
Industrial accidents
A work accident, workplace accident, occupational accident, or accident at work is a "discrete occurrence in the course of work" leading to physical or mental occupational injury. According to the International Labour Organization (ILO), more tha ...
**
Chemical spill A chemical accident is the unintentional release of one or more chemical hazard substances which could harm human health and the environment. Such events include fires, explosions, leakages or release of toxic or hazardous materials that can cause ...
**
Nuclear accident
A nuclear and radiation accident is defined by the International Atomic Energy Agency (IAEA) as "an event that has led to significant consequences to people, the environment or the facility. Examples include lethal effects to individuals, lar ...
* Transport
**
Road accidents
**
Train wreck
A train wreck, train collision, train accident or train crash is a type of disaster involving one or more trains. Train wrecks often occur as a result of miscommunication, as when a moving train meets another train on the same track; or an acci ...
**
Emergency aircraft evacuation
Emergency aircraft evacuation refers to emergency evacuation from an aircraft which may take place on the ground, in water, or mid-flight. There are standard evacuation procedures and special evacuation equipment.
Commercial airplanes
Commercial ...
*
Fire
Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products.
At a certain point in the combustion reaction, called the ignition ...
s
**
Industrial fire
An industrial fire is a type of industrial disaster involving a conflagration which occurs in an industrial setting. Industrial fires often, but not always, occur together with explosions. They are most likely to occur in facilities where there i ...
s
*
Military attacks
**
Bombings
A bomb is an explosive weapon that uses the exothermic reaction of an explosive material to provide an extremely sudden and violent release of energy. Detonations inflict damage principally through ground- and atmosphere-transmitted mechanica ...
**
Terrorist attacks
The following is a list of terrorist incidents that have not been carried out by a state or its forces (see state terrorism and state-sponsored terrorism). Assassinations are listed at List of assassinated people.
Definitions of terrori ...
**
Military battles
** Imminent
nuclear war
Nuclear warfare, also known as atomic warfare, is a theoretical military conflict or prepared political strategy that deploys nuclear weaponry. Nuclear weapons are weapons of mass destruction; in contrast to conventional warfare, nuclear w ...
*
Structural failure
Structural integrity and failure is an aspect of engineering that deals with the ability of a structure to support a designed structural load (weight, force, etc.) without breaking and includes the study of past structural failures in order to ...
*
Viral outbreak
A pandemic () is an epidemic of an infectious disease that has spread across a large region, for instance multiple continents or worldwide, affecting a substantial number of individuals. A widespread endemic disease with a stable number of in ...
*
Robbery
Robbery is the crime of taking or attempting to take anything of value by force, threat of force, or by use of fear. According to common law, robbery is defined as taking the property of another, with the intent to permanently deprive the perso ...
Planning
Emergency evacuation plans are developed to ensure the safest and most efficient evacuation time of all expected residents of a structure, city, or region. A benchmark "evacuation time" for different hazards and conditions is established. These benchmarks can be established through using best practices, regulations, or using
simulations
A simulation is the imitation of the operation of a real-world process or system over time. Simulations require the use of models; the model represents the key characteristics or behaviors of the selected system or process, whereas the s ...
, such as modeling the flow of people in a building, to determine the benchmark. Proper planning will use multiple exits,
contra-flow lane
In transport engineering nomenclature, a counterflow lane or contraflow lane is a lane in which traffic flows in the opposite direction of the surrounding lanes.
Contraflow lanes are often used for bicycles or bus rapid transit on what are o ...
s, and special technologies to ensure full, fast and complete evacuation. Consideration for personal situations which may affect an individual's ability to evacuate is taken into account, including alarm signals that use both aural and visual alerts, and also evacuation equipment such as sleds, pads, and chairs for non-ambulatory people. Considering the persons with a
disability
Disability is the experience of any condition that makes it more difficult for a person to do certain activities or have equitable access within a given society. Disabilities may be Cognitive disability, cognitive, Developmental disability, dev ...
during an emergency evacuation is important. This is because it is crucial that every user gets out of the building or to a safe place in the building, thus also the persons with disabilities or the non- ambulatory people. Regulations such as building codes can be used to minimize the negative consequences of the threat triggering the evacuation and optimize the need to self-evacuate without causing alarm. Proper planning, that covers designated actions to ensure safety of the users in emergencies, will implement an all-hazards approach so that plans can be reused for multiple hazards that could exist.
Therefore, key elements for emergency planning and preparedness are early warnings for the people inside the building by emergency helpers but also voice assistance, facilities to leave the building safe and fast, such as exit routes and good evacuation practices. The evacuation managing team must know what to do in emergency situations and which actions to take.
Evacuation sequence
The sequence of an evacuation can be divided into the following phases:
# detection
# decision
# alarm
# reaction
# movement to an area of refuge or an assembly station
# transportation
The time for the first four phases is usually called
pre-movement time.
The particular phases are different for different objects, e.g., for ships a distinction between assembly and embarkation (to boats or rafts) is made. These are separate from each other. The decision whether to enter the boats or rafts is thus usually made after assembly is completed.
Small scale evacuations

The strategy of individuals in evacuating buildings was investigated by John Abrahams in 1994. The
independent variable
Dependent and independent variables are variables in mathematical modeling, statistical modeling and experimental sciences. Dependent variables receive this name because, in an experiment, their values are studied under the supposition or demand ...
s were the complexity of the building and the movement ability of the individuals. With increasing complexity and decreasing motion ability, the strategy changes from "fast egress", through "slow egress" and "move to safe place inside building" (such as a staircase), to "stay in place and wait for help". The third strategy is the notion of using a designated "safe haven" on the floor. This is a section of the building that is reinforced to protect against specific hazards, such as fire, smoke or structural collapse. Some hazards may have safe havens on each floor, while a hazard such as a tornado, may have a single safe haven or
safe room
A safe room or panic room is a fortified room that is installed in a private residence or business to provide a safe shelter, or hiding place, for the inhabitants in the event of a break in, home invasion, tornado, terror attack, or other thr ...
. Typically persons with limited mobility are requested to report to a safe haven for rescue by first responders. In most buildings, the safe haven will be in the stairwell.
By investing the strategy of individuals in evacuating buildings, the variable human reactions is a complex factor to take into account during an evacuation. This is a critical factor for escaping fast out of the building or to a "safe haven". During an emergency evacuation, people do not immediately react after hearing the alarm signal. This is because an evacuation drill is more common. Therefore, they will start evacuating when there is more information given about the degree of danger. During an evacuation, people often use the most known escape route, this is often the route through which they entered the building. Thereby, people mostly adapt the role follower in emergencies. These human reactions will determinate the strategy of individuals in evacuating buildings.

The most common equipment in buildings to facilitate emergency evacuations are
fire alarm
A fire alarm system warns people when smoke, fire, carbon monoxide or other fire-related or general notification emergency, emergencies are detected. These alarms may be activated automatically from smoke detectors and heat detectors or may also ...
s,
exit sign
An exit sign is a pictogram or short text in a public facility (such as a building, aircraft, or boat) denoting the location of the closest emergency exit to be used in case of fire or other emergency that requires rapid evacuation. Most rele ...
s, and
emergency light
An emergency light is a battery-backed lighting device that switches on automatically when a building experiences a power outage.
In the United States, emergency lights are standard in new commercial and high occupancy residential buildings, ...
s. Some structures need special
emergency exit
An emergency exit in a structure is a special exit for emergencies such as a fire: the combined use of regular and special exits allows for faster evacuation, while it also provides an alternative if the route to the regular exit is blocked.
...
s or
fire escape
A fire escape is a special kind of emergency exit, usually mounted to the outside of a building or occasionally inside but separate from the main areas of the building. It provides a method of escape in the event of a fire or other emergency th ...
s to ensure the availability of alternative escape paths. Commercial passenger vehicles such as buses, boats, and aircraft also often have evacuation lighting and signage, and in some cases
window
A window is an opening in a wall, door, roof, or vehicle that allows the exchange of light and may also allow the passage of sound and sometimes air. Modern windows are usually glazed or covered in some other transparent or translucent materia ...
s or extra doors that function as emergency exits. Commercial
emergency aircraft evacuation
Emergency aircraft evacuation refers to emergency evacuation from an aircraft which may take place on the ground, in water, or mid-flight. There are standard evacuation procedures and special evacuation equipment.
Commercial airplanes
Commercial ...
is also facilitated by
evacuation slide
An evacuation slide is an inflatable slide used to evacuate an aircraft quickly. An escape slide is required on all commercial (passenger carrying) aircraft where the door sill height is such that, in the event of an evacuation, passengers wou ...
s and pre-flight safety briefings. Military aircraft are often equipped with
ejection seat
In aircraft, an ejection seat or ejector seat is a system designed to rescue the aircraft pilot, pilot or other aircrew, crew of an aircraft (usually military) in an emergency. In most designs, the seat is propelled out of the aircraft by an ex ...
s or
parachute
A parachute is a device used to slow the motion of an object through an atmosphere by creating drag or, in a ram-air parachute, aerodynamic lift. A major application is to support people, for recreation or as a safety device for aviators, who ...
s. Water vessels and commercial aircraft that fly over water are equipped with
personal flotation device
A personal flotation device (PFD; also referred to as a life jacket, life preserver, life belt, Mae West, life vest, life saver, cork jacket, buoyancy aid or flotation suit) is a flotation device in the form of a vest or suite that is worn by a ...
s and
life raft
A lifeboat or liferaft is a small, rigid or inflatable boat carried for emergency evacuation in the event of a disaster aboard a ship. Lifeboat drills are required by law on larger commercial ships. Rafts (raft, liferafts) are also used. In t ...
s.
Since the emergence of
The Internet of Things technologies, new techniques are appearing, which involves new equipment. Most of them are wireless devices such as IDs scanner,
beacons
A beacon is an intentionally conspicuous device designed to attract attention to a specific location. A common example is the lighthouse, which draws attention to a fixed point that can be used to navigate around obstacles or into port. More mod ...
or backscatter system. The new techniques are for example based on a
communication protocol
A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any kind of variation of a physical quantity. The protocol defines the rules, syntax, semantics (computer scien ...
such as
Wi-Fi
Wi-Fi () is a family of wireless network protocols, based on the IEEE 802.11 family of standards, which are commonly used for local area networking of devices and Internet access, allowing nearby digital devices to exchange data by radio wave ...
,
Bluetooth
Bluetooth is a short-range wireless technology standard that is used for exchanging data between fixed and mobile devices over short distances and building personal area networks (PANs). In the most widely used mode, transmission power is limi ...
,
UWB or
RFID
Radio-frequency identification (RFID) uses electromagnetic fields to automatically identify and track tags attached to objects. An RFID system consists of a tiny radio transponder, a radio receiver and transmitter. When triggered by an electromag ...
and the use of
indoor positioning system
An indoor positioning system (IPS) is a network of devices used to locate people or objects where GPS and other satellite technologies lack precision or fail entirely, such as inside multistory buildings, airports, alleys, parking garages, and und ...
.
The use of The Internet of Things technologies in small scale evacuations can result in a faster evacuation time: Mostly by localizing the fire sources, analysing the fire spreading inside the building or finding people that are trapped inside the building.
Some buildings can have a monitoring interface that provides all these kind of information to evacuate in the best way possible.
Large scale evacuations
The evacuation of districts is part of
disaster management
Emergency management or disaster management is the managerial function charged with creating the framework within which communities reduce vulnerability to hazards and cope with disasters. Emergency management, despite its name, does not actuall ...
. Many of the
largest evacuations have been in the face of wartime military attacks. Modern large scale evacuations are usually the result of natural disasters. The largest peacetime evacuations in the United States to date occurred during
Hurricane Gustav
Hurricane Gustav () was the second most destructive hurricane of the 2008 Atlantic hurricane season. The seventh tropical cyclone, third hurricane, and second major hurricane of the season, Gustav caused serious damage and casualties in Haiti, ...
and the
category-5 Hurricane Rita
Hurricane Rita was the most intense tropical cyclone on record in the Gulf of Mexico and the fourth-most intense Atlantic hurricane ever recorded. Part of the record-breaking 2005 Atlantic hurricane season, which included three of the top ten L ...
(2005) in a scare one month after the flood-deaths of
Hurricane Katrina
Hurricane Katrina was a destructive Category 5 Atlantic hurricane that caused over 1,800 fatalities and $125 billion in damage in late August 2005, especially in the city of New Orleans and the surrounding areas. It was at the time the cost ...
.
Hurricane evacuation

Despite mandatory evacuation orders, many people did not leave
,
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territorie ...
, as
Hurricane Katrina
Hurricane Katrina was a destructive Category 5 Atlantic hurricane that caused over 1,800 fatalities and $125 billion in damage in late August 2005, especially in the city of New Orleans and the surrounding areas. It was at the time the cost ...
approached. Even after the city was flooded and uninhabitable, some people still refused to leave their homes.
The longer a person has lived in a coastal area, the less likely they are to evacuate. A hurricane's path is difficult to predict. Forecasters know about hurricanes days in advance, but their forecasts of where the storm will hit are only educated guesses. Hurricanes give a lot of warning time compared to most disasters humans experience. However, this allows forecasters and officials to "cry wolf," making people take evacuation orders less seriously. Hurricanes can be predicted to hit a coastal town many times without the town ever actually experiencing the brunt of a storm. If evacuation orders are given too early, the hurricane can change course and leave the evacuated area unscathed. People may think they have weathered hurricanes before, when in reality the hurricane didn't hit them directly, giving them false confidence. Those who have lived on the coast for ten or more years are the most resistant to evacuating.
Public transportation
Since Hurricane Katrina, there has been an increase in evacuation planning. Current best practices include the need to use multi-modal transportation networks.
Hurricane Gustav
Hurricane Gustav () was the second most destructive hurricane of the 2008 Atlantic hurricane season. The seventh tropical cyclone, third hurricane, and second major hurricane of the season, Gustav caused serious damage and casualties in Haiti, ...
used military airlift resources to facilitate evacuating people out of the affected area. More complex evacuation planning is now being considered, such as using elementary schools as rally points for evacuation. In the United States, elementary schools are usually more numerous in a community than other public structures. Their locations and inherent design to accommodate bus transportation makes it an ideal evacuation point.
Registries
Most local communities maintain registries for special needs individuals. These opt-in registries help with planning, as those that need government evacuation assistance are identified before the disaster. Registries used after a disaster are being used to help reunite families that have become separated after a disaster.
Enforcing evacuation orders
In the United States, a person usually cannot be forced to evacuate. To facilitate voluntary compliance with mandatory evacuation orders first responders and disaster management officials have used creative techniques such as asking people for the names and contact of their next-of-kin, writing their Social Security Numbers on their limbs and torso to enable identification of remains, and refusing to provide government services in the affected area, including emergency services.
Personal Evacuation Kits
In preparation for emergency evacuation situations, experts often advise having an individual emergency evacuation kit prepared and on hand prior to the emergency. An emergency evacuation kit is a container of food, clothing, water, and other supplies that can be used to sustain an individual during lag time. Lag time is the period between the actual occurrence of an emergency and when organized help becomes available, generally 72 hours, though this can vary from a few hours to several days. It may take this long for authorities to get evacuation shelters fully up and functional. During this time, evacuees may suffer fairly primitive conditions; no clean water, heat, lights, toilet facilities, or shelter. An emergency evacuation kit, or 72-hour kit, can help evacuees to endure the evacuation experience with dignity and a degree of comfort.
Cyber-physical systems
The
development of digital infrastructure resources opened a new research area in the design of
cyber-physical system
A cyber-physical system (CPS) or intelligent system is a computer system in which a mechanism is controlled or monitored by computer-based algorithms. In cyber-physical systems, physical and software components are deeply intertwined, able to oper ...
s to provide the individual with safer options during an emergency evacuation.
See also
*
*
*
*
*
*
*
References
* Gershenfeld, Neil, Mathematical Modelling. OUP, Oxford, 1999.
* Hubert Klüpfel
A Cellular Automaton Model for Crowd Movement and Egress Simulation Dissertation, Universität Duisburg-Essen, 2003.
* Stollard, P. and L. Johnson, Eds., "Design against fire: an introduction to fire safety engineering design", London, New York, 1994.
* Künzer, L
Myths Of Evacuationin FeuerTRUTZ International 1.2016, p. 8-11
External links
Fire Safety Engineering Group at the University of Greenwich*
{{DEFAULTSORT:Emergency Evacuation
Safety
Emergency management
Disaster preparedness in the United States