Our Own Devices: How Technology Remakes Humanity

by Edward Tenner

  High-handed and even authoritarian as the system seems now, its appeal to scientific expertise sold chairs. The line was hierarchical, ranging from “factory” to “clerical,” “junior executive,” “executive,” and ultimately “mediator,” a judge’s chair for top executives, later used by Harry Truman in the Oval Office. And the company gathered testimonials. In the New York City garment district, manufacturers reported reductions of back problems and unauthorized breaks. The secretary of State Farm Mutual Insurance Company wrote in 1939 to attribute its over 99 percent employee attendance rate to the company’s 739 Do/More Chairs.37

  Of course, there were other posture-conscious firms. A man named Charles E. Pipp offered a “Pep Chair” in 1921 with adjustments and features resembling the Do/More’s. The Gunlocke Company, which specialized in luxurious suites for top executives, introduced its Washington Series in 1923, and Evan S. Harter produced an Executive Posture Chair in 1927, one of the first chairs with controls for synchronizing back and seat reclining. But Do/More, as a newcomer, was most systematic in relating the technology of its chairs to the proper techniques of sitting. Its health campaign helped prepare for the postwar design renaissance.38

  The metal shortages of World War II interrupted the refinement of office chair mechanisms; Do/More and no doubt other companies were able to continue producing steel executive posture chairs only with medical prescriptions. But indirectly the war had an immense influence. Steel was a mature technology, but defense work had helped industry metallurgists develop improved techniques of tubing, stamping, bending, and welding. And the war forced a new round of attention to human-machine interaction, from aviation seating to the design of controls. Military sponsorship of human factors studies helped create a new cadre of professionals.39

  Introduced in the 1920s and based on English industrial seating, the Do/More Chair was the first to be marketed nationally in the United States for its health and morale benefits. The line was extended upward to include more richly upholstered and imposing executive and managerial models. More recently, the Domore Company produced some of the first chairs especially made for air traffic controllers, emergency service dispatchers, and other intensive users and is still an active supplier. (Courtesy of Lux Steel Inc.)

  During the 1950s and 1960s, work chair design was demedicalized. Do/More continued its system, but it had new competitors with less physiological and more aesthetic goals. After a fifteen-year break in office construction, a building boom began, but the large corporate architectural firms and their clients shunned the shop-floor culture of exposed metal of the 1920s and 1930s in favor of sculptural forms using not just metals but plastics developed during and after the war. Knoll International’s classics swept architects and clients off their feet: Eero Saarinen’s tulip chairs, Charles Pollock’s swivel armchair with its one-piece plastic shell, and above all Charles and Ray Eames’s fiberglass series and their aluminum group became icons of the postwar years. As popular culture, medical thought, and etiquette books alike moved away from the full upright position of the interwar years, seating emphasized ease and flexibility, not support. Posture-enforcing technology was becoming passé. Niels Diffrient, who worked for Saarinen in the early 1950s and knew most of the other star designers, recalls that none of them expressed interest in human factors. In a Knoll company history of the 1980s, Pollock described his executive chair of 1965 as built around its extruded-aluminum rim, observing that it has “no inner spine.… It doesn’t rust, it doesn’t tarnish, it doesn’t fade.” Even Do/More (now Domore) hired the influential designer Raymond Loewy to rejuvenate the lines of its seating, though not to change the mechanism.40

  FROM POSTURE TO ERGONOMICS

  Most of the celebrated 1950s and 1960s chairs departed from the old posture standards. The Pollock armchair lacked a lower-back support, and its shell enforced a rigid angle between back and seat. Gradually a new posture movement emerged, first identified as “human factors” and later as “ergonomics.” In 1967, air traffic controllers sat in rickety tubular-frame swivel chairs and leaned over tables to use horizontally mounted instruments. As part of a reform of their work conditions, the Federal Aviation Administration (FAA) tested dozens of chairs and issued a set of guidelines for controller seating, governing everything from the backrest action to the shape and adjustment of the seat. Domore won the competition to produce a new chair for every air traffic controller. These Domore chairs may have been the first major postwar line available in A, B, and C sizes for a single style. For Domore, the contract opened an important niche, round-the-clock seating. (The FAA still uses 16,000 Domore chairs.) And it also helped turn the attention of architects and their clients back to the health side of seating. By the mid-1970s, the two largest office seating companies had posture chairs of their own: the Steelcase 430 Series (1974), derived from aerospace human factors research, and the Herman Miller Ergon chair, based on time-lapse photographic studies by the designer, William Stumpf, at the University of Wisconsin. With its high back, body-fitting curves, comfortable edges, and ingeniously placed armrests, the original Ergon helped make posture chic again—under the new aegis of ergonomics. It was the first chair to take full advantage of new foams and plastics to create a distinctive shape without compromising comfort or motion.41

  The Aeron chair, the Leap chair, and the Freedom chair offer complementary features. The first (above) is celebrated for its cooling mesh and a deep, rocking recline motion. The second (facing page, top) has a seat pan that slides forward, separate upper- and lower-back controls, and a lumbar support that curves snugly. The third (facing page, bottom) needs minimal user adjustments and provides an especially deep reclining position, and (as options) a synchronized headrest and an ottoman. The shared ideal is no single posture but promotion of healthy variation—especially reclining. (Courtesy of Herman Miller [photographer: Nick Merrick, of Hedrich Blessing], Steelcase, Inc., and Niels Diffrient)

  Stumpf’s ideas on posture reflected a restless, experimental decade. The Tan-Sad and Domore generations had sold efficiency and productivity Stumpf doubted openly that the ergonomic design could boost office output by more than 1 percent at best. As Progressive Architecture put it in 1980, Stumpf recognized that “people sit right-side-up, sideways, and upside down as they please, lumbar support or no.” His was the first U.S. chair to use a gas cylinder—a German invention—to regulate seat height and help cushion the shock of sitting down.42

  Independently, other designers were pursuing similar goals. Niels Diffrient of Henry Dreyfuss Associates, who had worked with the early medical chair expert Dr. Janet Travell on airline and industrial seating, patented the first knee-tilt mechanism that rotated the sitter’s body back and downward instead of tilting it where the center column met the seat-pan. Feet could now stay on the ground, making deep reclining more comfortable. After studying orthopedic and vascular health, the Argentine-born American polymath Emilio Ambasz and his Italian colleague Giancarlo Piretti introduced the Vertebra Seating System in 1978, a series of chairs with ingeniously hinged backrests and spring-loaded sliding seats that encouraged relaxation. Their patented joints covered with butyl rubber bellows helped define a new high-technology look in chairs.43

  Even as these chairs came to market, offices were changing. The rise of computing was putting terminals and keyboards on the desks of some managers and even executives. But pens, papers, and telephones weren’t going away. The ideal chair would help the body through this growing range of activities, by positively encouraging changes of motion. The Cyborg chair, developed in Denmark by the designer Jacob Jensen and the ergonomist Vibeke Leschly had pneumatic cylinders for adjusting seat height, seat angle, and seat depth. But its greatest innovation was the seat angle cylinder, which automatically and gradually changed the seat back position in response to variations in weight. Users were induced unconsciously to change the position of their spines through about four degrees at the rate of about a degree a minute, so loads on muscles and vertebrae va
ried. By changing points of contact between chair and body, the Cyborg also promoted circulation and prevented muscle tissue malnutrition, according to Rudd International, its U.S. manufacturer. Lifting the body’s weight, even by reaching for a pencil, reset the cylinder for a new cycle. The Cyborg chair went out of production quietly in the early 1990s, no doubt held back by its price of over $1,300. But it showed how much (and how little) attitudes toward body techniques had changed. Like the Domore Postur-Matic, it induced motion gently. But while Domore had discouraged user adjustments and was designed to nudge the occupant back to a single optimal attitude, the Cyborg intentionally and subtly destabilized the sitter, as though symbolizing a shift from high modernism to postmodernity.44

  All these chairs of the late 1970s had one important feature in common. They were advertised for a range of positions and activities; reclining appeared almost as important as upright sitting. And as women sought greater equality in the workplace, secretarial chairs gained more features and adjustments for greater comfort. In fact, Emilio Ambasz told me in the early 1980s that he considered the headrest of his executive model to be a functionless “nimbus” and personally used the secretarial model of the Vertebra chair.

  THE ERGONOMIC EXPLOSION

  From these beginnings the ergonomic seating movement flowered in the 1980s. Once more, the military and the schools led the way. In 1978, the National Aeronautics and Space Administration (NASA) published the Anthropometric Source Book, derived from research on weightlessness in the space program. It determined, among many other dimensions, a natural 128-degree angle between upper body and thighs and between the thighs and the lower legs. NASAs was not the first measurement of weightless posture; an American surgeon named J. J. Keegan had established in 1953 that the natural resting postion of people asleep on their sides with relaxed muscles was a 135-degree angle, and we will see in Chapter Six that European researchers had reached similar conclusions in the 1930s. (Even before them, in 1878, Nature had identified the bamboo veranda chair of colonial India, with its W-shaped profile, as physiologically optimal seating.) But the Anthropometric Source Book was the first work of its kind widely available to engineers and designers. At the same time, a Danish surgeon, A. C. Mandal, alarmed by the rate of increase of back problems in an increasingly sedentary society and aware of Keegan’s work, pointed to the deformation of young backbones by conventional school furniture. Backward-sloping seats with lower-back support were deforming the lumbar spines of children, who spent their time not sitting up like typists but leaning over desks to read, write, and reach for objects, distorting the lumbar spine. Mandal’s solution was also to open up the thigh-trunk angle with a seat that inclined forward 15 degrees and a desk slanted toward the student at 10 degrees. Indeed, he observed that children, and adults with back problems, often tilted chairs forward for relief.45

  While forward-sloping seats had been recommended as early as 1884, the 1980s were their great age. Schools in Scandinavia and France were refurbished with chairs and desks built on Mandal’s principles. And the angle of adult seating was influenced, too. In America, a Texas professor of mechanical engineering and former aviator, Jerome Congleton, designed a new series of chairs now best known under the Bodybilt trademark, with highly contoured seatpans to hold the sitter in place in the angle recommended by NASA and Dr. Mandal. In the late 1970s the Norwegian company Håg introduced the Balans chair, a kneeling stool with a forward-inclined seat and a shin rest that kept the sitter from sliding forward. The Balans, still in production and widely imitated, shows how technology and body techniques can interact. The rise of the personal computer multiplied the number of professionals who sat at keyboards and monitors all day; it also coincided with a rise in back problems caused by poor posture. But like many of the other technologies we have seen, the Balans had to be learned. According to Håg, users need one to four weeks to activate muscles that have not been used in conventional seating. There is also an art to sitting down and getting up. For many people, the Balans chair demands a new set of body skills. Satisfied users found relief from back pain and considered the effort worthwhile; others complained of sore shins and circulation problems. For the first time, abstract ideals of design confronted not only the differences in human dimensions but also those in body habits.46

  The athletic-shoe industry, selling replaceable products to individuals, solved a similar problem by categorizing foot types (low and high arches) and running styles (pronators and supinators) and offering a variety of shoes selling directly to the consumer for $50 to $150. But the ergonomic chair industry was selling $500 to $1,500 durables largely to employers through architects and interior designers with aesthetic as well as physiological goals. When employees have a chance to comment on sample chairs, consensus is rare, if only because (as studies have shown) most users do not study the instructions for adjusting their permanent chairs, let alone each of a number of floor samples. For most athletic shoes, lacing is the only user adjustment; for office chairs of the 1980s, there may be ten or more, including three adjustments of armrests alone. One survey of office workers with adjustable chairs showed that more than half did not know how to adjust tilt tension or back height, and one in five did not even realize the seat height could be raised and lowered.47

  Meanwhile, the spread of computers was changing the body techniques of the office. Until the 1980s, most office workers used computers either almost continuously or not at all. Executives shunned them. As their attitudes changed—and we will see the triumph of the keyboard in Chapter Eight—their body techniques shifted, and they alternated between keyboarding, reading, reaching for the telephone and fax, and talking face-to-face. In fashionable open-plan offices, the totem pole of executive, managerial, and task furniture seemed anachronistic. Like Ambasz, many executives discovered that smaller chairs fitted the new office society. In 1989, the New York Times Magazine featured the Texas billionaire Ross Perot in a cloth-upholstered “manager” version of Klaus Franck and Werner Sauer’s FS chair, designed for Wilkhahn, one of a new generation of seats adjusting automatically to the sitter’s weight and motions. Even Thomas S. Monaghan, the chairman and founder of Domino’s Pizza, was revealed to work not in his $5,000 leather throne but in a “high-quality” armless secretarial chair kept in a tiny private room within his two-story 3,500-square-foot office suite.48

  While many corporations were shedding employees, and income differentials were starting to grow in the United States, designers campaigned successfully for more equal access to seating comfort with minimal adjustments. The chair was supposed to respond to the sitter; active people needed “passive” seating. Herman Miller worked with William Stumpf and Donald Chadwick on the Equa chair (1984), using a one-piece glass-reinforced thermoplastic polyester shell cut out like an H and mounted on a knee-tilt mechanism. When the sitter leaned back, the shell flexed automatically to support both the upper and lower back during reclining. Herman Miller’s neighbor and archrival, Steelcase, introduced the Sensor chair, licensed from the German designer Wolfgang Muller-Deisig in 1986, with sculpted, contoured foam support and a polypropylene shell that flexed with the user’s back. As Muller-Deisig put it, the chair “moves when the body moves.” While available with multiple back heights and fabric grades, the Sensor and the Equa were among the first chairs marketed up and down the corporate ladder, and the first chairs to successfully substitute responsive materials for mechanical linkages. Seating hierarchy became cosmetic; power might bring leather upholstery and a chromed base, not a better mechanism.49

  FLEXIBLE SEATING

  As is often the case in design, especially design for the body, the simple and elegant solutions of the Sensor and the Equa had taken years of painstaking studies, trials, and development work. By the late 1980s, a competitive chair needed not only to be ergonomically sound but also to be comfortable on a first trial and (with a few exceptions like the Balans) to look comfortable. It took the Italian architect Mario Bellini six years to develop his own
body-conforming chair, the Persona, introduced in 1985 by the Swiss firm Vitra and still considered a style leader in its category by many architects.50

  In the dawning twenty-first century, it is no longer new ergonomic theories that produce new seating. Regular changes of position—what the ergonomist Karl Kroemer has called free posturing—have largely replaced the fixation of the older posture movement on uprightness. But there is still a search for new styles of body motion. The most successful and controversial innovation has been the Aeron chair (1994). Designed, like the Equa, by Stumpf and Chadwick, it is also made by Herman Miller. The Aeron took the idea of a full range of body motion farther than any other chair produced by major furniture companies. At the onset of the Internet era, it offered the most boldly technological look in mainstream office seating, with a polymer mesh called a pellicle stretched across a curving molded plastic frame that swelled across the back and shoulders. (This was not as radical an idea as it seemed; some American swivel armchairs even before 1890 had backs and seats of woven cane, fashionable for executive seating.) Even the original Equa had two back heights; the Aeron has large and small variants but they share the proportions of the standard model. The key to the Aeron is an usually deep tilt, up to about 30 degrees, from the ankles rather than from the knees. The sitter’s body rotates away from the desk and down. It takes a powerful spring to balance the chair; the tension knob moves through one hundred revolutions, or up to three hundred turns of the hand. Some ergonomists frown on this, and on the Aeron’s continuous back, which pushes the sitter’s buttocks forward. The pellicle lets air circulate around the body but does not allow full cushioning of the seat edge and needs a movable block for lumbar support.51