Product Design History and Research
The Chair:
A Study in Ergonomic
Design and their
Application within
Society:
Design for
Development in the
Home office
Ayodeji A. Akintilo
Visual Artist
University of Maryland, Baltimore County
Spring 2001
Outline
I. List of Figures
II. Abstract
III. Introduction
IV. Babylonian Era
V. Greco-Roman Era
VI. Byzantine Period
VII. Gothic Period
VIII. The Middle Ages
IX. Renaissance to 20th Century
X. 20th Century to Present Day
XI. Conclusion
XII. References
I List of Figures
Figure 1:Early example sitting posture
Table 1.
Anthropometric Table
Figure 2. The figure in the chair is of a royal status.
Sitting in a reclined posture.
Figure 3. Early Egyptian chairs with lower back support.
Figure 4. Fourth Dynasty Egyptian chair for Queen Hetepheres
Figure 5. Structural detailed
drawing for Queen Hetepheres’ chair
Figure 6. Chair of Darius, King of
Persia
Figure 7. This style of chair had no
apparent design link to the Egyptian
Figure 8. Depiction
of the carefully planned Palace of Minos
Figure 9. The Throne room decorated
with the "Griffin" fresco
Figure 10. The chairs’ backrest develops a slight curvature in Greece.
Figure 11. ‘Diphros’ a rectangular seat with four perpendicular legs
Figure 12. Modern chair design by Mies
van der Rohe for the World Fair in 1925
Fig 13. This graph mapping the
seated Buddha
Fig 14. The meditation position is
usually assumed with the back against the wall
Figure 15. Benches became a part of
Greek culture
Figure 16. Thrones became quite
distinctive and in Rome, the chair was a 'seat of power'
Figure 17. The Byzantine modeled
chairs upon the chest
Figure 18. The handling of manuscripts and volumes
pushed the development of supported sitting in a new direction.
Figure 19. Early manuscripts depicted their ruler, King
David.
Figure 20. Sixteenth century X-chair used by Queen Mary at
her wedding to Phillip of Spain
Figure 21. There was a steady increase
in the amount and diversity of chair design
Figure 22. Chairs appeared frequently
in the home.
Figure 23. The evolution of the chair
remained in the hands of the monastic and scholars of the period
Figure 24. Some clever designs can be seen from this
period. The idea of a 'water wheel'
Figure 25.The seat depth increased to
allow a 'comfortable' seat.
Figure 26. Patent designers,
inventors, and general gadget makers
Figure 27. Backaches from sitting
were recognized and accepted as a challenge by the patent designers
Figure 28. “The measure of
man and woman” written by Henry Dreyfus
Figure 29. Projects by Dreyfus include
tractors and bowling alley seating
Figure 30. Dreyfus and Associations
decided to deal with ergonomic concerns in the workplace
Figure 31. The office
chair was capable of sloping forwards,
Figure 32. Humanscale, a 20th
century design studio, manufactures and designs provide alternate choices in
chair designs
Figure 33. The fact of the matter is
that any position one adopts while at work or at leisure
Figure 34. Henry Dreyfus developed
these chairs that work much like those in hospitals
Figure 35. Four out of five workers suffers from back pain
Figure 36. Even the Buddha recognizes
the need for varied postures.
Abstract:
The Comfort Zone
Ergonomic design as a stimulus for
future development in the home office
The object for this study is the chair. The chair is the most vital machine in the life of the everyday individual. Day after day it is used in both home and office environments. However, its role today has been constrained. It is designed as a place to situate oneself, not for comfort, but take the strain off one’s legs and back. Specifically, most mass-produced chairs have a minimal concern for ergonomics. In 1873 Dr. Christopher Dresser wrote, “ A chair is a stool with a back-rest, and a stool is a board elevated from the ground by supports.” Dresser’s definition shows that focus concerns applied to chair design were dissected into a stool, backrest, and need for elevation. These three concerns form the primary limbs of the chair. Changes in these three elements can result in a pleasing or unpleasing effect, depending on the chairs intended function. For example, chairs can be designed so that workers are stimulated into staying awake and alert or a chair can be designed with an alternate stimulus. The Lay-Z-Boy was designed to promote pure relaxation. It combined the form of a couch and a chair for an individual.
Jeff Running, a journal staff reporter wrote an awareness report titled “A revolution in chair, work station design”. In it he commented on the contemporary work structure. It has created an unfriendly atmosphere, designed to promote physical awareness and mental depression. Industries seek designs that are affordable and transportable, with less and less concerns with improving ones’ posture. A well-attained posture is the key to uniting body and mind.
We are thwarted by electrical impulses between body and mind. These impulses appear as pain or pleasure, and the varying degrees between, governing our actions and enslaving us in a hostile environment. Biologists experiment with exposed areas of the brain by stimulating them with electrodes. The resulting effect causes a contraction of skeletal muscles through direct stimulation of the motor cortex. From this cortex the motor neurons can activate all of our muscles. This discovery has been made evident to millions of viewers in blockbuster films such as ‘The Matrix’ and ‘Fight Club’.
Due to the many economical and
social changes that have arisen the workforce is now moving out of the office,
and into a home office setting. Less factory jobs are available because of
cheaper overseas labor. Computers and machinery have decreased the manpower
needed while increasing the efficiency of production. Mankind is steadily
enhancing computers to handle more tasks. We can see the effects already in
some supermarkets and the automated checkout. When computers have the full
capability to complete their tasks quickly, efficiently, but best of all
consistently then human kind will be shut out of nearly all manual labor tasks
A fast growing trend in American business is to use teleworkers who work part- or full-time away from a central office. Business experts Phil Jacobs, President of BellSouth and Glenn Lovelace, President of TManage, Inc anticipate that more than 30 million US workers will be involved in some kind of remote work by the end of 2000. By 2003, they expect to see more than 137 million teleworkers worldwide. This paper will examine the evaluation of the chair in both the office and the home in an attempt to forecast future developments in the “home-office” as more people telecommute.
Introduction
The chair, as a design, has to be seen as set apart from that of other furniture. Through history humans have required something to sit on. The changing spirit of the arts has sculpted the symbolic nature of the chair. The chair has taken the form of a throne or an electric chair, conferring a variety of high and low status upon its user. In addition to its many functional uses, the chair has maintained its primary role in society, to provide a seat, but more specifically, in the home and the office environment. The study of the history of the chair and its symbolic meaning, as well as historical attitudes about home and office environments, can provide a basis for addressing modern issues concerning the chair within these two environmental settings.
Work and play remain two constants in life. An average worker today works sequentially five days a week and has two days off. The same is also true for the billions of students around the world. This is a set practice in most of the developed world. The workweek closely relates to the biblical story theory of creation. On the sixth day God created man and animals and by the seventh day God had finished the work, so rested from all work. God blessed the seventh day and made it holy. Here we see part of the reason why seven days exist in a week instead of any other possible number. Many other alternate explanations for the creation of time exist. However it is the scientific break down of the Earth’s orbit around the sun, which gave us the number 365 1/4 days coupled with the time taken for the sun to move across the sky which give us our day.
We have allowed ourselves to divide time into small enough values to habituate our lifestyle, thereby constructing our own reality. Many companies today continue to follow God’s example, while more religious countries follow the example of their religious practice more severely, leaving Sunday as the day of rest. No other actions are carried out on Sunday unless it is directed towards worship of their deity.
The work environment has become so distasteful that a new term, “telecommuting”, has been created for a habitual way of life, even though working from home is not a completely new way of life. The five-day work routine is a new concept but has become the norm for most of the 20th century.
The design of chairs today focuses on the role of providing adequate bodily support, while ignoring design’s abilities to aid other functional activities as part of the accessibility of objects within the home and office setting. Attitude towards the application of ergonomic study into chair design has declined. The chair is not a picture to be viewed; it is a functioning machine within another machine, the house.
This paper proposes that the human form is the main concern when designing a chair. The chair must be able to support, but also respond to the individual. A chair may only be possible for specific settings and tasks until the home and office merge.
The need for a more integrated chair that can respond to both work and relaxation will become apparent as the work movement of the office setting and into the home.
The change in the work structure will have a continual effect on society. Speculatively, once the worker is content in his own surrounding the desire to venture outside may dwindle. The world can now be accessed from the comfort of one’s habitat. Not only can humans shop, talk and be entertained through audio and visual stimuli, but they can also educate themselves through distant learning. It might seem that a move towards a domesticated society is at hand. A chair to accustom this new approach to life is needed in the continuation of an evolving society.
The Babylonian Era
3100 - 475 BCE
The first chair ever recorded was depicted in ancient.
Figure 1:This early example of sitting posture is important in establishing the
starting point of chair design. Fundamental concerns that arose when designing
the chair begin with the study of Egyptian ergonomic design practices, as they are the
earliest known example we have to go by.
The stool is the most common and perhaps earliest piece of furniture throughout history. Along with the stool the Egyptians developed chairs, worktops and other useful household items. The chair was used to differentiate between class, within the home and society at large. There were chairs made for specific rulers and for them alone, but at a cultural level most Egyptians had chairs within their homes. In Egyptian society, one could only sit in the presence of another if both people were at equal levels. Floor sitting was common in Egypt as well; in fact Egyptians used chairs far less than we do now. Scribes would work while seated on the floor In order to achieve transhuman consciousness, hyper- natural powers developed through spiritual aspiration. Rulers were instructed to sit upright with their heads lifted on the tip of the spine, while keeping their spines erect and self-supported.
Design
theories approached by the Egyptian craftsmen and designers showed concern for
spinal alignment and the body’s weight distribution. Chairs remained high off
the ground, requiring a footstool sit.
Once seated, the footstool was used to support the sitter's feet,
thereby keeping one’s thighs parallel to the floor. The resulting action
released the strain of the body on the legs and transferred it to the ‘sitting’
muscles. When the height of a chair exceeds the lower leg length of the user
there is compression of the nerves and blood vessels at the back of the thigh.
This uncomfortable posture is alleviated by the user-sliding forward on the
seat with the loss of lumbar spine support. The unsupported spine increases the
loading on the intervertebral discs and creates imbalance in the spinal
musculature. Footstools can reduce the muscular activity of the spine by
ensuring that the user is correctly seated against the lumbar support of the
chair. An additional role for a footstool is the provision of a sloped surface,
which permits the user's ankle to adopt a comfortable angle when the legs are
extended. The sitting postures with the
legs hanging down, resembles very closely measurements shown in anthropometric
tables used by modern furniture designers to determine proper skeletomuscular positioning.
The skeletomuscular unit is a working concept of muscle and skeleton producing
motion. The components of an S-M unit are: bones, a joint, and skeletal
muscle(s).
To achieve this posture, Egyptians regularly used footstools as stand alone objects or built one into the base or foot of the chair.
Figure 2. The figure in the chair is of a royal status. He sits in a
semi-reclined posture with one elbow resting on the back support of the chair.
This relaxed posture is still used in society.
Table 1.
Anthropometric Table: This was compiled from the study of human body measurement for use in
anthropological classification and comparison. Designers use this table to
establish dimensions to accommodate the human form.
|
Segment |
Definition |
Segment
Wt/ Total
Body Wt |
Center
of Mass / Segment
length |
Center
of Mass / Segment
length |
Radius
of Gyration / Segment
length |
Radius
of Gyration / Segment
length |
Radius
of Gyration / Segment
length |
|
|
|
|
Proximal |
Distal |
C
of G |
Proximal |
Distal |
|
Wrist/knuckle
II digit 3 |
.006 |
.506 |
.494 |
.297 |
.587 |
.577 |
|
|
Forearm |
elbow/ulnar
styloid |
.016 |
.430 |
.570 |
.303 |
.526 |
.647 |
|
Upper
arm |
G.H
jt/elbow |
.028 |
.436 |
.564 |
.322 |
.542 |
.645 |
|
F'arm+hand |
Elbow/ulnar
styloid |
.022 |
.682 |
.318 |
.468 |
.827 |
.565 |
|
Upper
limb |
G.H
jt/ ulnar styloid |
.050 |
.530 |
.470 |
.368 |
.645 |
.569 |
|
Foot |
Lat.
mall/hd. MT2 |
.0145 |
.50 |
.50 |
.475 |
.690 |
.690 |
|
Shank |
Fem.cond./med.
mall |
.0465 |
.433 |
.567 |
.302 |
.528 |
.643 |
|
Thigh |
Gr.troch/fem.
cond. |
.100 |
.433 |
.567 |
.323 |
.540 |
.653 |
|
Foot+shank |
fem.
cond./med. mall. |
.061 |
.606 |
.394 |
.416 |
.735 |
.572 |
|
Lower
Limb |
Gr.troch/med.
mall. |
.161 |
.447 |
.553 |
.326 |
.560 |
.650 |
|
Head,
neck, trunk |
Gr
troch/G.H joint |
.578 |
.66 |
.34 |
.503 |
.830 |
.607 |
|
Head,
neck, arms, trunk |
Gr
troch/G.H joint |
.678 |
.626 |
.374 |
.496 |
.798 |
.621 |
|
Head
and neck |
[C7-T1
and 1st rib]/ear canal |
.081 |
1.000* |
.000* |
0.495 |
1.116 |
- |
"Proximal" means closest to the center of the trunk [or
closest to the heart in some cases]
Data are from Winter DA (1979) Biomechanics of human movement, p.
151 - Now published as Biomechanics and Motor Control of Human Movement
Other chairs came equipped with a low backrest and
were higher than the stool. The addition of a low backrest to the chair is a
development that is only seen in these times. The low backrest supports the
pelvis and sacrum in a fixed orientation, allowing the lumbar spine to move
fore or aft to a point of balance. The fixed orientation restrained the user
into an optimal position for healthy spinal alignment. The natural alignment of our spine follows a fluid curve, starting from the base of the skull, leading
through the spinal column and into the pelvis
Figure 3. Early Egyptian chairs with
lower back support may also be identified as a stool with added low back
support. The backrest was purposely added to support the lower five segments of
the back, namely the lumbar. The higher backed chairs would confine the upper
portion of the back while the lower backrests allowed a full 60-degree rotation
at the pivot above the pelvis.
Figure 4. Fourth Dynasty Egyptian
chair for Queen Hetepheres.
This chairs’ large seat area created the space for the sitting postures
to include a folded leg position. The footstool still accompanied some of these
chairs; however, the inclusion of multiple sitting postures suggests that the
Egyptians adopted various sitting positions within one design.
Figure 5. Structural detailed drawing for Queen Hetepheres’ chair
The Egyptians were highly advanced in science and math. This blueprint
demonstrates their abilities to apply anthropometrical data to structural
design. However, no mention of a standard sized or custom-designed chairs were
found, leaving the author to believe that high-ranking officials may have set
the standard size.
Ancient Mesopotamia (3100 – 2370 BCE)
The Mesopotamian Empire developed at the same time as the Egyptians. There was interaction between the two societies; this is documented by the similarity of some of the excavated furniture. It is known that stools, and some chairs, were in use around 3100-2370 BCE, as evident in the remains of pottery and seals excavated in 1968 when the University of Michigan project excavated the early town site of Tappeh Farukhabad. However beyond their archaeological findings there is little record of this period.
It is believed that the Mesopotamians lived at ground level, upon mats and rugs with little more than cushions to give support. Mesopotamian art share Kings, nobility, and religious figures that were exceptions to this. The Mesopotamians and the Egyptians developed similar awareness of posture.
Figure 6.
Darius I, 550 - 486 BC King of Persia,
illustrated
the correct posture for attainment of spiritual desire, which may have led to
his successful reign. He governed his empire wisely, and, for the most part,
peacefully.
The chair with the sloping back does not appear in Mesopotamia, even though it was apparent trade and cultural interaction occurred between the two regions. From the records remaining from this period it seems the high backed chair, often used as a footstool, remained as furniture of royalty and of privileged class.
Egyptian chairs were made with sloping backrest curved to fit the body. The Mesopotamians knew such chairs, but they are missing from the furniture portrayals of this period. Instead Mesopotamian art shows tall straight chairs on which the occupants sat bolt upright.
The Aegean region was a cultural
center for the development and refinement of supported sitting. Few records
remain of this period to indicate the types of furniture used. The exception is
this miniature sculpture of a seated harp player
Figure 7. This style of chair had no
apparent design link to the Egyptian or Mesopotamian furniture of the
time. The stool resembles a folding
stool or x chair found later in Greece and Rome.
In Greek and Roman cultures
the stool was reserved for high-ranking officials. The stool gave the use full
access to the range of postural angles. The author proposes that the stool was
not used for extended periods of time; rather it was a tool to be used for
various tasks.
Minoan Civilization (2000 – 1000 BCE)
The
Minoan’s furniture history comes to us from the excavated ruins of the ‘Palace
of Minos’ at Knossos. This period of
development is known as the first civilization of the European world. The
Minoans had elements of an advanced urban life and a well develop city, with
the Palace of Knossos at its center.
Figure 8. Depiction
of the carefully planned Palace of Minos
Unfortunately Knossos was destroyed and most of the relics from their civilization disappeared with it. The throne of Knossos, constructed of stone, is one of the few remaining examples of furniture form this period. Representations of stools are also found, similar to those used by Egyptians of the time.
Figure 9. The Throne room decorated
with the "Griffin" fresco
The Minoan chair is straight backed. Stools, set flush against the walls, also provide an upright sitting posture. The inclusion of a singular chair suggests that it was a seat reserved for high standing officials.
Mycenae (1600 – 1200 BCE)
Like the Egyptians and Mesopotamians, the Minoans used benches, stools, high seats requiring the use of a footstool, and chairs with adjustable backrests to accommodate varying angles of recline.
The Mycenaean civilization ended
abruptly around 1200 BC. The next five hundred years remain as a void, as far
as the archaeological record of furniture is concerned.
Greco
-Roman
Ancient
Greece (750 BCE – 370 CE)
This is a period of sophistication as represented by the paintings and sculpture of the time. Banquet couches for sleeping or dining were common. The Greeks ate in a reclining pose. It was common for men to ‘lounge’ together, each with his couch, eating from low tables that supported their food. Later women were allowed to recline with men for the purpose of relaxed eating.
Figure 10. The chairs’ backrest develops a slight curvature
in Greece. The design seems to be more for aesthetic reasons rather than
ergonomic improvement.
The chair acquires a broad horizontal back slat at the top that encircled the shoulders of the seated person. This innovation established a fixed form in the classic chair. The backs of some chairs sweep around the sitter in an exaggerated curve while others are straighter, requiring an upright posture.
See Fig 10 and 11
Greek
chair design appears to be of original origin, based upon the Egyptian and
Greek thrones. Typically the legs were
curved, with a back composed of three uprights fitted into a curved board at
shoulder level. Light in weight, the
chairs could be moved about as needed, providing flexibility in arrangement. They offered a new type of support for the
back than the straight back or slanted back chairs of earlier times
Figure 11. ‘Diphros’ defined as a rectangular seat with four perpendicular legs
The backrest sweeps across the thoracic spine and supports the back of the shoulders, forming a cradle-like shell, which encapsulates the user. From an aesthetic perspective the chair became composed of spaces and flowing lines. These chairs were to later form the basis of the design from the 18th – 20th Century. Greek and Roman civilization led the expanse of art and design for an extended period. Civilizations stemming out of the fall of Rome and Greece looked back upon these societies for inspiration. Rome and Greece set the standards for civilized European society.
Chairs,
stools, couch, and tables from this time have remained an inspiration to
furniture designers. For example, Mies van der Rohe designed the Barcelona
chair in 1929 that addressed formal purpose and informality of posture. The Barcelona chair is a cult object. Its
base is the scissor form and carries the concept of a throne, although it is
light and allows a spatial flow. These
chairs were to be used
as thrones by the King and Queen of
Spain for their official visit to the exposition.
The Barcelona
chair became popular as a result of the ingenuity and financial backing
of Mies van der Rohe’s student, Florence Knoll. Knoll reinterpreted the famous
chair and founded a company, Knoll International, which manufactured the chair
and other classic modern furniture designs and sold them to large corporations
in the United States. 
Figure 12 The Barcelona Chair and ottoman, deigned
by Mies van der Rohe in time for the 1929 World Fair.
Examples of Greek furniture from this time are found throughout Asia Minor, Italy, southern Russia, North Africa, and in the East, where the stool exerted a great influence.
In their designs, the Greeks expanded upon concepts of the couch, the chair, and even the stool. Even the word "chair" comes from the Greek language, a contraction of cathedra—in turn a compound of kata, meaning "down," and hedra, from "to sit." A chair is a piece of furniture with a back, and usually four legs, on which one person sits. But so is a throne. However, the word "throne" has a different origin. It comes from the Indo-European base dher, meaning "to hold or support." The throne supports, while the chair is a place to sit down. A throne suggests the palanquins on which a potentate might be carried, while the underlying meaning of a chair is quite different. Physically, almost anyone can sit down, whereas only a very privileged few can be carried. Thus, a chair is more common and ordinary than a throne. From the beginning of recorded history, two types of chairs developed: the upright throne, and the more relaxed clismos, a chair with a modestly inclined back. Today, we mock the lowliest chair of all, the toilet, by giving it the term of greater privilege, "the throne."
The sweeping curve shown in Figure 10 does not conform to the natural sweeping curves of our spinal column. The shape of the curve may have been approximated for style more than comfort. The relaxed posture is one that we use today and may have used since the dawn of man. Contemporary scholars view the clismos posterity as superior to that of the pharaohs, but I think the reclining posture is one that should be assigned for recreation and not serious contemplation. The erect posture properly aligns the spine and skull, which closely resembles a standing posture. Once the body is perfectly aligned the flow of energy through our very being would be significantly accelerated.
The stool developed in two forms, one termed ‘diphros’, often had four perpendicular legs and a rectangular seat, often with a rug for padding. The other became known as ‘diphros okladias’ in which the legs cross, as in the modern stool. These were rather elaborate in design and could fold to allow easy transport when traveling. The same type of stool was first depicted in Aegean culture.
Figure 15. Benches became a part of Greek culture, used in
schools and theatres by philosophers and their audiences’. They also accustomed
Greeks to sitting on the ground. The 'speaker' would sit in an almost
throne-like chair, setting him/her apart from the audience much like the throne
room at Knossos.
Footstools were in use whenever
people sat in higher chairs. They were also used as a stepping-stone to mount
high couches The Greeks would eat in a reclining pose, food lay on table next
to the couch. Once finished with, the table would be pushed under the couch.
The notion of 'comfort' is said to have derived from the Greeks. Certainly the Greeks appear to have enjoyed their leisure time, adapting the chair for more comfortable support and developing furniture to suit their bodies in recline. It is with the Greeks, that the notion of supporting the body while undertaking alternate postures develops.
Rome
(2000 BCE –315 CE)
The Romans did not expand upon the furniture of the Greeks. Rather, they kept the designs and added to the adornment and decoration. General styles similar to those of the Greeks were found distributed throughout the Roman Empire.
Figure 16. Thrones became quite
distinctive and in Rome, the chair was a 'seat of power'. Chairs were widely
used by the Romans and more so field commanders of Roman armies.
Roman chairs lacked a structural concern for comfort, and were heavily decorated, but the Romans maintained two types of chair: the thronus and cathedra. The thronus, used by members of the government, religious factions and scholars, had an upright back. The cathedra, used mostly by women, had a sloping back. In the home the father would eat reclined in a couch, while the mother would sit nearby on a chair, and the children sat on stools.
Romans were a militaristic race beset upon conquering other lands to fill their desires of a great empire. Eventually the Roman Empire conquered most of, if not all previously established empires. Therefore it is understood that many of their design interventions stem from these other societies, which they governed. The tradition of their society was to enter foreign lands under the pretense of friendly trade. Once a trade agreement was established troops were sent to siege the cities and overthrow the local government.
The collapse of the Roman Empire signaled an end to the furniture seen in these times. The legacy of antiquity was abandoned and with it, the subtle curving shapes, the rounded backs and the sweeping saber legs seen in Greek and late Roman furniture, vanished. It is not until the Seventeenth and Eighteenth Centuries that designs resembling the Greek and Roman styles reappeared.
Post-Roman Era: Byzantine Period (330-1653CE)
In the fifth century AD, the mighty Roman Empire fell to invading barbarians and complex internal pressures. The land that had been centrally governed for centuries disintegrated into numerous warring states. The Empire of Byzantium was the eastern portion of the Roman Empire, divided in 395 CE.
The
traditions of the classical arts were however not completely lost. The
Christians took over the 'classical figures' and adopted them to their own
uses. The chair now takes on an architectural form, usually massive in
construction and with a straight back.
Figure 17. The Byzantine modeled
chairs upon the chest, which were steadily becoming the substitute for the
stool. It combined two functions into one design by allowing for storage space.
The cubical void that resided underneath the chair was drastically reduced.
The chair was severe in its form and was only used by figures of power, authority, and for ceremonial purposes. Comfortable support was not a consideration. The notion of 'ascetic' was gaining favor in the monastic societies that were developing with new furniture emerging to meet their needs.
Figure 18. The handling of manuscripts and volumes of text pushed the development
of supported sitting in a new direction. Repetitive tasks raised demands for a
higher level of ergonomic design as it now applied towards the work
environment. The high chair forces the head forward and in doing so out of
alignment. Tension collects at the base of the pelvis as a result of this
posture. Reading must have been very difficult to do in chairs such as these.
Either one would develop back pains from leaning over, coupled with
long-sightedness from reading to close to the material. The other outcome is
the development of shortsightedness from attempting to read from far away.
This is the first example of the work environment effecting the design specifications of chairs. It is also significant as it occurs at the dawn of the middle age of human society.
The Middle Ages (700-1700 CE)
Figure 19. In early manuscripts of the tenth century,
the rulers, i.e. King David, are often portrayed sitting upon fold-stools.
The rich adorned the fold stool, with decorations. And in later years, as higher forms of furniture came into use, the fold stool remained the most decorated. Another descendant to the fold stool the Faudesteuil, an armless folding stool was designed in the 16th century. Catherine de Medici inventory lists an armless fold chair with a reclining back.
Figure 20. Sixteenth century X-chair used by Queen Mary at her wedding to Phillip of Spain. The x-chair was neither collapsible nor lightweight. It tended to be reserved for royalty.
By the end of the century, the design of the chair was becoming a matter of stylistic change. There were many obstacles, in the way of its realization, and chair design continued to react to social changes. The steady increase in the amount and diversity of chair design changed the way of life. Modes of social intercourse among the upper class began to affect the chair’s very nature.
Figure 21. The chair was vernacular in
many areas throughout society, so much so that a small revolt against the
liberation of chairs led into the workplace and home. The revolt was made
through drawings like the example shown here people saw chairs as objects,
which added more clutter to the world.
Figure 22. Chairs appeared frequently in the home.
People would have guests over on regular instances. This social aspect of
Middle age society required large tables and many chairs to accommodate guests.
A level of hierarchy was maintained and the host would sit in a chair with
backrest while the guests sat on stools or benches.
The Gothic Era (1280-1515 CE)
The early Gothic period was a time without the chair for the general population. The three-legged stool remained a part of everyday life; sitting was a very informal affair. People were accustomed to seating in very close proximity to each other, often crowding together. Cushions were used on the floors as added comfort. Stairs and steps leading up to the high-posted beds were also used as sitting areas.
The
chest developed as the universal furniture of the Middle Ages. It was portable,
used for storage, and providing seats. A characteristic part of medieval life
was transience of abode. Living situations were often temporary even with the
nobility and kings, who traveled with all their belongings usually in great
chests. Folding stools remained a useful addition to the traveler’s lot.
Figure 23. The evolution of the chair remained in the hands of the monastic and
scholars of the period.
While the common man made use of upturned buckets, stools, and crude wooden benches; the monastic communities were developing the chair for utilitarian functions, i.e. record keeping, writing and painting. It was the church that developed sloping tables, lecterns, and tables capable of angular adjustments to hold their books and papers at eye level. This fairly simple addition single handedly improved sitting conditions while attaining comfortable viewing distance and angle.
It was not until the Eighteenth Century that horizontal tables became the principal type for these particular activities, a period associated with the development of libraries. In later centuries the sloped desk was the standard desk used by draftsmen and architects alike.
Figure 24. Some clever designs
can be seen from this period. The idea of a 'water wheel' arrangement also
appeared in the form of a document holder
The Renaissance (1450-1600
CE)
In the arts and sciences as well as society and government, Italy was the major catalyst for progression during the Renaissance. “Renaissance” is a word with many layers of meaning because of the number of different fields in which it is applied. Accordingly, Renaissance chair designs cannot signify any one common or clearly definable style. As Gothic paintings had been shaped by the feudal societies of the Middle Ages, with its roots in the Romanesque and Byzantine traditions, Renaissance art was born out of a new, rapidly evolving civilization. It marked the point of departure from the medieval to the modern world and, as such, laid the foundations for modern Western values and society. The Renaissance was a time of rebirth and massive cultural upheaval. Artists of all kinds in Western Europe became more aware of the classical past and the world beyond the narrow confines of medieval theology.
The Periods known as the Renaissance, Baroque
Classical and Romantic, showed only moderate changes in art and design. They
can be best described as the “Cabinet Maker Era” and the “Upholsterer Era”. The
changes in design methods during these periods were mainly to benefit the rich
and bourgeois society. The workforce at the time did not hold positions,
requiring them to sit for long periods of time.
Baroque Period (1600 – 1750
CE)
By the mid-Sixteenth Century, the chair was a common piece of furniture throughout Europe. Made for the wealthier and noble members of society, the chair's design continues to become more diversified to meet the fashion desires of the privileged classes. Chair design began to move away from the heavy, and harsh angular shapes, and towards a lighter design. This period returned to frame construction similar to that of the Greek chair, incorporating flowing curves and a backrest to support the sitter. It was the return of the forgotten standard of creating a support for the body that allowed highly relaxed posture. Posture and the chair were again seen as one.
Classical Period (1750-1820 CE): “The Upholsterer Period”
With the advent of new technologies, methods, and materials, the upholsterer emerged as the new chair designer. Chairs and stools previously used cushions and limited upholstery, but only in a minor way to augment the woodworker.
Figure 2? Hepplewhite sofa
Damask fabrics and woven rattan were widely used and many types of designs emerged from the textile mills, leaving upholsters’ to find new imaginative uses for them, including the ornamentation of the chairs. There were eleven design interventions in America alone within the 19th century. To name a few: Pennsylvania Dutch, a simple, utilitarian American country style of furniture with Germanic influences. Shaker, a simple and utilitarian style produced by the religious group. The Sheraton, named for English designer Thomas Sheraton who published his designs in "The Cabinet Makers and Upholsterers Drawing Book" in 1791. It is a neoclassical style characterized by delicate straight lines, light construction, contrasting veneers and neoclassical motifs and ornamentation.
The upholsterers used the 'skeleton' of the wooden chair and transformed it into a completely new form by softly padding the edges, the addition of voluminous cushions and plush materials. Cushioned padding provided support, while backrests rise up to encapsulate the sitter. Instead of giving us more freedom it forced a static surrounding, which would not alter according to our movements.
Figure 25.The seat depth increases to allow a 'comfortable' sitting position and padded armrests invite a flailed leg or weary elbow. The chair, with some of the chairs actually being called ‘uncomfortables’, invited slumped, passive postures.
The Patent
Era (1793-1836 CE)
The chair became diversified in its form to meet
each newly identified function, with support for the human body as high
priority. The notion of passively positioning people in chairs became well
cemented in designs from this point forward. However different notions of
postured positioning emerged. Relaxation and comfort, as demanded by the new
middle class, became the 'Holy Grail' for these chair designers.
Figure 2?. Arts and Crafts Morris
chair, with a Wing back design and a reclining back. The unique
feature of this chair is the armrests that open for storage of your pipe, your
remote controls, or just your snacking stash.
Designers such as William Morris, the founder of the Arts and Crafts movement, were interested in the problem of motion while supporting the body. The notion of adjustability and flexibility of design was paramount, as the engineers dissected the chair into its planes, making each plane capable of regulated movement.
Figure 26. Patent designers,
inventors, and general gadget makers turned their energies to chair design,
e.g. Ringling Brother chair.
Figure 27. Backaches from sitting were recognized and accepted as a challenge by the patent designers, and as a result the rocking chair was developed. This form was then merged with the revolving chair. Springs were attached to the adjustable backrest, allowing the sitter to move interiorly ( about the axis of the spine and pelvis) with continued support, theoretically.
Patent designers left few stones unturned in their quest for relaxing and comfortable designs. Dentist’s and Barber’s (previously the same professional group) chairs became fully adjustable in every direction in order to position the patron in the most convenient position for themselves. Railway seats for the new trains of the time could lie out flat, cantilevering above and below each other to allow the passengers a comfortable nights sleep.
The American Patent Office in the 1870's had 70 sub-divisional categories for chairs of different purposes. Some of the designs were awkward, while others took account of ergonomics.
20th Century to
Present day: The Modern Era
The beginning of the Twentieth Century was a time of revolt against the patent furniture movement. Furniture was becoming an integral part of the house and office setting, with function assuming lesser importance to form. Aesthetic design became the guiding force, with the chair place within it, and its interaction with the space of the room considered. New materials were used, in the form of steel tube, wire and later plywood. These new industrial materials provided designers with new scope for their designs and aesthetic notions, and as a consequence the way people sat was to alter again.
Figure 28. “The measure of man” written by
Henry Dreyfus, details his study of the human form and how it is positioned. He
also developed “Humanscale” which covers many of the same design concerns but
comes with a scale of proportions for designers to use.
The
'office' chair becomes a common part of the industrial age, while other
specialized in chairs to fill market niches. It was not until the 1890's, some
twenty years after the introduction of the typewriter when the typist chair,
received attention in its design. Industrial designer Henry Dreyfus was of the first
in his field to conduct research experiments for a better office chair.
Figure 30. Dreyfus and Associations decided to deal with ergonomic concerns in the workplace through a series of tests using test subjects and a seating machine
Dreyfus
has performed extensive testing of the human body in order to gauge the
specifications in structural designs, in the chair but in other consumer
products such as telephones and weight training equipment.
The reliance on the automobile due to long distance job commutes
driving became a significant part of our daily routine. We spend large amounts
of time in cars. So much so that driving can now be considered a major source
of physical and psychological stress in day-to-day living. Recent figures from “Effects of
Driving.” by Paul L, reported 180 million drivers in
the United States. Men drive an average of 44 miles and women drive an average
of 34 miles per day. The
challenge for the manufacturer was to strike a balance between safety and
comfort by examining potential sources of stress facing the modern driver. The
prime ergonomic elements became posture. Where force and repetition are it is
posture that is most important to the driver. Any deficiencies in postural
design of the car seat contributed to tension and fatigue on the part of the
driver and subsequently detracted from their performance.
Figure 2?. The Skycar. Invented by Moller International.
Experimental computerized self-driven transport vehicles have been developed in Europe that are designed to travel caravan style and without the need for human occupants. Technology continued further into automating the work environment and its results can be seen in the "Skycar", a car with vertical take-off and landing capabilities. The vehicle is a Jetson-like flying machine that actually resembles the Batmobile. The inventor believes that his vehicle may be mass-produced in the future for about $60-80,000. The vehicle utilizes a series of efficient rotary engines and cruises at about 350 miles per hour. It is presently in the testing stages and when available to the public could radically change the structure of our society
Figure 29. Projects by Dreyfus include tractors and bowling alley seating and ball returns at AMF bowling alleys.
Figure 31. The office
chair was capable of sloping forwards, as was common in 'sewing machine'
chairs. The backrest was spring loaded to provide support to the typists’
shoulders as they moved positions. The guiding principles in the design were
concerned with postural support and comfort, whether sitting upright, leaning
backwards or reclining.
The twentieth century also marked the dawn of the work schedule and people were placed into intensive office settings. This occurred mainly in the USA but was quick to spread across the globe to Europe and parts of Asia that traded goods and items frequently with the rest of the world. Internet time was standardized by Swatch and the electric light was created. With the glow of artificial light source the importance of the sun dwindled as the bringer of light and darkness. This made it possible for extended hours to be spent at the office. Immediate problems arose, especially among jobs that required repetitive tasks such as typing. Complaints over increased tension in the back and sitting muscles grew steadily. After so many complaints companies were forced to provide better office chairs for their employees. The number of days missed had started to effect the budget, and when research showed that an increase in medical leaves had resulted in a slow down in production the designers were asked to solve the problem.
|
CODE |
DESCRIPTION |
MEASUREMENT (in inches) |
|
a |
seat depth |
16 - 19 |
|
b |
Seat height adjusts. Range |
16 - 211/3 |
|
c |
Base diameter |
26 (diameter) |
|
d |
Backrest width |
21 |
|
e |
Height, standard chair |
331/2 - 411/4 |
|
f |
Seat width |
21 |
|
g |
Back rest height |
5 |
|
h |
Height, advanced chair |
43 - 56 |
|
i |
Stool height |
16 - 211/2 |
Figure 32. Humanscale, a 20th
century design studio, manufactures and designs provide alternate choices in
chair designs, which provide comfort and usability. They even adopted the stool
that they term the ‘freedom stool’, which is a modification of stools found in
Pre-Dynastic Egypt and Aegean society.
In many ancient cultures, many of our modern chairs would have been reserved for the old, the royal, and the leader--the person of greater importance. The seat was a symbol of leisure and relaxation as well as the base from which contemplative thought could occur. In modern times the chair has developed a darker legacy. Sofas, easy chairs, school desks, car seats, office chairs, even plane seats have become instruments of torture for the body. Designers have come to their present place in ergonomics only to find that they have themselves created new problems within their design.
Figure 33. Any position one adopts while at work or at leisure,
if one resides in that position for an extent of time will undoubtedly result
in increased tension in the muscles and deterioration of ligaments. The modern
chair eliminates the opportunity for the hip joints to open, close and rotate
out to the sides. It has focused entirely on providing all around support while
forgetting the necessary requirement of stimulating the user into changing his
posture by exercising his range of actions through a multitude of tasks.
In 1995, Prof. Antonio Grieco, the director of the Institute of Occupational Health, and Dr. Maria Castriotta, both Italian members of TNG research reported the results of their test based on the sitting practices accustomed to telephone operators. Operators from ISPEL, an Italian communication company, were tested in both their old workstations and their new ergonomically designed workplaces with added video display terminals. Results showed that their movements were cut in half. He then concluded his report by stating that ergonomically designed furniture could not resolve all the problems of sitting. This report was published in Italian National Report in 1999.
Today there are many new developments in chair ergonomics as the result of industrial design and the mass communication that helped to spread it. America was the container for this culmination of design philosophies, perhaps because it was the most in need after the drastic increase in its work force, or maybe because America described as the modern day Rome by members of The Department of English Spring 2002 Rome Program, is still trying to assimilate all cultures into its empire. Due to the mixing of Buddhist, Egyptian and Greek philosophies towards sitting, designers were able to solve many issues dealing with comfort.
Figure 34. Henry Dreyfus developed these chairs that work much like those in hospitals, providing a number of different postures to recline.
Chairs were generally out of sight and out of mind, like most hidden environments. Once it's in plain sight we do look at it and when we see a Queen Anne, a Stickleback or a Bauhaus: we collect it, ornament it, position it, and cherish it without seeing the side effects. Chairs still convey status upon their user. Certain members of the family have their own personal chair either for dining, leisure or work. Certain members of the government and of the monarchy have specially designed chairs, very few however have custom tailored chairs that can provide the modern standards of comfort The chair distends our seat, simultaneously numbing the largest muscular system in the body, the one pivotal to all physical action. They deliver us to a technology, which numbs our bodies according to that technology's specifications. E.g. slouching when we watch TV is necessary in attaining a higher level of comfort within the seat. We numb the head because the medium demands. Chairs often promote the head and control, while desensitizing the body. This separates the body and mind instead of helping to unite them. The sitter, bodily numbed, cut off by desks, then boxed in a cubical placed in an office, relies on technological senses for vital information. He no longer accesses his original sensory tools, necessary for direct mimetic observation. His other senses numb, he tends to rely on the eyes as the main source of perception. Once we have numbed one of our sense another rises to takes its place and it is usually more in tuned
Figure 2?. Excerpt from Balanced
sitting posture on forward sloping seat by A.C. Mandal. MD. Copenhagen. J.J.Keegan, an American
Orthopedic surgeon, made in 1953 a series of x-rays of people lying on their
sides which documented the large movements that took place in the lumbar section
of the spinal column as the position changed from standing (a) to right angle sitting (c) and bent-over positions (d). B is the natural resting
position, as when you lie on your side while sleeping. The lumbar curve is
retained and the muscles are relaxed and well balanced.
A sitting posture that approaches the natural resting position (b) is a more suitable position
and allows the spine to carry the body weight in a more comfortable way.
Stand-up desks with their high stools and slanted surfaces began to disappear from banks and offices at the turn of the twentieth century, replaced by the conventional 18-inch chair and its flat desk. All humans would eventually grow to be the same size if required to sit in these chairs. Stackable chairs and tables required a flat desk surface for undemanding storage. The necessity of space saving furniture outweighed the concerns for school children’s’ physical, and in many ways mental, well being, turning them into postural pretzels, with exceptions made for the few designers that offer seating solutions for many aspects of life. Even less of these designers attempt to solve both problems in the same design
The standardization of the chair
resulted in added concerns in ergonomic furniture. Medical analysis provided
designers of today with vital information regarding work practices. Ergonomic
furniture, with proper adjustments does reduce the risk of injury. However the
risk of injury is not entirely eliminated. Work practices can help reduce the
risk even further. This includes proper job design, which along with changes in
job tasks should include frequent changes of posture. It is important to stand
up, move around, stretch and get away from computing tasks during the workday.
Doctors advise that we should listen to our body. No two bodies are exactly the
same. If we feel discomfort in a particular posture then we should move around
experiment with different ways of working. When all of these tactics fail to
achieve the desired effect we are advised to see a health 
professional for advice.
Figure 35. Four out of five workers
suffers from back pain and 20% take time off work because of it. Most of the 1000 people
surveyed worked in environments that required light but frequent lifting, but a
sharp and steady rise in the percentage of disgruntled office employees was
noticeable.
Many of today’s
modern designs specialize in space management and aesthetic qualities. Offices
created the demand for neat stackable items, which can be mass-produced.
A lot of people think that sitting is easier on their backs than
standing or lifting. People whose jobs require them to sit for long periods of
time suffer as much from back pain as people who lift all day long. Huge
increase in back pain over the past couple of decades has a lot to do with the
fact that more and more of us are spending our work days in chairs Now that the
office is changing demands for alternate ergonomic solutions have to adjust
accordingly.
The following
report on the functionality of the work environment was taken from bi-ca.com a modern day workstation
manufacturing company. “The office of
tomorrow today Ergonomic Work Station Design:”
The terminal and keyboard height should all be fully adjustable. When this is the case, the chair should be the first piece of furniture adjusted to fit the operator. Once the chair has been properly adjusted it should be used as a reference point for all further adjustments. The feet should be firmly planted on the floor and the upper body in a neutral position, the monitor and keyboard position should then be adjusted. If the work surface height is not adjustable, the chair should be fitted to the workstation and a footrest provided to support the feet if needed. Specific guidelines for these adjustments are outlined in the following section.
Chair
The chair is the
starting point for designing a comfortable and healthful workspace. The
following features are important:
- Easily adjustable chair height
from with a minimum range from 16 - 25".
- Seat pan large enough to provide
support for thighs and buttocks, but not pressing the back of the knees.
- Seat pan with waterfall edge at
front to avoid pressure on underside of lower thigh
- Easily adjustable seat pan tilt
- Easily adjustable back rest tilt
and height providing lumbar support
- Easily adjustable arm rest height
- Breathable material and a
cushioning that gives way no more than1".
The yoga tradition also offers a solution to the problem of chair design They advise us to use the body itself as a chair or seat. One must arrange the body so that it is self-supporting and efficiently aligned. The Sanskrit word for a seat and for a chair is “asana,” derived from the root verb “as” or “to sit.” We commonly translate “asana” as “posture” or “pose,” but this translation doesn’t carry quite the same implication as “seat.” “Seat” implies a support upon which you can totally release your weight. A seat, such as a throne or an academic “chair” is also symbolic of the powers that support you and that are at your command. The throne in Greece represented similar philosophies and so did the erect posture of self-awareness in Egypt. These can be associated with meditation traditions instituted in China, India and the Middle East. From India arose Buddhism and the Buddha. He is known for his spiritual enlightenment, which he achieves through many postures.
Fig 13. This graph mapping the seated Buddha highlights the points of our bodies that are in alignment. This pose creates a triangular vortex centering on a point just below our ribcage.
The most common is the upright-seated posture.
While at this level of being the pathway to utopia and union with the greater soul, which we are apart, can be attained. Support was sustained in ones back by sitting in the clismos which encased the user in a womb-like encasement; however, the curvature of their chairs is highly exaggerated.
Fig 14. The meditation position is
usually assumed with the back against the wall and heads held slightly forward.
Future designs in chair design must
not provide for all of life’s comforts. The chair must be designed to
accommodate the occupant. It should adjust to his posture, providing a
comfortable reaction to any action placed upon it, but should not force the
user into a set posture. The adjustable chair must mold to the occupants’ body
during a multitude of positions while remaining focused on areas of heightened
stress and without forgetting the basics of structural elements under the force
of gravity. It must make necessary frequent movement while still supporting
ideas of comfort. Comfort is not attained through 
one
position.
Figure 36. The Buddha recognizes the need for varied
postures. Certain postures go together with individual thought processes. The
chair must allow our mental course of action to determine our physical
positioning, not the other way around.
Adding multiple functions to the
workspace would assure a healthy lifestyle. In the case of the developing home
office these functions can be divided into two columns from which to begin
research.
|
Home Tasks |
Office Tasks |
|
Eat/ Cook |
Phone |
|
Sleep |
Fax |
|
Shave |
Scanner |
|
Bodily functions |
Photographic/ Video Equipment |
|
Shopping (groceries/equipment) |
Drawing/ note taking |
|
Exercise |
Greeting and entertaining guests |
|
Socialize |
|
|
Household chores (e.g. waste disposal) |
|
Table 2. Division of home and office requirements is
essential in establishing research criteria needed to improve the human
condition while at work or at leisure.
These are not necessarily routines carried out by
everyone but merely a summary of common routines gathered from a random
questionnaire conducted by the author on a broad sample of 20 students and 20
IT professionals.
The home office for today’s’ society must allow for family and friends. As we are social beings we seek the presence of other. The two may coexist, e.g. working while in the company of others, being in the company of others while thinking about work. The solution lies in the chairs’ ability to achieve both instances. Once we can learn to combine both aspects of life into one state of being we could become more emotionally stable which may lead to an increase in productivity, in both the work place and in social situations.
Conclusion
This study demonstrates the value of design research in the design of a chair. Advancements in technology have allowed the work environment to create a standardized cube from which we are to work with no incentive other than our salaries. The rise in telecommuting due to heavy increases in computer technologies launched the first stages in freeing oneself from the shackles of social responsibility. This movement began in the IT industries but include many design fields; however, many companies are now noticing the benefits of telecommuters. Millions of dollars can be saved on construction and utility costs alone. Once within a favorable environment we will be able to achieve a higher sense of relaxation and contemplation, more so than in a hostile one.
It has been strange to see how the social structure of our environment has been geared towards the work schedule of the everyday person. The general public readily accepts this work ethic even though it has only been in existence for two centuries at best. If social attitudes is truly effected by the social structure, e.g. school systems, workforce, government, and in many case defines the design needs of that time, then this period of commuting to work is soon to end. The result of which may send world economies into a rip curl, as fuel consumption per person decreases the price of fuel may also drop. Even the rise in gas and electricity prices would not account for the sharp decrease in petroleum. The economic instability that this would cause is immeasurable. However when the finite fuel sources on our planet are depleted it will come as less of a shock to the worker if one has already cut down on his traveling distances.
It is important that we
concentrate all our effort into accommodating the next generation of the
working age population, which form the majority of the worlds’ population and
are the backbone to this planets’ economy. An extended lifespan with the added
benefits of good health are the direct results of a proper functioning work
system. It would be more of an anti-progression to continue with this work
ethic as it is today. Employers now realize that if they do not satisfy their
employees with generous compensation, perks and training, there are plenty of
other employers who will.
The changing
environment can be explained by two inescapable trends that have converged to
create the new employment paradigm (NEP): information technology and workforce
demographics. IT has reduced geographic barriers and propelled the global
economy into a period of long-term continuous growth and job creation. In this
way, IT caused the world to have an insatiable appetite for more workers.
However, workforce demographics show that there are very few skilled workers
available The Electronic Recruiting Index of 1999 predicted a modest shortage
of 2.3 million workers in the American economy as of January 1, 2000.
According to Tony Lee,
editor-in-chief of Careers.wsj.com, the guiding principle between employee
retention and a company is "all about relationships". The worker
needs to feel appreciated, invested in, challenged and/or compensated. For the
organization, goals and objectives include profitability, productivity,
efficiency, and quality service. The worker and organization determine the
level of satisfaction against their respective success measurements. Once the
employer allows for telecommute based environment employees would receive more
freedom in their work schedule. In return the employees would feel respected
for the vote of confidence, thereby increasing productivity.
Employment today is a seller's
market. Corporations must adapt their practices in radical steps. Those who do
not adjust will find themselves "human capital poor" and vulnerable
to competitors who acted more proactively.
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