Chair - AbsoluteAstronomy.com

A chair is a stable, raised surface used to sit on, commonly for use by one person. Chairs are most often supported by four legs and have a back; however, a chair can have three legs (in a triangle shape) or could have a different shape depending on the criteria of the chair specifications. A chair without a back or arm rests is a stool, or when raised up, a bar stool

Bar stool

Bar stools are a type of tall stool, often with a foot rest, which because of their height and narrowness are designed for seating in a public house or bar...

. A chair with arms is an armchair and with folding action and inclining footrest, a recliner. A permanently fixed chair in a train or theater

Theater (structure)

A theater or theatre is a structure where theatrical works or plays are performed or other performances such as musical concerts may be produced. While a theater is not required for performance , a theater serves to define the performance and audience spaces...

is a seat or airline seat

Airline seat

An airline seat is a chair on an airliner in which passengers are accommodated for the duration of the journey. Such seats are usually arranged in rows running across the airplane's fuselage...

; when riding, it is a saddle

Saddle

A saddle is a supportive structure for a rider or other load, fastened to an animal's back by a girth. The most common type is the equestrian saddle designed for a horse, but specialized saddles have been created for camels and other creatures...

and bicycle saddle

Bicycle saddle

A bicycle saddle, often called a seat, is one of three contact points on an upright bicycle, the others being the pedals and the handlebars.The bicycle saddle has been known as such since the bicycle evolved from the draisine, a forerunner of the bicycle...

, and for an automobile, a car seat

Car seat

A car seat is the chair used in automobiles. Most car seats are made from inexpensive but durable material in order to withstand as much use as possible.-Ergonomy: Lumbar and thigh support:...

or infant car seat

Infant car seat

An infant safety seat, also known as a child safety seat, a child restraint system, a restraint car seat, and, ambiguously, commonly known as a car seat, is a restraint which is secured to the seat of an automobile equipped with safety harnesses to hold an infant or small stature people in the...

. With wheels it is a wheelchair

Wheelchair

A wheelchair is a chair with wheels, designed to be a replacement for walking. The device comes in variations where it is propelled by motors or by the seated occupant turning the rear wheels by hand. Often there are handles behind the seat for someone else to do the pushing...

and when hung from above, a swing

Swing (seat)

A swing is a hanging seat, usually found at playgrounds for children, a circus for acrobats, or on a porch for relaxing. The seat of a swing may be suspended from chains or ropes. Once a swing is in motion it continues to oscillate like a pendulum until external interference or drag brings it to a...

.

The design may be made of porous materials, or be drilled

Drilling

Drilling is a cutting process that uses a drill bit to cut or enlarge a hole in solid materials. The drill bit is a multipoint, end cutting tool...

with holes for decoration; a low back or gaps can provide ventilation

Ventilation (architecture)

Ventilating is the process of "changing" or replacing air in any space to provide high indoor air quality...

. The back may extend above the height of the occupant's head, which can optionally contain a headrest

Headrest

In an automobile, head restraints are attached or integrated into the top of the seats in each seating position to limit the rearward movement of an adult occupant's head relative to his torso in a crash, so as to reduce the danger of whiplash or other injury to the cervical vertebrae...

.

A chair for more than one person is a couch, sofa, settee, or "loveseat"

Couch

A couch, also called a sofa, is an item of furniture designed to seat more than one person, and providing support for the back and arms. Typically, it will have an armrest on either side. In homes couches are normally found in the family room, living room, den or the lounge...

; or a bench

Bench (furniture)

A bench is a piece of furniture, on which several people may sit at the same time. Benches are typically made of wood, but may also be made of metal, stone, or synthetic materials. Many benches have arm and back rests; some have no back rest and can be sat on from either side. In public areas,...

. A separate footrest for a chair is known as an ottoman

Ottoman (furniture)

An ottoman is a piece of furniture consisting of a padded, upholstered seat or bench having neither back nor arms, often used as a stool or footstool, or in some cases as an improvised coffee table. Ottomans are often sold as coordinating furniture with armchairs or gliders.An ottoman can also be...

, hassock or pouffe.

History of the chair

The chair is of extreme antiquity and simplicity, although for many centuries and indeed for thousands of years it was an article of state and dignity rather than an article of ordinary use. "The chair" is still extensively used as the emblem of authority in the House of Commons

House of Commons

The House of Commons is the name of the elected lower house of the bicameral parliaments of the United Kingdom and Canada and historically was the name of the lower houses of Ireland and North Carolina...

in the United Kingdom and Canada, and in many other settings. Committees, boards of directors, and academic departments all have a 'chairman'. Endowed professorships are referred to as chairs. It was not, in fact, until the 16th century that it became common anywhere. The chest

Chest (furniture)

A chest is one of the oldest forms of furniture. It is typically a rectangular structure with four walls and a liftable lid, for storage. The interior space may be subdivided...

, the bench

Bench (furniture)

and the stool were until then the ordinary seats of everyday life, and the number of chairs which have survived from an earlier date is exceedingly limited; most of such examples are of ecclesiastical or seigneurial origin. Our knowledge of the chairs of remote antiquity

Ancient history

Ancient history is the study of the written past from the beginning of recorded human history to the Early Middle Ages. The span of recorded history is roughly 5,000 years, with Cuneiform script, the oldest discovered form of coherent writing, from the protoliterate period around the 30th century BC...

is derived almost entirely from monuments, sculpture and paintings.

In ancient Egypt

Egypt

Egypt , officially the Arab Republic of Egypt, Arabic: , is a country mainly in North Africa, with the Sinai Peninsula forming a land bridge in Southwest Asia. Egypt is thus a transcontinental country, and a major power in Africa, the Mediterranean Basin, the Middle East and the Muslim world...

chairs appear to have been of great richness and splendor. Fashioned of ebony and ivory, or of carved and gilded wood

Wood

Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

, they were covered with costly materials, magnificent patterns and supported upon representations of the legs of beasts or the figures of captives. During Tang dynasty

Tang Dynasty

The Tang Dynasty was an imperial dynasty of China preceded by the Sui Dynasty and followed by the Five Dynasties and Ten Kingdoms Period. It was founded by the Li family, who seized power during the decline and collapse of the Sui Empire...

(618 - 907 AD), a higher seat first started to appear amongst the Chinese elite and their usage soon spread to all levels of society. By the 12th century seating on the floor was rare in China, unlike in other Asian countries where the custom continued, and the chair, or more commonly the stool, was used in the vast majority of houses throughout the country.

In Europe, it was owing in great measure to the Renaissance

Renaissance

The Renaissance was a cultural movement that spanned roughly the 14th to the 17th century, beginning in Italy in the Late Middle Ages and later spreading to the rest of Europe. The term is also used more loosely to refer to the historical era, but since the changes of the Renaissance were not...

that the chair ceased to be a privilege of state, and became a standard item of furniture for anyone who could afford to buy it. Once the idea of privilege faded the chair speedily came into general use. We find almost at once that the chair began to change every few years to reflect the fashions of
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The 20th century saw an increasing use of technology in chair construction with such things as all-metal folding chairs, metal-legged chairs, the Slumber Chair, moulded plastic chairs and ergonomic chairs. The recliner became a popular form, at least in part due to radio and television, and later a two-part. The modern movement of the 1960s produced new forms of chairs: the butterfly chair

Butterfly chair

A butterfly chair, also known as a BKF chair, is a style of chair featuring a folding frame and a large cloth sling hung from the frames highest points. This design is popular for portable recreational seating.-History:...

, bean bags, and the egg-shaped pod chair. Technological advances led to molded plywood

Plywood

Plywood is a type of manufactured timber made from thin sheets of wood veneer. It is one of the most widely used wood products. It is flexible, inexpensive, workable, re-usable, and can usually be locally manufactured...

and wood laminate

Laminate

A laminate is a material that can be constructed by uniting two or more layers of material together. The process of creating a laminate is lamination, which in common parlance refers to the placing of something between layers of plastic and gluing them with heat and/or pressure, usually with an...

chairs, as well as chairs made of leather

Leather

Leather is a durable and flexible material created via the tanning of putrescible animal rawhide and skin, primarily cattlehide. It can be produced through different manufacturing processes, ranging from cottage industry to heavy industry.-Forms:...

or polymers. Mechanical technology incorporated into the chair enabled adjustable chairs, especially for office

Office chair

An office chair, or desk chair, is a type of chair that is designed for use at a desk in an office. It should be comfortable and adjustable and can swivel 360 degrees.-History:...

use. Motors embedded in the chair resulted in massage chair

Massage chair

Massage chairs come in two main types.-Traditional massage chairs:Ergonomically designed chairs for positioning a person who will be receiving a massage, similar in function to a massage table. Chairs may be either stationary or portable models. Different chairs have different features, and many...

Design and ergonomics

Chair design considers intended usage, ergonomics (how comfortable it is for the occupant), as well as non-ergonomic functional requirements such as size, stackability, foldability, weight, durability, stain resistance and artistic design. Intended usage determines the desired seating position. "Task chairs", or any chair intended for people to work at a desk or table, including dining chairs, can only recline very slightly; otherwise the occupant is too far away from the desk or table. Dental chairs are necessarily reclined. Easy chairs for watching television or movies are somewhere in between depending on the height of the screen.

Ergonomic design distributes the weight of the occupant to various parts of the body

Human body

The human body is the entire structure of a human organism, and consists of a head, neck, torso, two arms and two legs.By the time the human reaches adulthood, the body consists of close to 100 trillion cells, the basic unit of life...

. A seat that is higher results in dangling feet and increased pressure on the underside of the knees ("popliteal fold

Popliteal fossa

The popliteal fossa is a shallow depression located at the back of the knee joint. The bones of the popliteal fossa are the femur and the tibia.-Boundaries:The boundaries of the fossa are:-Roof:...

"). It may also result in no weight on the feet which means more weight elsewhere. A lower seat may shift too much weight to the "seat bones" ("ischial tuberosities").

A reclining seat and back will shift weight to the occupant's back. This may be more comfortable for some in reducing weight on the seat area, but may be problematic for others who have bad backs. In general, if the occupant is supposed to sit for a long time, weight needs to be taken off the seat area and thus "easy" chairs intended for long periods of sitting are generally at least slightly reclined. However, reclining may not be suitable for chairs intended for work or eating at table.

The back of the chair will support some of the weight of the occupant, reducing the weight on other parts of the body. In general, backrests come in three heights: Lower back backrests support only the lumbar

Lumbar

In tetrapod anatomy, lumbar is an adjective that means of or pertaining to the abdominal segment of the torso, between the diaphragm and the sacrum ...

region. Shoulder height backrests support the entire back and shoulders

Shoulders

Shoulders is drinking game that involves players competing in a fast paced game attempting to "count" to 21.-Game play:*The game begins with a player slapping his left/right shoulder, this starts the count at 1....

. Headrest

Headrest

s support the head as well and are important in vehicles for preventing "whiplash

Whiplash (medicine)

Whiplash is a non-medical term describing a range of injuries to the neck caused by or related to a sudden distortion of the neck associated with extension. The term "whiplash" is a colloquialism...

" neck injuries in rear-end collisions where the head is jerked back suddenly. Reclining chairs typically have at least shoulder height backrests to shift weight to the shoulders instead of just the lower back.

Some chairs have foot rests. A stool

Bar stool

Bar stools are a type of tall stool, often with a foot rest, which because of their height and narrowness are designed for seating in a public house or bar...

or other simple chair may have a simple straight or curved bar near the bottom for the sitter to place his or her feet on.

Some chairs have two curved bands of wood (also known as rockers) attached to the bottom of the legs. They are called rocking chair

Rocking chair

A rocking chair or rocker is a type of chair with two curved bands of wood attached to the bottom of the legs . The chair contacts with the floor at only two points, giving the occupant the ability to rock back and forth by shifting his/her weight or pushing lightly with his/her feet...

s.
A kneeling chair

Kneeling chair

A kneeling chair is a type of chair for sitting in a position with the thighs dropped to an angle of about 60 to 70 degrees from vertical , with some of the body's weight supported by the shins. The original kneeling chair was the Balans chair, which was developed in 1979 by Hans Christian...

adds an additional body part, the knees, to support the weight of the body. A sit-stand chair distributes most of the weight of the occupant to the feet. Many chairs are padded or have cushion

Cushion

A cushion is a soft bag of some ornamental material, stuffed with wool, hair, feathers, polyester staple fiber, non-woven material, or even paper torn into fragments. It may be used for sitting or kneeling upon, or to soften the hardness or angularity of a chair or couch...

s. Padding can be on the seat of the chair only, on the seat and back, or also on any arm rests and/or foot rest the chair may have. Padding will not shift the weight to different parts of the body (unless the chair is so soft that the shape is altered). However, padding does distribute the weight by increasing the area of contact between the chair and the body. A hard wood chair feels hard because the contact point between the occupant and the chair is small. The same body weight over a smaller area means greater pressure on that area. Spreading the area reduces the pressure at any given point. In lieu of padding, flexible materials, such as wicker, may be used instead with similar effects of distributing the weight. Since most of the body weight is supported in the back of the seat, padding there should be firmer than the front of the seat which only has the weight of the legs to support. Chairs that have padding that is the same density front and back will feel soft in the back area and hard to the underside of the knees.

There may be cases where padding is not desirable. For example, in chairs that are intended primarily for outdoor use. Where padding is not desirable, contouring may be used instead. A contoured seat pan attempts to distribute weight without padding. By matching the shape of the occupant's buttocks

Buttocks

The buttocks are two rounded portions of the anatomy, located on the posterior of the pelvic region of apes and humans, and many other bipeds or quadrupeds, and comprise a layer of fat superimposed on the gluteus maximus and gluteus medius muscles. Physiologically, the buttocks enable weight to...

, weight is distributed and maximum pressure is reduced.

Actual chair dimensions are determined by measurements of the human body or anthropometric

Anthropometry

Anthropometry refers to the measurement of the human individual...

measurements. The two most relevant anthropometric measurement for chair design is the popliteal height

Popliteal height

For someone seated, the popliteal height is the distance from the underside of the foot to the underside of the thigh at the knees. It is sometimes called the "stool height"...

and buttock popliteal

Buttock popliteal

For someone seated, the buttock popliteal length is the horizontal distance from the rearmost part of the buttocks to the back of the lower leg. This anthropometric measurement is used to determine seat depth. Mass produced chairs typically use a depth of 38 to 43 cm...

length.

For someone seated, the popliteal height is the distance from the underside of the foot to the underside of the thigh at the knees. It is sometimes called the "stool height." The term "sitting height" is reserved for the height to the top of the head when seated. For American men, the median popliteal height is 16.3 inches (414 mm) and for American women it is 15 inches (381 mm) http://web.archive.org/web/20090330084142/http://www.cdc.gov/niosh/pot_anth.html. The popliteal height, after adjusting for heels, clothing and other issues is used to determine the height of the chair seat. Mass produced chairs are typically 17 inches (431.8 mm) high.

For someone seated, the buttock popliteal length is the horizontal distance from the back most part of the buttocks to the back of the lower leg. This anthropometric measurement is used to determine the seat depth. Mass produced chairs are typically 15-17 inches deep.

Additional anthropometric measurements may be relevant to designing a chair. Hip breadth is used for chair width and armrest width. Elbow rest height is used to determine the height of the armrests. The buttock-knee length is used to determine "leg room" between rows of chairs. "Seat pitch" is the distance between rows of seats. In some airplanes and stadiums the leg room (the seat pitch less the thickness of the seat at thigh level) is so small that it is sometimes insufficient for the average person.

For adjustable chairs, such as an office chair

Office chair

An office chair, or desk chair, is a type of chair that is designed for use at a desk in an office. It should be comfortable and adjustable and can swivel 360 degrees.-History:...

, the aforementioned principles are applied in adjusting the chair to the individual occupant.

Caster wheels are attached to the feet of chairs to give more mobility

Gas spring
Gas spring
A gas spring is a type of spring that, unlike a typical metal spring, uses a compressed gas, contained in a cylinder and compressed by a piston, to exert a force. Gas springs are used in automobiles, where they are incorporated into the design of struts that support the weight of hatchback doors...

s are attached to the body of the chair in order to give height adjustment and more comfort to the user

Armrests

A chair may or may not have armrests; chairs with armrests are termed armchairs. In French

French language

French is a Romance language spoken as a first language in France, the Romandy region in Switzerland, Wallonia and Brussels in Belgium, Monaco, the regions of Quebec and Acadia in Canada, and by various communities elsewhere. Second-language speakers of French are distributed throughout many parts...

, a distinction is made between fauteuil and chaise, the terms for chairs with and without armrests, respectively. If present, armrests will support part of the body weight through the arms if the arms are resting on the armrests. Armrests further have the function of making entry and exit from the chair easier (but from the side it becomes more difficult). Armrests should support the forearm and not the sensitive elbow area. Hence in some chair designs, the armrest is not continuous to the chair back, but is missing in the elbow area

Area

Area is a quantity that expresses the extent of a two-dimensional surface or shape in the plane. Area can be understood as the amount of material with a given thickness that would be necessary to fashion a model of the shape, or the amount of paint necessary to cover the surface with a single coat...

.

A couch

Couch

, bench

Bench (furniture)

, or other arrangement of seats next to each other may have armrest at the sides and/or arm rests in between. The latter may be provided for comfort, but also for privacy

Privacy

Privacy is the ability of an individual or group to seclude themselves or information about themselves and thereby reveal themselves selectively...

e.g. in public transport

Public transport

Public transport is a shared passenger transportation service which is available for use by the general public, as distinct from modes such as taxicab, car pooling or hired buses which are not shared by strangers without private arrangement.Public transport modes include buses, trolleybuses, trams...

and other public places, and to prevent lying on the bench. Arm rests reduce both desired and undesired proximity

Proxemics

Proxemics is the study of measurable distances between people as they interact. The term was introduced by anthropologist Edward T. Hall in 1966...

. A loveseat in particular, has no armrest in between.

See also seats in movie theaters, and pictures of benches with and without arm rests.

Chair seats

Chair seats vary widely in construction and may or may not match construction of the chair's back (backrest).

Some systems include:

center seats where a solid material forms the chair seat.
- Solid wood, may or may not be shaped to human contours.
- Wood slats, often seen on outdoor chairs
- Padded leather, generally a flat wood base covered in padding and contained in soft leather
- Stuffed fabric, similar to padded leather
- Metal seats of solid or open design
- Molded plastic
- Stone, often marble
  Marble
  Marble is a metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite.Geologists use the term "marble" to refer to metamorphosed limestone; however stonemasons use the term more broadly to encompass unmetamorphosed limestone.Marble is commonly used for...
Open center seats where a soft material is attached to the tops of chair legs or between stretchers to form the seat.
- Wicker, woven to provide a surface with give to it
- Leather, may be tooled with a design
- Fabric, simple covering without support
- Tape, wide fabric tape woven into seat, seen in lawn chairs and some old chairs
- Caning
  Caning (furniture)
  In the context of furniture, caning is a method of weaving chair seats and other furniture. Caning material is wicker such as cane, or it is derived from the skin of rattan vines native to Indonesia, the Philippines and Malaysia. Some vines reach 500 feet in length. One of the earliest woven chair...
  
  , woven from rush
  Juncaceae
  Juncaceae, the rush family, are a monocotyledonous family of flowering plants. There are eight genera and about 400 species. Members of the Juncaceae are slow-growing, rhizomatous, herbaceous plants, and they may superficially resemble grasses. They often grow on infertile soils in a wide range...
  
  , reed
  Phragmites
  Phragmites, the Common reed, is a large perennial grass found in wetlands throughout temperate and tropical regions of the world. Phragmites australis is sometimes regarded as the sole species of the genus Phragmites, though some botanists divide Phragmites australis into three or four species...
  
  , rawhide, heavy paper, strong grasses, cattails to form the seat, often in elaborate patterns
- Splint, ash
  Ash tree
  Fraxinus is a genus flowering plants in the olive and lilac family, Oleaceae. It contains 45-65 species of usually medium to large trees, mostly deciduous though a few subtropical species are evergreen. The tree's common English name, ash, goes back to the Old English æsc, while the generic name...
  
  , oak
  Oak
  An oak is a tree or shrub in the genus Quercus , of which about 600 species exist. "Oak" may also appear in the names of species in related genera, notably Lithocarpus...
  
  or hickory
  Hickory
  Trees in the genus Carya are commonly known as hickory, derived from the Powhatan language of Virginia. The genus includes 17–19 species of deciduous trees with pinnately compound leaves and big nuts...
  
  strips are woven
- Metal, Metal mesh or wire woven to form seat

Standards and specifications

Design considerations for chairs have been codified into standards. ISO 9241

ISO 9241

ISO 9241 is a multi-part standard from the International Organization for Standardization covering ergonomics of human-computer interaction. It is managed by the ISO...

, "Ergonomic requirements for office work with visual display terminals (VDTs) -- Part 5: Workstation layout and postural requirements" is the most common one for modern chair design.

There are multiple specific standards for different types of chairs. Dental chairs are specified by ISO 6875. Bean bag chairs are specified by ANSI

American National Standards Institute

The American National Standards Institute is a private non-profit organization that oversees the development of voluntary consensus standards for products, services, processes, systems, and personnel in the United States. The organization also coordinates U.S. standards with international...

standard ASTM F1912-98 http://webstore.ansi.org/ansidocstore/product.asp?sku=ASTM+F1912%2D98. ISO 7174 specifies stability of rocking and tilting chairs. ASTM F1858-98 specifies plastic lawn chairs. ASTM E1822-02b defines the combustibility of chairs when they are stacked.

The Business and Institutional Furniture Manufacturer's Association (BIFMA)http://www.bifma.org defines BIFMA X5.1 for testing of commercial-grade chairs. It specifies things like http://www.lifetime.com/TablesAndChairs/bifma.pdf:

chair back strength of 150 pounds (68 kg)
chair stability if weight is transferred completely to the front or back legs
leg strength of 75 pounds (34 kg) applied one inch (25 mm) from the bottom of the leg
seat strength of 225 pounds (102 kg) dropped from six inches (150 mm) above the seat
seat cycle strength of 100,000 repetitions of 125 pounds (57 kg) dropped from 2 inches (50 mm) above the seat

The specification further defines heavier "proof" loads that chairs must withstand. Under these higher loads, the chair may be damaged, but it must not fail catastrophically.

Large institutions that make bulk purchases will reference these standards within their own even more detailed criteria for purchase.
http://www.tbpc.state.tx.us/spec_lib/425/specs/06-12a.html Governments will often issue standards for purchases by government agencies (e.g. Canada's Canadian General Standards Board CAN/CGSB 44.15M http://www.techstreet.com/cgi-bin/detail?product_id=23061 on "Straight Stacking Chair, Steel" or CAN/CGSB 44.232-2002 on "Task Chairs for Office Work with Visual Display Terminal").

Chairs may be rated by the length of time that they may be used comfortably — an 8-hour chair, a 24-hour chair, and so on. Such chairs are specified for tasks which require extended periods of sitting, such as for receptionists or supervisors of a control panel.

Accessories

In place of a built-in footrest, some chairs come with a matching ottoman

Ottoman (furniture)

. An ottoman is a short stool intended to be used as a footrest but can sometimes be used as a stool. If matched to a glider, the ottoman may be mounted on swing arms so that the ottoman rocks back and forth with the main glider.

A chair cover is a temporary fabric cover for a side chair. They are typically rented for formal events such as wedding receptions to increase the attractiveness of the chairs and decor. The chair covers may come with decorative chair ties, a ribbon to be tied as a bow behind the chair. Covers for sofas and couches are also available for homes with small children and pets. In the second half of 20th century, some people used custom clear plastic covers for expensive sofas and chairs to protect them.

Chair pads are cushions for chairs. They contain cotton or foam for padding. Some are decorative. In cars, they may be used to increase the height of the driver. Orthopedic backrests provide support for the back. Some manufacturers have patents on their designs and are recognized by medical associations as beneficial http://www.physiotherapy.ca/?WCE=C=47%7CK=223736 http://www.cartalk.com/content/columns/Archive/1996/June/05.html http://www.chiroeco.com/article/1996/1996.php3?article=050696f2&menu=050696. Car seats sometimes have built-in and adjustable lumbar supports. These can also be used on kitchen chairs.

Chair mats are mats meant to cover carpet or hardwood flooring. They are usually made from plastic. This allows chairs on wheels to roll easily over the carpet and/or protects the carpet or floor. They come in various shapes, some specifically sized to fit partially under a desk.

Remote control bags can be draped over the arm of easy chairs or sofas and used to hold remote controls. They are counter-weighted so as to not slide off the arms under the weight of the remote control.

Chair glides are attached to the feet of chairs to prevent them from scratching or snagging on the floor.

Chairs as sculptural and art forms

In 2001, Steve Mann

Steve Mann

Steven Mann , is a tenured professor at the Department of Electrical and Computer Engineering at the University of Toronto.-Education:...

exhibited a chair sculpture at San Francisco Art Institute. The chair had spikes that retracted when a credit card was inserted to download a seating license.
Later other museums and galleries were equipped with the Pay to Sit chair, with a global central seating license server located in Toronto. Patrons anywhere in the world could each receive one free seat license. The first seating session was free, with a database of persons who'd already used their free session.

In language

A film or a story is said to keep you on the edge of your seat, if it is suspenseful or engaging.
If you nearly fell off your chair, it was because you were very surprised.
An orchestra awards a musician a chair or seat based on ability. The best player in a particular section will receive "first chair," or the "principal seat." It is also common for this position to be known as 'first stand,' a reference to the portable lectern on which the musicians put their sheet music. However, the person who is first chair in the first violin section is usually referred to as the concertmaster
Concertmaster
The concertmaster/mistress is the spalla or leader, of the first violin section of an orchestra. In the UK, the term commonly used is leader...

in the USA
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

or leader
Concertmaster
The concertmaster/mistress is the spalla or leader, of the first violin section of an orchestra. In the UK, the term commonly used is leader...

in the UK
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

.
Musical chairs
Musical chairs
Musical chairs is a game played by a group of people , often in an informal setting purely for entertainment such as a birthday party...

is a common party game, and a colloquial expression to describe people shuffling from seat to seat, or around different locations.
In American slang, to say someone has gotten "the chair" is to say that they have been executed by an electric chair
Electric chair
Execution by electrocution, usually performed using an electric chair, is an execution method originating in the United States in which the condemned person is strapped to a specially built wooden chair and electrocuted through electrodes placed on the body...

.
To be on its last leg is an expression that stems from the practice of sawing the ends of chair legs off in previous centuries. It means that it is decrepit and nearing the end of its serviceability.

History of the chair

Design and ergonomics

Armrests

Chair seats

Standards and specifications

Accessories

Chairs as sculptural and art forms

In language

See also

Further reading