Chair
A chair is a type of seat, typically designed for one person and consisting of one or more legs, a flat or slightly angled seat and a back-rest. They may be made of wood, metal, or synthetic materials, and may be padded or upholstered in various colors and fabrics.
Chairs vary in design. An armchair has
armrests fixed to the seat; a recliner is
upholstered and features a mechanism that lowers the chair's back and raises
into place a footrest; a rocking
chair has legs fixed to two long curved slats; and a wheelchair has
wheels fixed to an axis under the seat.
Etymology
Chair comes from the early 13th-century English
word chaere, from Old French chaiere ("chair,
seat, throne"), from Latin cathedra ("seat").
History
The chair has been used since antiquity, although for many
centuries it was a symbolic article of state and dignity rather than an article
for ordinary use. "The chair" is still used as the emblem of
authority in the House of Commons in the United Kingdom and Canada, and
in many other settings. In keeping with this historical connotation of the
"chair" as the symbol of authority, committees, boards of directors,
and academic departments all have a 'chairman' or 'chair'. Endowed
professorships are referred to as chairs. It was not until the 16th
century that chairs became common. Until then, people sat on chests, benches,
and stools, which were the ordinary seats of everyday life. The number of
chairs which have survived from an earlier date is exceedingly limited; most
examples are of ecclesiastical, seigneurial or feudal origin.
Chairs were in existence since at least the Early Dynastic Period of Egypt (c.
3100 BC). They were covered with cloth or leather, were
made of carved wood, and were much lower than today's chairs – chair seats were
sometimes only 10 inches (25 cm) high. In ancient Egypt, chairs appear
to have been of great richness and splendor. Fashioned of ebony and ivory, or of carved
and gilded wood, they were
covered with costly materials, magnificent patterns and supported upon
representations of the legs of beasts or the figures of captives. Generally
speaking, the higher ranked an individual was, the taller and more sumptuous
was the chair he sat on and the greater the honor. On state occasions, the
pharaoh sat on a throne, often with a little footstool in front of it.
The average Egyptian family seldom had chairs, and if they
did, it was usually only the master of the household who sat on a chair. Among
the better off, the chairs might be painted to look like the ornate inlaid and
carved chairs of the rich, but the craftsmanship was usually poor.
The earliest images of chairs in China are from 6th-century
Buddhist murals and stele, but the practice of sitting in
chairs at that time was rare. It was not until the 12th century that chairs
became widespread in China. Scholars disagree on the reasons for the adoption of the
chair. The most common theories are that the chair was an outgrowth of
indigenous Chinese furniture, that it evolved from a camp stool imported from
Central Asia, that it was introduced to China by Christian missionaries in the
7th century, and that the chair came to China from India as a form of Buddhist
monastic furniture. In modern China, unlike Korea or Japan, it is no
longer common to sit at floor level.
In Europe, it was owing in great measure to the Renaissance 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. Almost at once the chair began
to change every few years to reflect the fashions of the day.
Thomas Edward Bowdich visited the main
Palace of the Ashanti Empire in 1819, and observed chairs
engrossed with gold in the empire. In the 1880s, chairs became more common
in American households and usually there was a chair provided for every family
member to sit down to dinner. By the 1830s, factory-manufactured “fancy chairs”
like those by Sears,
Roebuck, and Co. allowed families to purchase machined sets. With the Industrial Revolution, chairs became much more
available.
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. In the 1930s, stair lifts were
commercially available to help people suffering from Polio and other
diseases to navigate stairs.
The modern movement of the 1960s produced new forms of
chairs: the butterfly chair (originally called the Hardoy
chair), bean bags, and the egg-shaped
pod chair that turns. It also introduced the first mass-produced
plastic chairs such as the Bofinger chair in 1966. Technological advances
led to molded plywood and wood laminate chairs,
as well as chairs made of leather or polymers.
Mechanical technology incorporated into the chair enabled adjustable chairs,
especially for office use. Motors embedded in the chair resulted
in massage chairs.
Materials
Chairs can be made from wood, metal, or other strong
materials, like stone or acrylic. In some cases, multiple materials are used to
construct a chair; for example, the legs and frame may be made from metal and
the seat and back may be made from plastic. Chairs may have hard surfaces of
wood, metal, plastic, or other materials, or some or all of these hard surfaces
may be covered with upholstery or padding. The design may be made of porous materials,
or be drilled with
holes for decoration; a low back or gaps can provide ventilation. The back may extend above
the height of the occupant's head, which can optionally contain a headrest.
Chairs can also be made from more creative materials, such as recycled
materials like cutlery and wooden play bricks, pencils, plumbing tubes,
rope, corrugated cardboard, and PVC pipe.
In rare cases, chairs are made out of unusual materials,
especially as a form of art or experimentation. Raimonds Cirulis, a Latvian
interior designer, created a volcanic hanging chair that is handmade out of
volcanic rock. Peter Brenner, a Dutch-born German designer, has created a chair
made from lollipop sugar – 60 pounds (27 kg) of confectioners' sugar.
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, stacking ability, folding ability, weight, durability,
stain resistance, and artistic design.
Seat height
Ergonomic design distributes the weight of the occupant to
various parts of the body. This is done by having an easily adjustable seat
height. A seat that is higher results in dangling feet and increased
pressure on the underside of the knees ("popliteal
fold"). 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"). Gas springs are
attached to the body of the chair in order to give height adjustment and more
comfort to the user.
Some chairs have foot rests. Around 15% of women and 2% of
men need foot rests, even at the 16-inch (41 cm) chair height. A stool or
other simple chair may have a simple straight or curved bar near the bottom for
the sitter to place their feet on.
Actual chair dimensions are determined by measurements of
the human body or anthropometric measurements. The two most relevant
anthropometric measurement for chair design is the popliteal
height and buttock
popliteal 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 (41 cm) and for
American women it is 15.0 inches (38 cm). 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 (43 cm)
high.
Researchers such as Mary Blade and Galen Cranz found
that sitting on the edge of a high stool with feet on the floor is less harmful
for the lower back than sitting up straight on a conventional chair.
Reclining angle
The type of chair popular in western Hubei, China: with a
fairly low seat and the back inclined at about 45 degrees from the vertical
Different types of chairs can have a variety of seating
positions, depending on the intended task. Typically, chairs intended for
people completing work or dining can only recline very slightly (otherwise the
occupant is too far away from the desk or table). Dental
chairs are necessarily reclined. Research has shown that the best
seated posture is a reclined posture of 100°–110°. In order to recline,
the back-rest may be independently adjustable. A reclining seat and back will
reduce the load on the occupant's back muscles. 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.
Back and head support
The back of the chair will support some of the weight of the
occupant, reducing the weight on other parts of the body. Some back-rests
support only the lumbar region, while shoulder height back-rests support
the entire back and shoulders. Headrests support
the head as well and are important in vehicles for preventing "whiplash" neck injuries in rear-end
collisions where the head is jerked back suddenly. Reclining chairs typically
have at least shoulder-height back-rests to shift weight to the shoulders.
Padding
There may be cases where padding is not desirable, such as
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, weight is distributed and maximum pressure is
reduced.
Armrests
A chair may or may not have armrests; chairs with armrests
are termed "armchairs". In French,
a distinction is made between fauteuil and chaise,
the terms for chairs with and without armrests, respectively. In Germany, an
armchair was once called a Krankensessel,
or sick-chair, because it was intended for people who were too ill to stand or
sit without extra support.
If present, armrests will support part of the body weight
through the arms if the arms are resting on the armrests. Elbow rest
height is used to determine the height of the armrests. 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.
Armrests further have the function of making entry and exit from the chair
easier (but from the side it becomes more difficult).
Seat size and legroom
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 (38–43 cm) deep.
Additional anthropometric measurements may be relevant to
designing a chair. Hip breadth is used for chair width and armrest width. 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.
Types of
chairs
A wide variety of chairs have emerged throughout the ages,
some based on formal usages, and others based on domestic needs, and some based
on needs within the workplace or various professions.
Office chair
An office chair is one used by employees within an
office. Modern office chairs are usually adjustable and wheeled. Caster wheels are
attached to the feet of chairs to give more mobility.
Dining room chair
A dining room chair is a specific type of design, used
around a dining room table. It can be found in most ordinary residential homes,
and also may appear in formal settings, such as any formal event or reception
that includes a formal meal or banquet.
Work chair
A work chair is a specialized chair, adapted to the needs of
a particular profession or setting. For example, a designing chair will be used
for designers who sit at high easels; it will usually have added height.
Rocking chair
Some chairs have two curved bands of wood (also known as
rockers) attached to the bottom of the legs. They are called rocking
chairs.
Kneeling chair
A kneeling chair 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 cushions.
Padding can be on the seat of the chair only, on the seat and back, or also on
any arm rests 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, and thus reducing the
amount of pressure at any given point. By contrast, a hard wood chair feels
hard because the contact point between the occupant and the chair is small. In
lieu of padding, flexible materials, such as wicker, may be used instead with
similar effects of distributing the weight.
Polypropylene (molded plastic) seats and stainless steel
legs in Rio de Janeiro, Brazil. This type of material is very useful in seaside
areas.
Seats
Chair seats vary widely in construction and may or may not
match construction of the chair's back (back-rest).
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
- 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,
- Rush,
wrapped from rush, heavy paper, strong grasses, or hand twisted
while wrapped with cattails to form the seat, usually in a pattern of
four trapezoids meeting in the center, and on rare occasions, in
elaborate patterns
- Reed,
- Rawhide
- Splint, ash, oak or hickory 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, "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 standard ASTM F1912-98. 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) defines
ANSI/BIFMA X5.1 (titled: General-Purpose Office Chairs – Tests) for testing of
commercial-grade chairs. It requires:
- 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 (51 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. Governments will often issue standards for purchases by
government agencies (e.g. Canada's Canadian General Standards Board CAN/CGSB
44.15M 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. An ottoman is a short stool
that is intended to be used as a footrest but can sometimes be used as a stool.
If matched to a glider chair, 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 the 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 back-rests provide support for
the back. 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 different
types of flooring. They are usually made from plastic. This allows chairs on
wheels to roll easily over the carpet and 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 for home
cinemas. They are counter-weighted so as to not slide off the arms under
the weight of the remote controls.
Chair glides are attached to the feet of chairs
to prevent them from scratching or snagging on the floor.
An antimacassar is a cloth covering for a
headrest to protect the fabric and enable easy washing.
Chair sculpture by Steve Mann, exhibited at San Francisco Art
Institute, 2001, comprises spikes that retract when a credit card is inserted
to download a seating license.
As
sculptural and art forms
The Broken Chair is a monumental sculpture in wood, constructed
of 5.5 tons of wood, 12 metres (39 ft) high standing across the street
from the Palace of Nations in Geneva. It has
broken leg symbolizing opposition to land mines and cluster
bombs. In 2001, Steve Mann 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. The
first sitting session was free, with a database of persons who had already used
their free session.
In a performance piece at the 2012 Republican National Convention, Clint
Eastwood addressed an empty chair, as if it represented
President Barack Obama (meant to be construed as MIA or
ineffectual). The address was controversial, with critics describing it as
bizarre and supporters describing it as poignant. Japanese designer Tokujin
Yoshioka has created several chairs as art forms such as
"Honey-pop": honey-comb paper chair (2001), "Pane chair":
natural fiber chair (2006), "Venus": natural crystal chair (2007).
New York industrial
designer Ian Stell creates steel and wood kinetic
sculptures that transform into chairs, including Roll Bottom
Chair (2016) that turns into a secretariat desk
and Loop that transforms into two interlocking chairs when expanded (2015).
Prifardd (Poet) Robin
Owain in the bardic chair, 1991
In Welsh culture, an eisteddfod is
a festival with several ranked competitions, including in poetry and music. The
term eisteddfod, which is formed from two Welsh morphemes: eistedd, meaning 'sit',
and fod, meaning
'be', means, according to Hywel Teifi Edwards,
"sitting-together." Edwards further defines the earliest form of the
eisteddfod as a competitive meeting between bards and minstrels, in which the
winner was chosen by a noble or royal patron.]
In
language
- If
someone "nearly fell off their chair" after being informed about
something, it was because they were very shocked or surprised.
- An orchestra awards
the best player in a particular section a "chair" or "principal
seat" based on ability. The first chair of the section plays the
solos, and in string sections, determines the bowings. In professional
orchestras, the first chair player receives higher pay. 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 in
the US or leader in the UK.
- In
academia, an endowed chair is a prestigious appointment
for a professor, paid for by a dedicated funding source.
- A
chair is the highest officer of an organized group, such as the chair of the board, the head of the Board of Directors in a company or
non-profit organization.
- "Musical
chairs" is a common party
game, and a colloquial expression to describe people shuffling from
seat to seat, around different locations, or from one job title to
another.
- In
American slang, to say someone will "get the chair" is to say
that they will be executed by an electric
chair. Alternatively, it can be a metaphor for
other harsh punishment.
See also
- List
of chairs for an extended list types, such as the lift
chair, papasan chair, swivel
chair.
- Chair
pose
- Chair
squat
- Riding-like sitting
- Seating assignment
- Splat (furniture), the central vertical
element of a wooden chair back
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