Ergonomic Office Chairs

Does Aeron still rule among ergonomic chairs?

The Merriam-Webster Dictionary defines ergonomics as "an applied science concerned with designing and arranging things people use so that the people and things interact most efficiently and safely." Experts say that investing in an ergonomic task chair can increase comfort, boost productivity and help prevent back problems, carpal tunnel syndrome and an array of other physical conditions. The best ergonomic chairs meet or exceed design and construction standards developed by The Business and Institutional Furniture Manufacturer's Association (BIFMA), and are approved by the American National Standards Institute (ANSI). The federal Occupational Safety and Health Administration (OSHA) has also developed ergonomic standards.

No single event has had more impact on the office chair market than the introduction in 1994 of the ergonomically designed Herman Miller Aeron chair (*Est. $630 to $900). It so revolutionized the workplace that the Aeron has earned a spot in New York's Museum of Modern Art and is the subject of a Trivial Pursuit question. A breakthrough in ergonomic seating, the Aeron chair has been praised in reviews not only for its innovative Kinematic tilt feature and easy adjustability, but also for its use of a mesh-like material called Pellicle, which allows air to flow freely through the back and bottom of the chair. The fully equipped Aeron chair (*Est. $630 to $900) had adjustable lumbar depth, lumbar height, tilt tension, seat-pan angle, seat height, armrest angle and armrest height. Aeron chairs are certified by the Greenguard Environmental Institute, which sets standards for chemical and particle emissions from products in order to maintain indoor air quality.

Most reviewers and owners praise the Herman Miller Aeron, but a few people point out that it has some drawbacks. Staffers at Slate.com say that the chair isn't very adaptable. If you like to recline, the Aeron can feel a bit "tippy," and its contoured seat doesn't adapt well to different types of sitting postures. In addition, some testers are annoyed at the number of dials and levers on the Aeron. Owners of the Aeron seem to fall into two camps: those for whom the chair is the perfect fit and those for whom the chair is either too big or too small. The Aeron comes in three sizes: A (small), B (medium) and C (large). If you don't have the size chair that best fits you, the Aeron can be very uncomfortable, say those who have tried them.

The Mirra, a slightly less expensive Herman Miller chair, comes in two versions. The basic version (*Est. $600 to $800) has very few manual adjustments; rather, it has a "harmonic tilt" mechanism that adjusts automatically when you lean back in the chair. The basic Mirra office chair has a fixed seat depth, while the loaded Mirra (*Est. $600 to $800) includes adjustable seat depth, armrests and lumbar support, and a tilt limiter. Unlike the Aeron, the Mirra chair comes in one size designed to shape itself to each user, requiring only minor adjustments to fine-tune the fit. Notably, some Mirra owners posting reviews at Amazon.com say they tested both the Aeron and the Mirra office chairs before buying, choosing the Mirra for its comparable comfort at a somewhat lower price.

Another high-end Herman Miller chair, the Embody (*Est. $1,200), was introduced in 2009. Jason Chen at Gizmodo.com called it "the best chair we've ever sat on," and the design won a 2009 Merit Award from Interior Design magazine. The upholstered Embody chair is large and heavy and its plastic backrest architecture is designed to conform to movement. We found only a handful of user reviews of this chair, perhaps because it's so expensive. The few people who do review it on Amazon.com give it high ratings; most say that it's worth the money. All Herman Miller chairs come with a 12-year warranty.

Two other chairs introduced in 2009 have also made a stir in the industry: the Humanscale Diffrient World (*Est. $740 and up) and the Generation by Knoll (*Est. $650 and up). Both chairs represent the trend toward simpler and greener products, and both have received several prestigious design awards. The Humanscale Diffrient World chair was designed by Niels Diffrient, who also designed the highly successful Humanscale Freedom (*Est. $800 and up) and Liberty (*Est. $760 and up) chairs. According to Humanscale, the Diffrient World chair has only eight major parts, so the manufacturing process is simpler and has less environmental impact -- and, say some experts, there's less to go wrong. There is no tilt tension control; the chair is weight-sensitive and automatically adjusts as you lean back. The back of the chair also pivots with the user's motion, providing support in a range of sitting postures. The mesh seat back responds to the user's body weight and movements but has enough structure to support the back comfortably. The basic chair is armless; you can add fixed arms (*Est. $80) or adjustable arms (*Est. $170). The Diffrient World chair comes in only one size, though you can order base cylinders of different heights, and it carries a 15-year warranty.

The Diffrient World chair won a 2010 Red Dot Best of the Best Award, a 2009 Best of the Year Merit Award from Interior Design magazine, and an FX Award from the International Interior Design Association (IIDA), among others. Since it just went on the market in the summer of 2010, owner reviews are not yet available, but experts who have tried this chair give it high marks so far. For example, a reviewer for SitBetter.com who tried out the Diffrient World chair at the NeoCon World's Trade Fair (an annual contract furniture trade fair) writes that it is "a winner," and "a great value… in the high end seating market."

The Generation chair by Knoll has also garnered design awards, including a Best of NeoCon 2009 Gold Award for Seating and a Best of the Year award for 2009 from Interior Design magazine. This back of the Generation chair, made of a slightly elastic polymer, was designed to be flexible -- if the user turns to glance over his shoulder, the back of the chair bends backward so he or she can sling an arm over it. According to Herman Miller, the Generation chair also uses an eco-friendly manufacturing process and sustainable materials. It is available in a number of colors and materials, from mesh to fabric to leather. It comes with a 10-year warranty.

No user reviews are available yet, but like the Diffrient World chair, the Generation earns excellent reviews from most experts. A reviewer for Bloomberg Businessweek, for example, says she tried this chair out for a few weeks and found it so comfortable that she worries (somewhat facetiously) that chairs like this will encourage people to spend all their time seated. Wired's Maren Jinnett notes that the chair back's elasticity takes a little getting used to, and says the lumbar support is not easy to adjust.

An older chair, the Steelcase Leap (*Est. $850 and up), was introduced in 1999 to compete with the Herman Miller Aeron. It is fully adjustable and has a gliding seat and flexible back that allows the user to recline without pulling away from her desk. It's available in leather or fabric, and while some reviewers say the Leap could blend with many different design styles, Wired's reviewer pronounces it "office-chairy." Owners give it uniformly high ratings for its comfort, back support and adjustability. Steelcase offers a lifetime warranty, with the exception of 10 years for seating mechanisms and three years for fabric.

Another chair released in 1999, Humanscale's Freedom (*Est. $800 and up), has a structure that allows it to adapt to the user's body with few manual adjustments. Unlike those on most other models, the armrests can be positioned below thigh level to slide beneath a desk or tabletop. Like the Steelcase Leap chair, the Freedom comes in just one size, and can be upholstered in leather or fabric. Humanscale offers a five-year warranty on fabric and cushions and a lifetime guarantee on all other parts. Users posting reviews on Amazon.com generally like the Freedom chair, especially its simplicity. One says she's been using it for eight years now and still finds it as comfortable as when she first bought it.