An exit sign is a
pictogram
A pictogram (also pictogramme, pictograph, or simply picto) is a graphical symbol that conveys meaning through its visual resemblance to a physical object. Pictograms are used in systems of writing and visual communication. A pictography is a wri ...
or short text in a public facility (such as a building, aircraft, or boat) marking the location of the closest
emergency exit to be used in an emergency that necessitates rapid evacuation. Most
fire
Fire is the rapid oxidation of a fuel in the exothermic chemical process of combustion, releasing heat, light, and various reaction Product (chemistry), products.
Flames, the most visible portion of the fire, are produced in the combustion re ...
,
building
A building or edifice is an enclosed Structure#Load-bearing, structure with a roof, walls and window, windows, usually standing permanently in one place, such as a house or factory. Buildings come in a variety of sizes, shapes, and functions, a ...
, health, and safety
codes
In communications and information processing, code is a system of rules to convert information—such as a letter, word, sound, image, or gesture—into another form, sometimes shortened or secret, for communication through a communication ch ...
require exit signs that are always lit.
Exit signs are intended to be unmistakable and understandable by anyone who can see. In the past, this generally meant exit signs that show the word "EXIT" or the equivalent in the local language; increasingly, exit signs around the world are now pictograms, with or without supplementary text.
History
Early exit signs generally either were made of metal and lit by a nearby
incandescent light bulb
An incandescent light bulb, also known as an incandescent lamp or incandescent light globe, is an electric light that produces illumination by Joule heating a #Filament, filament until it incandescence, glows. The filament is enclosed in a ...
or were a white glass cover with "EXIT" written in red, placed directly in front of a single-bulb
light fixture
A light fixture (US English), light fitting (UK English), or luminaire is an electrical lighting device containing one or more light sources, such as lamps, and all the accessory components required for its operation to provide illumination to ...
. A flaw in these designs was that in a fire the power to the light often failed. In addition, the fixtures, despite their brightness, could be hard to see through smoke. The biggest problem was that the exit sign was hardly distinguishable from an ordinary safety lighting fixture commonly installed above doors in the past. The problem was partially solved by using red-tinted bulbs instead.
Better signs were soon developed that more resembled today's modern exit sign, with an incandescent bulb in a rectangular box that backlit the word "EXIT" on one or both sides. Larger than its predecessors, this version of the exit sign was easier to see. The sign was still only useful as long as mains power remained on.
As
battery-backup systems became smaller and more efficient, some exit signs began to use a dual-power system. Under normal conditions, the exit sign was lit by mains power and the
battery was maintained in a charged state. In the event of a power outage, the battery would supply power to light the sign. Early battery-backup systems were big, heavy, and costly.
Modern systems are lightweight, can be installed virtually anywhere, and are integrated into the fixture, rather than requiring a separate box. As batteries improved, so did the amount of time that a fixture could remain lit on batteries.
While exit signs were more visible due to large letters, even a 60-watt incandescent bulb shining through a plastic or glass cover could appear somewhat dim under certain conditions. Incandescent bulbs are still in use because they are cheap and common, even though they use more electricity and require more or less frequent replacement. Incandescent bulbs lit 24/7 have a greatly extended lifespan compared to ones that cycle on and off. When used in exit signs, they are often operated at a lower voltage than rated, which further extends their lifetime, at the trade-off of reduced light output and greatly reduced energy efficiency.
With the development of
fluorescent lamp
A fluorescent lamp, or fluorescent tube, is a low-pressure mercury-vapor gas-discharge lamp that uses fluorescence to produce visible light. An electric current in the gas excites mercury vapor, to produce ultraviolet and make a phosphor ...
and
light-emitting diode
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corre ...
technology, exit signs could be made even brighter to compensate for the limited visibility in a fire situation, while using less electricity.
Fluorescent lamps are used in the same way as incandescent bulbs, back-lighting both sides of an exit fixture from within.
LED
A light-emitting diode (LED) is a semiconductor device that emits light when current flows through it. Electrons in the semiconductor recombine with electron holes, releasing energy in the form of photons. The color of the light (corresp ...
signs combine a large number of bright light-emitting diodes to illuminate the sign from inside. An exit sign is constantly lit; fluorescent bulbs need to be changed more often than LEDs, although the absence of frequent on/off cycles extends the life of fluorescent lamps significantly. Generally, LEDs have a very long life, and may last for 10 years or more of continuous use, although their brightness may gradually diminish.
Radio-luminescent and
phosphorescent signs that require no electricity have also been developed, and have been used since the 1970s. Radio-luminescence uses the
radioactive decay
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ...
of
tritium
Tritium () or hydrogen-3 (symbol T or H) is a rare and radioactive isotope of hydrogen with a half-life of ~12.33 years. The tritium nucleus (t, sometimes called a ''triton'') contains one proton and two neutrons, whereas the nucleus of the ...
gas to illuminate the sign, while phosphorescence uses light-emitting pigments to glow in the dark. While both of these types of signs meet California State
Fire Marshal
A fire marshal, in the United States and Canada, is often a member of a state, provincial or territorial government, but may be part of a building department or a separate department altogether. Fire marshals' duties vary but usually include ...
standards, electricity is used in the vast majority of signs.
Modern installations
Most exit signs in the world, except in countries such as the United States, Canada, Hong Kong, Philippines, and Singapore, use pictograms. Canada, Singapore, and Hong Kong have changed their safety codes to encourage use of pictograms. The Philippines, which lacks a uniform standard, uses pictograms; signs reading "EXIT", "FIRE EXIT", or "EMERGENCY EXIT"; and combinations of pictograms and text.
In the United States, the
National Fire Protection Association
The National Fire Protection Association (NFPA) is a U.S.-based international nonprofit organization devoted to eliminating death, injury, property damage, and economic loss due to fire, electrical, and related hazards. , the NFPA claims to have 5 ...
(NFPA) defines the standard for exit signs. NFPA 101 - 7.10.3.1 requires textual exit signs for all standard mounted applications; pictograms are allowed instead of or in addition to text if approved by local authorities and compliant with NFPA 170. The NFPA has also approved the ISO pictogram as an option for low-level glow-in-the-dark signs. New York City local law 26 requires these low-level pictograms in all high-rise buildings. In tunnels, the
Transportation Research Board
The Transportation Research Board (TRB) is a division of the National Academies of Sciences, Engineering, and Medicine. TRB's mission is to mobilize expertise, experience, and knowledge to anticipate and solve complex transportation-related challe ...
recommends the ISO symbol.
Newer
Airbus
Airbus SE ( ; ; ; ) is a Pan-European aerospace corporation. The company's primary business is the design and manufacturing of commercial aircraft but it also has separate Airbus Defence and Space, defence and space and Airbus Helicopters, he ...
,
Bombardier CS100, and
Boeing 787 Dreamliner
The Boeing 787 Dreamliner is an American wide-body airliner developed and manufactured by Boeing Commercial Airplanes.
After dropping its unconventional Sonic Cruiser project, Boeing announced the conventional 7E7 on January 29, 2003, wh ...
planes use the new pictogram exit signs, which were approved by the FAA in 2012 and 2014 (depending on aircraft type). The renovated
Government Center subway station in
Boston
Boston is the capital and most populous city in the Commonwealth (U.S. state), Commonwealth of Massachusetts in the United States. The city serves as the cultural and Financial centre, financial center of New England, a region of the Northeas ...
, and the MBTA's newer Type 9 streetcars for the Green Line and new Orange Line and Red Line trains made by
CRRC
CRRC Corporation Limited (known as CRRC) is a Chinese state-owned and publicly traded rolling stock manufacturer. It is the world's largest rolling stock manufacturer in terms of revenue, eclipsing its major competitors of Alstom and Siemens. ...
, use signs bearing "EXIT" in white on a green background beside the ISO pictogram. Recent terminal renovations at the
Albany International Airport have added supplemental ISO pictogram exit signs on terminal way-finding signs near the emergency exits. Parts of the
Corning Museum of Glass
The Corning Museum of Glass is a museum in Corning (city), New York, Corning, New York, United States, dedicated to the art, history, and science of glass. It was founded in 1951 by Corning Incorporated, Corning Glass Works and currently has a ...
use an exclusive variant of the ISO pictogram, pointing to exits, along with textual signs. The
Cherokee Nation
The Cherokee Nation ( or ) is the largest of three list of federally recognized tribes, federally recognized tribes of Cherokees in the United States. It includes people descended from members of the Cherokee Nation (1794–1907), Old Cheroke ...
's Durbin Feeling Language Center uses the ISO pictogram instead of text.
Modern exit signs often can be seen indicating the path to an exit in commercial and large residential buildings that comply with
fire code
Fire safety is the set of practices intended to reduce destruction caused by fire. Fire safety measures include those that are intended to prevent wikt:ignition, the ignition of an uncontrolled fire and those that are used to limit the spread a ...
. Certain circumstances, such as the year a building was built, or a sign that has a unique and historical design blended into its architecture, create exemptions from some of these codes (though in the latter case the lighting and backup lighting system behind the sign will likely be retrofitted to modern requirements). In most situations, the owner of the building is responsible for complying with exit-sign requirements. This is especially true in older buildings that serve as multiple residences, such as apartment buildings, hotels, and campus
dormitories
A dormitory (originated from the Latin word ''dormitorium'', often abbreviated to dorm), also known as a hall of residence, a residence hall (often abbreviated to halls), or a hostel, is a building primarily providing sleeping and residential qu ...
.
Modern fixtures are usually in a rugged plastic or metal housing securely bolted to the wall or ceiling. The signs have the word "EXIT", or a picture representing exit, on both sides. Single-sided signs are also available for wall-mount installations. The signs often have metal or plastic
knock-outs
An electrical enclosure is a Cabinetry, cabinet for Electrical equipment, electrical or electronic equipment to mount switches, Control knob, knobs and Display device, displays and to prevent electrical shock to equipment users and protect t ...
which can optionally be removed so that an arrow is also lit pointing left or right. Modern exit signs are often combined with other safety devices, such as
emergency floodlighting for supplementary area illumination. Modern exit signs are also, to some degree,
flame retardant
Flame retardants are a diverse group of chemicals that are added to manufactured materials, such as plastics and textiles, and surface finishes and coatings. Flame retardants are activated by the presence of an combustion, ignition source and pr ...
.
Exit signs draw a relatively small amount of power, and can generally be added onto any existing electrical circuit without adverse effects. In addition, specialized LED lamps with "candelabra" sized screw-in bases are available to replace the always-on incandescent lamps in older exit signs. This allows the existing fixtures to be easily upgraded to save energy, without the expense of complete replacement.
Most recently, Photoluminescent, Hybrid Photoluminescent and LEC (
light emitting capacitor) exit signs have come to market. Photoluminescent signs consume no power and have an operational life of 30+ years. Hybrid Photoluminescent Exit Signs consume as little as 0.74 W of power. LEC signs are also called
electroluminescent
Electroluminescence (EL) is an optical and electrical phenomenon, in which a material emits light in response to the passage of an electric current or to a strong electric field. This is distinct from black body light emission resulting from ...
(EL), only consuming 1/4 W of power, and have an operational life of 30+ years which far exceeds the typical 10-year life of an LED sign.
Non-compliance with building codes
It is often a serious offence for a building owner or landlord to not comply with the fire/building code in terms of Exit signage. In July 2016, for example, a fire in a
Toronto
Toronto ( , locally pronounced or ) is the List of the largest municipalities in Canada by population, most populous city in Canada. It is the capital city of the Provinces and territories of Canada, Canadian province of Ontario. With a p ...
apartment caused the death of one person and injured many others. An investigation found that Emergency lights and Exit signs were not properly illuminated, and the landlord was fined $21,000 for "not properly illuminating exit signs and having no record of emergency lighting tests", and another $50,000 for other infractions to the code relating to fire doors.
Lighting
Since visibility may be reduced in a fire, due to
smoke
Smoke is an aerosol (a suspension of airborne particulates and gases) emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwante ...
or failure of electric lighting, the sign is often permanently illuminated, usually by one of:
*
Radio-luminescence (or "self-luminous") where a
phosphor
A phosphor is a substance that exhibits the phenomenon of luminescence; it emits light when exposed to some type of radiant energy. The term is used both for fluorescent or phosphorescent substances which glow on exposure to ultraviolet or ...
coating inside a
glass
Glass is an amorphous (non-crystalline solid, non-crystalline) solid. Because it is often transparency and translucency, transparent and chemically inert, glass has found widespread practical, technological, and decorative use in window pane ...
tube glows due to the
beta decay
In nuclear physics, beta decay (β-decay) is a type of radioactive decay in which an atomic nucleus emits a beta particle (fast energetic electron or positron), transforming into an isobar of that nuclide. For example, beta decay of a neutron ...
of
radioactive
Radioactive decay (also known as nuclear decay, radioactivity, radioactive disintegration, or nuclear disintegration) is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is conside ...
tritium
Tritium () or hydrogen-3 (symbol T or H) is a rare and radioactive isotope of hydrogen with a half-life of ~12.33 years. The tritium nucleus (t, sometimes called a ''triton'') contains one proton and two neutrons, whereas the nucleus of the ...
gas sealed into the tube. Radio-luminescent exit signs are prohibited in US
Department of Defense
The United States Department of Defense (DoD, USDOD, or DOD) is an executive department of the U.S. federal government charged with coordinating and supervising the six U.S. armed services: the Army, Navy, Marines, Air Force, Space Force, ...
installations.
*
Photoluminescence
Photoluminescence (abbreviated as PL) is light emission from any form of matter after the absorption of photons (electromagnetic radiation). It is one of many forms of luminescence (light emission) and is initiated by photoexcitation (i.e. phot ...
(or "glow in the dark") use
phosphorescence
Phosphorescence is a type of photoluminescence related to fluorescence. When exposed to light (radiation) of a shorter wavelength, a phosphorescent substance will glow, absorbing the light and reemitting it at a longer wavelength. Unlike fluor ...
, where light absorbed earlier from the surroundings is slowly re-emitted
* Electric lighting, with a local
rechargeable power source
* Electric lighting, with the building's emergency lighting circuits providing
back-up power from a
UPS or a
generator in case normal power fails
Color and design
In most regions, including
China
China, officially the People's Republic of China (PRC), is a country in East Asia. With population of China, a population exceeding 1.4 billion, it is the list of countries by population (United Nations), second-most populous country after ...
, the
European Union
The European Union (EU) is a supranational union, supranational political union, political and economic union of Member state of the European Union, member states that are Geography of the European Union, located primarily in Europe. The u ...
,
Japan
Japan is an island country in East Asia. Located in the Pacific Ocean off the northeast coast of the Asia, Asian mainland, it is bordered on the west by the Sea of Japan and extends from the Sea of Okhotsk in the north to the East China Sea ...
, and
South Korea
South Korea, officially the Republic of Korea (ROK), is a country in East Asia. It constitutes the southern half of the Korea, Korean Peninsula and borders North Korea along the Korean Demilitarized Zone, with the Yellow Sea to the west and t ...
exit signs have
green
Green is the color between cyan and yellow on the visible spectrum. It is evoked by light which has a dominant wavelength of roughly 495570 nm. In subtractive color systems, used in painting and color printing, it is created by a com ...
lettering. (In this color scheme, red is reserved to indicate prohibited activities.) In
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
,
Canada
Canada is a country in North America. Its Provinces and territories of Canada, ten provinces and three territories extend from the Atlantic Ocean to the Pacific Ocean and northward into the Arctic Ocean, making it the world's List of coun ...
,
New Zealand
New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
, and most European countries, pictograms are used in place of the word "exit". European sign
directive 92/58/EEC of 24 June 1992 indicates that the signs should be green in color to indicate a safe place of exit. BS EN 1838:1999 and BS 5266-7:1999 also govern emergency lighting applications.
In the United States, exit signs can be red or green, but traditionally they have been red. Many states or cities have enacted building codes that specify the sign color. For example, in
Baltimore
Baltimore is the most populous city in the U.S. state of Maryland. With a population of 585,708 at the 2020 census and estimated at 568,271 in 2024, it is the 30th-most populous U.S. city. The Baltimore metropolitan area is the 20th-large ...
,
Salt Lake City
Salt Lake City, often shortened to Salt Lake or SLC, is the capital and most populous city of the U.S. state of Utah. It is the county seat of Salt Lake County, the most populous county in the state. The city is the core of the Salt Lake Ci ...
, and
Portland, Oregon
Portland ( ) is the List of cities in Oregon, most populous city in the U.S. state of Oregon, located in the Pacific Northwest region. Situated close to northwest Oregon at the confluence of the Willamette River, Willamette and Columbia River, ...
, green is required. New York City,
Rhode Island
Rhode Island ( ) is a state in the New England region of the Northeastern United States. It borders Connecticut to its west; Massachusetts to its north and east; and the Atlantic Ocean to its south via Rhode Island Sound and Block Is ...
, and
Chicago
Chicago is the List of municipalities in Illinois, most populous city in the U.S. state of Illinois and in the Midwestern United States. With a population of 2,746,388, as of the 2020 United States census, 2020 census, it is the List of Unite ...
(along with the rest of
Illinois
Illinois ( ) is a U.S. state, state in the Midwestern United States, Midwestern United States. It borders on Lake Michigan to its northeast, the Mississippi River to its west, and the Wabash River, Wabash and Ohio River, Ohio rivers to its ...
) require that exit signs be red.
New and renovated buildings in Canada are required to use the international standard green "running man" pictogram. The 1995 Canadian
national building code required "red letters on a contrasting background or white letters on a red background ... spelling EXIT or SORTIE"; however, the 2010 Code calls for a switch from the red EXIT signs to the green "running-man" signs.
The national building code informs provincial and municipal building codes but does not have legal status itself. Most Canadian jurisdictions require the international green "running-man" pictogram; however, some have allowed red "EXIT" signs to be maintained in older properties so long as one style is used consistently throughout the building.
Green fluorescent signs can be seen better in dark conditions than other colours, as the human
rod cell
Rod cells are photoreceptor cells in the retina of the eye that can function in lower light better than the other type of visual photoreceptor, cone cells. Rods are usually found concentrated at the outer edges of the retina and are used in ...
is more sensitive to these wavelengths.
Newly installed exit signs in
Australia
Australia, officially the Commonwealth of Australia, is a country comprising mainland Australia, the mainland of the Australia (continent), Australian continent, the island of Tasmania and list of islands of Australia, numerous smaller isl ...
and
New Zealand
New Zealand () is an island country in the southwestern Pacific Ocean. It consists of two main landmasses—the North Island () and the South Island ()—and List of islands of New Zealand, over 600 smaller islands. It is the List of isla ...
are green with a white "running man" ISO 7010 figure. Previously, green-written 'EXIT' signs were standard.
Accessible designs
There is a trend towards providing a more
accessible, socially inclusive exit sign design based on
universal design
Universal design is the design of buildings, products or environments to make them accessible to people, regardless of age, disability, or other factors. It emerged as a rights-based, anti-discrimination measure, which seeks to create design ...
principles, including consideration for people with
disabilities
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, developmental, intellectual, mental, physica ...
in the overall exit sign strategy for a building or facility.
The Accessible Exit Sign Project, which started in Australia in 2014 and has spread to New Zealand and the United States, is an international awareness campaign that promotes the need for an accessible means of egress. Advocates propose that appropriate exit signage to identify the accessible means of egress is a critical component to successful emergency planning for any building.
The proposed new exit sign design features an "Accessible Means of Egress Icon", which includes an adaptation of the "running man" symbol with a new wheelchair symbol. The design is considered an enhanced version of the
ISO 7010
ISO 7010 is an International Organization for Standardization technical standard for graphical hazard symbols on hazard and safety signs, including those indicating emergency exits. It uses colours and principles set out in ISO 3864 for the ...
and
ISO 21542 accessible exit sign that shows the "running man" and
International Symbol of Access at the end of the sign. The universally inclusive design with the "running man" and "Accessible Means of Egress Icon" wheelchair symbol essentially share the same upper torso, and the design shows the two moving through the door together.
The Global Alliance on Accessible Technologies and Environments (GAATES) has stated that the introduction of the "Accessible Means of Egress Icon" onto exit signage changes the current discriminatory approach to emergency exit signs and presents a fully inclusive design.
"The combined ‘Running Man’ and ‘Accessible Means of Egress Icon’
��are working together to escape the building. They move in unison, display the same urgency and motion and appear to be travelling at the same speed. Their heads are forward, showing their haste. Arms are extended and motioning back and forth as they move through the doorway."
The accessible exit signs are now being produced in Australia, New Zealand, United States, and United Kingdom, also featuring
braille
Braille ( , ) is a Tactile alphabet, tactile writing system used by blindness, blind or visually impaired people. It can be read either on embossed paper or by using refreshable braille displays that connect to computers and smartphone device ...
and
tactile lettering suitable for people that have low vision or are blind. The design is intended to show where wheelchair accessible exit routes, evacuation lifts, evacuation devices and areas of refuge are located. The concept also provides more intuitive building design to assist people that are blind or have low vision to locate an exit.
The design also meets the intent of the
UN Convention on the Rights of Persons with Disabilities which requires signatory countries to consider the need for universal design in buildings.
See also
*
Emergency light
References
External links
*
{{Fire protection
Safety equipment
Signage