A great deal of research and many studies have been conducted by Cornell University on what makes a good ergonomic workstation. You can find a comprehensive check list for arranging a Computer Work Station by Cornell University here: http://ergo.human.cornell.edu/ergoguide.html
Many people do not fully understand the requirements necessary for a great ergonomic desk chair. Often the overall style and “sexiness” of the chair trumps the functional importance of a truly ergonomic task chair because visually they are not always the most “cool” style of chairs on the market.
We wanted to provide a quick series of check points which should help you to select a truly ergonomic Desk chair.
Arms: You need them. I am amazed at the number of requests we get for armless chairs. Cornell released this paper on armless desk chairs:
Reduces keying forces during typing typing (Rose, 1991)
Source: http://ergo.human.cornell.edu/Pub/HFPresentations/HFESchair.pdf
Chair seat cushion: The shape of the seat cushion affects your posture. The most common cushion seen in the US is a fairly modest one with a waterfall seat. Extreme sculpted seat cushions are offered mostly on big and tall ergonomic chairs. There are a lot of flat seats on the market that cater to the sleek design demand. The flat seat usually features an ergonomic front water fall edge. The difference between a flat seat and sculpted seat cushion has to do with posture. Some say the seat cushions offering some sculpting prevent “secretarial spread. (meaning that placing weight on something flat will cause it to spread over time).A little know fact is that a chair seat pan that has a bit of rise in back of the seat structure will help to place your spine in a better and more comfortable ergonomic position. If you don’t understand all the pros and cons of the seat shape you won’t know why chairs don’t feel comfortable. The build of the cushion supporting you is also a major factor in terms of comfort and longevity. Cheap chairs (Office Depot, Ikea) are like sitting on cardboard. They wear out quickly and are not rated for an 8 hour work day. Quality chairs will offer the proper foam rating, testing and proper design. You can’t make a worker’s comp claim if you don’t have a contract rating for an 8 hour day.
Mesh Chairs: Mesh back chairs with upholstered seats generally deliver a higher degree of ergonomic support and comfort. The all mesh seat and back chair models are further away from a true ergonomic chair. A chair that offers you all the adjustments you need in every direction to fit your body type and sitting work presence, is ergonomic. The less adjustments and controls available the less ergonomic the chair. The chair may feel great for your body type but if you are sitting steadily at your chair for an 8 hour plus work day make sure that it will remain comfortable in the long run. You must decide what is most important to you: Ergonomics, Style, or a hybrid that offers you enough of both.
Chair backs: Make sure that the chair back provides at least a true 90 degree upright support. We don’t understand chair manufacturers that sell chairs for style only with backs that lean so impractically far back that you can never use that feature! Mesh backs come in wide degrees of stiffness and can have a stretchy knit back. The stiffer mesh types will give your back more support. Knit back meshes are softer but with less support. Upholstered backs generally offer more support but it depends on the shape and the sculpting. Chair backs that offer height and pitch adjustments score higher on the ergonomic comfort level. Fixed backs may or may not fit your body type and comfort preference. Lumbar support on chair backs have a bump which may or may not work with your back’s contour. If you have a height adjustable back you have some degree of control over where that bump may rest. Caution: concave chair backs offer no lumbar support or lower back support and may actually hurt when you sit in them—but we’ve seen these concave chairs in conference chairs and visitor’s side chairs.
Chair Seat Tilt Mechanisms: The basic chair tilt is called a center pivot. It’s the most economical for tight budgets. The center pivot allows for independent tilting of the seat and back. The knee tilt offers a comfortable free float feel when you lean back. The knee tilt is more costly but worth it for the additional comfort. Synchro Tilts are offered in many versions which usually combine the seat tilt with back tilt in specific, designed ratios. Synchro Tilts are also very comfortable.
Drafting Chairs for standing height desks and tables: Arm rests may be more important on a drafting stool because you are pitched higher on the chair. The arms aid in getting in and out of the chair and can help you from accidentally falling off the chair. Chair cylinders come in tall and medium heights . Tall cylinders raise the seat to maximum heights typically accommodating 42” standing height desks. The medium stools heights are for lower surfaces. A quick selection quide: the chair seat should be 12” below the work surface. Drafting chairs are standard with foot rings which are offered as adjustable or fixed. We recommend using a platform under the standing desk that is specially designed to allow you to extend your feet out in front of you as if you were sitting at a normal height desk. This is more comfortable than bending your knees to reach the foot ring. Most drafting chairs offer no seat tilt and rarely offer a back tilt option.
Upholstery on task chairs: Make sure it’s breathable and that the fabric has give and/or stretch.. Ordering a tight woven fabric will negate any benefits of seat foam and shape. Real leather breathes, unlike a good majority of faux leathers/ vinyls. Technologically advanced faux leathers that feel like leather are offered in a higher price ranges.
We hope that these few pointers will help you to better understand the form and the function that governs the chairs you choose.
Mar is always happy to discuss chair options to meet your needs.
