From The Ergoweb® Learning Center

Sitting Down on the Job. Comfortably.

 There’s something to be said for a comfortable chair, considering the average office employee spends most of an eight hour day in one.  So it’s no wonder that chairs have become almost as high tech as some of their office equipment counterparts.  No longer is it just spinning, rolling and adjustable height.  Now chairs promise to do everything but make the morning cup of coffee to accommodate the job.


 Seat height, back height, arm rests that move up, down, and sideways, fabric, leather, mesh, lumbar supports, tilts that adjust with the worker, chairs that breathe, foam that remembers the shape of the user (intentionally).  Enough knobs, buttons, gizmos and gears to make any good movie spy jealous.  But when an employer is ready to invest anywhere from forty bucks to well over a grand for a new office chair, which aspects of this comfort dialogue are really important?  That depends on who’s doing the talking.


OSHA’s Sit Down Approach
 There’s no OSHA standard for office chairs just like there is no standard person who sits in a chair.  So just as people come in all shapes, sizes and textures, so do chairs.


 But while OSHA doesn’t have an office chair regulation or requirement, it does offer some recommendations on what to strive for in office seating.


 A properly designed and adjusted chair will provide appropriate support to the back, legs, buttocks and arms. This support can reduce contact stress, over exertion and fatigue. It will also promote proper circulation to the extremities. The following items are critical to an employee who spends extended hours at the workstation: seat position, chair height, armrest.


 The proper adjustment of the chair is related to the proper placement of the monitor, keyboard, mouse and work surface. (From OSHA’s eTools, available at www.osha.gov).


 But aside from listing a few potential hazards in a chair, and recommendations on how to fix the hazards, that’s all OSHA has to say on the subject.  After all, a chair is only as comfortable as the user it’s holding.


From the Manufacturers


 There’s more to a chair than just a simple seat and back or a look that matches an office.  For some manufacturers, introducing a new office chair is a process that involves teams of engineers working with body mechanics to produce the latest seated innovations.


 Ken Tameling, marketing manager for Steelcase, explains the process of developing his company’s Leap chair.


 “It all starts with the user and their needs. This drives the design of the chair. Form follows function,” says Tameling.  And over the years, chairs have changed, Tameling says. “In the back, we’ve gone from fixed backs to fixed contoured backs, to the ‘Live Back.’ In mechanisms, we’ve gone from swivel tilt mechanisms, to synchro tilt mechanisms, to the Natural Glide system. In arms, we’ve gone from fixed arms to height adjustable arms, to arms that telescope, pivot and adjust up and down. With the seat, we’ve gone from a fixed position, to a seat angle adjustment, to a seat edge angle adjustment. We’ve also added seat depth adjustment over the past ten years. We’ve also improved on thermal comfort in today’s chairs with the design of the chair and the materials used. We’ve made chairs more environmentally friendly,” says Tameling.  But to the chair buyer, exactly what does this mean? “Leap provides a healthier way to sit,” says Tameling.


 At Herman Miller, whose Aeron chair is equipped with PostureFit, the goal is similar.  Media rep Sheila Warfield forwarded this information on the PostureFit system: “The PostureFit system was designed to integrate the concept of sacral-pelvic support into the highly ergonomic Aeron work chair by providing custom-fitted support at the base of the spine. The device complements the supportive Pellicle suspension material by working as a lower back support system that the user can adjust to his or her ergonomic needs.”  Or, in lay terms, “A good chair fits the body.”


Where the Difference Sits
  At Neutral Posture, it started with a doctoral dissertation, and the company’s founders building chairs in their garage.


 “We do things a little differently,” says Rebecca Boenigk, Chairman of the Board and CEO of the 15 year old chair company.  “We have never sold a chair because it was pretty,” she says.


 In actuality, the chairs aren’t ugly — they’re just practical.  While the competitors are pumping out breathable mesh numbers in a variety of sexy looks and sizes, Neutral Posture’s chairs look like office chairs. Their model lines are named with numbers — simple ones. The chair is functional and comfortable .


 Neutral Posture’s goal has been the same since the company was born almost 15 years ago — to make chairs that fit into the body’s natural posture.  The original inspiration came from studying astronauts in zero gravity situations and determining the position the body would take without stress.  A fully adjustable one-size-fits-most chair was then designed to accommodate people sized between the 5th and 95th percentile.


 Boenigk says that means a Neutral Posture task chair will adjust for a person from 5 feet tall to 6 feet 4 inches.  “It’s much more difficult to design that way,” says Boenigk. “[Other manufacturers] provide 2.5 inches of adjustment, we’ll provide four,” she says.


 In the competitive office furniture market, each manufacturer strives to set its chair apart from the rest, sometimes with the help of engineering, other times with the help of a good marketing department. The following manufacturer-supplied descriptions are how Herman Miller, Steelcase and Neutral Posture see their chairs in relationship to other chairs on the market:



HermanMiller:  “While many chairs have a lumbar device to improve back support, they are not addressing the root cause of slouching: when the pelvis rotates backward into the ‘void’ or pocket, in between the seat pan and seat back, the spine cannot maintain an upright position. PostureFit applies support at the base of the spine to keep the pelvis rotated forward, which prevents the spine from slouching. No other work chair integrates sacral-pelvic support the way it’s applied to the Aeron work chair. ” — from Herman Miller


Steelcase:  “Leap has a

This article originally appeared in The Ergonomics Report™ on 2002-12-01.