The standard height desk in the furniture industry is 29” and has been that way for a long…time. Post World War II, the government decided to implement some new building standards. The primary information they used to develop these standards was a military study, male only…no women. Please consider that your typical soldier is not like your average civilian walking down the street…think big “burly boys.”
From this study the government decided for one that doorways should be 30” wide. The furniture industry’s response to this standard was to create desk at 29” high so that they could be “flipped sideways” to enable them to pass through doorways during installations.
Doorways today are obviously wider to meet ADA compliance however outside of adjustable height desk; the 29” high standard has never changed. The only problem with this standard is that a 29” worksurface is scaled to a 6’3” individual. The following chart is from ANSI/BIFMA which advocates regulatory conditions for the furniture industry.
As you can see, a woman in the 95% percentile is approximately 5’10” and it’s recommended that her keying height only be 27”…2” below the standard of 29”. For men at the 95th percentile, their recommended keying height is 29.2″ or just over the standard of 29”. Bottom line, if you’re less than 6’3” which constitutes the majority of end users in the market, the standard height desk is too tall for you to hit the ideal postures shown in the following:
The key positions to consider start with the feet which should be flat on the floor or on a footstool. Footstools are a valid tool in allowing the end user to adjust their chair higher while maintaining proper lower body positions. This includes the line from the hip to the knee maintaining a roughly parallel position to the floor. A slight shift forward or back is allowable and actually desirable for sake of putting your body in varied positions throughout the day.
The forearms should be parallel to the floor with your wrist flat and elbows by your sides. The is a key position which fosters the shoulders staying relaxed which directly ties into the upper back. If the elbows are extended forward due to reaching for your keyboard, the shoulders will automatically be elevated engaging the entire upper back musculature. This position creates stress that over a period of time can create significant pain and injury.
The spine should stay in its natural S Curve with no slouching forward. The spine is actually extremely resilient to sheer forces when in its natural S Curve. However, when the spine is out of position which commonly occurs in the way of slouching forward, the spinal disks are at far greater risk for eventual injury.
Your spine is like a “coat hanger” in that it is designed to bend to allow your body to move naturally. However like a coat hanger, it will only take so many “bends” before it “breaks”. Excessive forward slouching which is considered “flexion” is one of the primary injury mechanisms that can lead to a ruptured spinal disk. For optimal spinal health, it is vital to maintain the natural S Curve position as much as possible.
The furniture industry has by offering only the standard height 29” desk for all these years essentially asked the end user to adapt their body to fit the desk. This makes as much sense as clothing stores offering a one size fits all where you just make the best of however the “one” size fits you. Furniture solutions should be adaptable to the end user just like buying clothes to fit “your” body.
The gold standard solution is the adjustable height desk which allows the end user to dial in the right height for the worksurface whether sitting or standing. We are not designed to sit or stand all day. Our bodies crave movement and the adjustable height desk allows for this needed variety.
So what if switching to an adjustable height desk is not an option? ANSI/BIFMA recommends at least two points of adjustment with the keyboard tray and monitor arm being your first line of offense. By integrating a quality keyboard platform and adjustable monitor arm, the end user can largely bridge the gap and achieve the proper ergonomic positions while seated.
This however is only a “half” solution because it does not address the challenge of sitting. The dangers of sitting are one of the hottest topics in current literature as more and more attention is being given to the damage that excessive sitting can do to the body. This is why the adjustable height desk remains the best option. It allows the best of both worlds where the end user can determine their ideal ratio of sitting to standing based on their individual needs.
Closing Remarks for My Readers
How much do you currently sit throughout the day? Remember, ergonomics is not confined to the office. From the moment we get up in the mornings until we go to bed at night, everything we do with our bodies is either helping or hurting from an ergonomic standpoint. In particular, all of the sitting we do is cumulative and the damage adds up.
If you have pain of any sort now, unless you make a change, it’s not going away.
If you have doubts or questions about your current work set up, please let me know how I can help. As a certified ergonomic assessment specialist, I do workplace evaluation for my clients on a regular basis and always welcome new opportunities to serve and help.
For further reference, please go to The Ergonomically Positioned Workcenter for more comprehensive guidelines regarding the proper setup for your work space.