Humanscale Liberty Chair. Around $900 but you can find discounts on the net
Judging by the 30 or so people who showed up for Karen Price’s ergonomic workshop, there are a lot of aches and pains in the offices of Alliant International University. When Karen asked how many people compounded the damage by working in an awkward home office, about half of them sheepishly raised their hands.
This post, which is about two of the biggest problems in home offices, eye strain and aching backs, is for them and for my friend Alexei. As a support engineer for Filemaker, Alexei has a great “fuzzy slipper job” but also a home office that is giving her a pain in the posterior – or perhaps even a CTD. (I’m the one with eye strain – but more about that later.)
There are about 25 different CTD’s – Cumulative Trauma Disorders. But whether it’s tendonitis, carpal tunnel syndrome, tenosynovitis, tennis elbow or Blackberry thumb, a CTD by any name is just as sour. Every single one of them hurts because of damage to soft tissue, and every one occurs as result of the same risk factors:
- Repetitive movements
- Force (including overly forceful typing!)
- Awkward postures
- Contact stress (from resting your arms on the sharp edge of your desk, for example)
- Cold rooms
- Static load (holding the same position for a long time)
The good news is that you can mitigate many of those risk factors, as well as the causes of eye strain, by paying attention to the design of your home office and by altering some of your own bad habits (funny how those darn behavioral modifications keep cropping up in one health discussion after another). This post will talk a bit about each option.
How Do I Know If I Have a CTD?
The short answer is that if it hurts and keeps on hurting, you probably do. Karen Price, who is Director of Risk Assessment for the Hays Companies, says, “If you have pain anywhere for three to five days, pay attention! Don’t assume that it will go away. Sometimes it will, but the most difficult CTD cases I see almost always have to do with problems that could have been dealt with fairly easily if caught early. But by the time they get to me, they may require surgery.”
Most CTD injuries don’t appear out of the blue; they announce themselves gradually. You are working away, and holding the phone seems like a hassle. After awhile, your shoulder and neck feel uncomfortable. Then it really hurts… and you are on your way to being injured. Early warning signs of injury include:
- Pain and discomfort
- Redness and swelling
- Limited movement
- Numbness or tingling
- A pins and needles sensation
When developing design plans, I encourage clients to complain to me about whatever it is that’s annoying them in any room of the house. Paying attention to the hassle-factor is doubly important in a home office.
I look up to Alexei not only because she's a competitive skater and a "geek goddess" when I need help with my Mac, but also because at 5'2", she's an inch taller than me.
An Aching Back
That kind of desk/table/chair arrangement that will work best depends very much on 1) the kind of work the person is doing, and 2) the physical attributes of the individual. Is the person 5’1″ tall, or 6’5″? The answers to those questions will make a lot of difference as to what kind of chair is comfortable, how high the desktop should be, and how the lighting is arranged.
When it comes to the measurements that are used for American product design, Alexei and I are at the bottom end of the “normal” spectrum. The average of height of a white woman in the US is 5′ 4.9″. Product designers use average heights, along with coordinated measurements for reach, leg length, fanny width, etc., in designing all kinds of products.
Thus, Alexei’s height is a major problem at the gym, where designers have probably assumed that most of the exercising is going to be done by men. Alexei told me that one machine, designed to build the upper body, gives her abdominals quite a workout. And if she doesn’t curl her feet around the lower bars of the machine when she lets the weights down, it also works pretty well as a pilot ejector seat!
Alexei and I would fit in better in Nigeria or Japan, where we come in right at the average height for women. As it is, when we go to symphony hall and sit back in our seats, we feel a bit like Lily Tomlin playing Edith Ann! (When your feet dangle in the air, your circulation is impaired and that leads to discomfort and swollen feet. This can be a major problem on airplanes.) Our neighbor, Blake Seely, who is 6’6″, has the opposite problem. He’s on the far end of the normal height spectrum, coming in above the 95th percentile for men. In the US, the average height for men of Blake’s generation is 5’10.4″ – and Blake would be tall even in the Dinaric Alps, where the average male scrapes the clouds at 6’1″. (If you happen to see eye-to-eye with Blake, you might want to check out Tall Paul’s Tall Mall, a website started by a 6’11” architect who couldn’t find a bed or bed sheets that would fit him. Tall Paul has tall office chairs.)
The fact is, anyone whose height, weight or reach puts them at the edge of the anthropometic range is going to have difficulty with chairs. Nearly two decades ago, in the November 1986 Human Factors Society Bulletin, Rani Lueder, CPE, wrote the following about how the standards for table and seat height affect females, particularly short ones like Alexei:
…when the work surface height is fixed, small females sit higher than large males (Burandt and Grandjean, 1963; Floyd and Roberts, 1958; Floyd and Ward, 1964; Langdon, 1965). Langdon (19.65, p.66) notes “in consequence, although the chair is raised to the point where the limbs cannot be accommodated beneath the desk and the feet cannot reach the floor, the operator is well above the keyboard and sits on the edge of the chair, gripping the curved feet of the chair frame with her shoes”.
Think Chair from Steelcase. From $689 to $939 depending on fabric and options.
Ironically, pending seat height recommendations that attempt to address the difficulties of the small female inadvertently increase the potential for the worst case situation, in which her seat is fully jacked up, legs unsupported, yet she must still maintain excessively elevated arms…
To be sure, better (and far more adjustable) chairs have been designed since that article was written, but in most cases, people at the ends of the height spectrum are still going find themselves fighting with their chairs.
In researching this post, I stumbled across the “CrunchGear” blog which has an interesting review of ergonomic office chairs followed by a revealing series of cross-comments between designers who have tried the various chairs discussed. The Think Chair from Steelcase, the Aeron from Herman Miller, and the Liberty Chair from Humanscale all scored points in the reviews. But in the comments, among the raves, you will also see laments like these:
Those chairs look great… until I sit on them. They seem to be designed for the universal 5′6″-5′10″ range, but easily turn into disappointing torture devices and flip-overs for guys my height (6′2″)…
Women have different ergonomic needs than men because the computer-based injuries they sustain tend to be in their neck and shoulders, whereas with men, their pains are usually in the low to mid back. This is because women have a small musculature in their upper bodies that can’t hold her arms out in space for hours and hours a day in a static posture. Unfortunately, most ergonomic chairs don’t help with this, because the arm width is too wide and … not width adjustable…
The Think Chair from Steelcase, a high-end ergonomic office chair priced at $729, has a seat height that adjusts from 16-21 inches. It also has back and seat “flexors” that track with your natural movements, a pneumatically adjustable seat height and is made of sustainable materials.
Herman Miller Aeron Chair. From $679 for the basic model up to around $1300 for top of the line.
However, it has a seat depth of 18 1/2 inches. Alexei’s height makes her a fifth-percentile adult female, which probably means that her buttock to knee length is about 17 inches. Without adding a lumbar pad to push her forward in the chair, Alexei’s feet may be dangling even when she’s sitting all the way back, in contact with the back rest.
The typical solution for that is to add a foot support under the desk. That’s an inexpensive way of dealing with a desk that’s really too high and an otherwise comfortable chair that you don’t want to have to replace. But the foot pad is far from the only – or the best – solution.
Aeron: Petite, Medium or Tall?
Herman Miller designed the Aeron chair to solve the problems of those at the far ends of the height spectrum – both for short people like me and Alexei, and for tall people like our neighbor Blake. The Aeron chair is notable not only for its multiple ergonomic adjustments, but also because it comes in three different sizes. The Herman Miller website even includes a height and weight chart so that you know which size to order. (While checking prices for this post, I discovered a website that offers the genuine Aeron – not a cheap knockoff – at very significantly discounted prices. There’s actually a market for “pre-owned” Aeron chairs!)
Safety Seal Your Work Envelope
The Steelcase Leap, at around $1200 for the leather version and around $700 for cloth, has also gotten good consumer reviews.
The concept of “work envelope” is useful to have in mind as your evaluate your office setup. Sit at your desk and reach your arms out in front of you, and then to the sides. Reach only as far as you can without stretching, leaning or noticing muscle engagement. You want your bones to do most of the work, rather than stressing the muscles and tendons. Visually mark the boundaries of the space you can comfortably reach. That’s your work envelope. Every item that you use over and over again during your time at the desk should be sited within that envelope. That includes things you read, as well as the things you handle regularly.
Here’s a checklist of things of how the things tucked inside that envelope should look:
- Computer monitor – You should not have to lean forward or back to read the screen, nor should you ever have to turn to the side to see it. When your chin line is parallel to the floor and your eyes are gazing straight ahead, they should be falling about an inch above the Zen Stones image at the top of this blog. Your monitor should be about 18 to 24 inches away from your eyes, and it never should be placed in a corner unless your desk is specifically designed to accommodate that option. This placement will also help you avoid eye strain, which more often occurs due to being too close than too far away.
- Documents – Your reading matter should be placed at the same distance and angle from your eyes as your monitor on a paper stand. If you are typing from a document, you should not have to continually swivel your head to go from document to computer monitor. This positioning will also help reduce eye strain because you are not forcing your eyes to refocus when going from document to screen.
- Keyboard – When typing, your wrists should not be bent; your hands should be out in front of you and your elbows should be at your sides. If your wrists are bent so that your hands are reaching up or down, you need to reposition your keyboard. Your wrists should rest comfortably on the table without any pressure points. (If your desk has a sharp edge that presses into your arm, you need a wrist cushion.)
- Mouse – Your mouse pad should be placed a stable surface within your work envelope and you should not have to stretch to reach it. Your wrist be positioned the same way as described above for the keyboard. If you do a lot of mousing, you may find that a trackball or a light pen and tablet provide a more comfortable alternative.
- Phone – Your phone should be easily accessible within your work envelope. If you find yourself attempted to pinch-hold the phone between your cheek and shoulder while you type, you need to either learn to use the speaker phone or purchase a headset.
Eye Strain and Lighting Solutions
If your eyes are burning or tight, if you’re feeling sharp or dull pains, watering, blurring, double vision or headaches you might have eyestrain. And if you do, the likely culprits are your computer monitor and/or your office lighting.
What’s the best kind of lighting for your home office? There’s no one answer to that question because what’s healthiest and most comfortable depends on two things: 1) how the room itself is situated, and 2) what tasks are being done in the course of the work.
For example, a person running a home tailoring or graphic design business needs ample natural light, which usually means south-facing windows. If the room that’s available doesn’t have that kind of light, then they are going to need to provide some full-spectrum task lighting. A variety of “full spectrum” or “daylight” task lights are available. There is also evidence that providing this light helps to prevent or lessen seasonal affective disorder syndrome (SADS), especially if your office is in an interior room that doesn’t receive daylight.
However, if the person in the office happens to be a computer programmer, the advice I gave in the paragraph above is all wrong! Sunlight flooding a computer screen is a recipe for eye strain. In that case, north-facing windows are better. Ambient fluorescent room lighting or incandescent lights directed toward the ceiling, rather than the task, will be a better choice. And if you are working with both papers and computer, you will need a combination of both types of light.
Whatever kind of work you do, you should watch out for these common causes of eye stain:
- Direct glare. Bright light from any source shining directly into your eyes can cause discomfort. Shield your eyes with your hand for a moment and notice whether you feel relief. If you do, you need to add curtains or blinds or redirect the lamp.
- Reflected glare. Sometimes even the reflection of a white shirt on a computer screen can cause a problem, and not just for vision. The worst effect may be that you unconsciously adopt a crabbed posture in an effort to see.
- Contrast. A dark screen surrounded by a bright background such as a window or a lit wall can cause eye fatigue; light letters on a black background are particular offenders. The best solution is to find a way to darken the area around the screen.
Ten Helpful Behavior Changes
- Warm and stretch for 5-10 minutes before starting to work (Yes, even keyboard athletes need a warm up. Karen Price says, “five minutes of warm up each day are more beneficial than a perfectly ergonomic workstation.”)
- Observe the 55/5 rule. If you have been typing or talking on the phone for 55 minutes, get up, change position and do something else for 5 minutes.
- Change positions when you start to feel uncomfortable. (It takes 10 times longer to recover from static load injuries than from other types of CTD injuries.)
- Get up and stretch every hour or so. Don’t forget to take a coffee break or lunch.
- Blink! When we concentrate, our blink rate slows down and eyes tend to get dehydrated. If your eyes start to blur, that’s a likely sign of dehydration. Your doctor or pharmacist can also recommend a sanitary saline solution drop that will restore the edges to your sight.
- Lowering the height of the monitor can help with dry eyes. When you look downward, more of the eye’s surface is covered by the eyelid. That causes you to blink more, and it also causes your eyes to produce more lubrication.
- Follow the “20/20 rule” for your eyes. Every twenty minutes, look twenty feet away for twenty seconds.
- If you wear bifocals, get a special pair of computer glasses that allow you focus at the right distance; you will avoid both eyestrain and the pain in the neck that comes from tipping your head to get the image in focus.
- Read and follow these Ten Principles of Ergonomics by ergonomicist Dan McLeod. His website offers ways to cure the pain, along with nice, clear drawings of how it looks when it’s right and when it’s wrong.
- Stop reading this blog. Go outside, take a walk, breathe, stretch and let a little natural beauty soothe your weary soul.
Chair Reviews and Helpful Links
Lily Tomlin as Edith Ann
You do not have to be good.
You do not have to walk on your knees
for a hundred miles through the desert repenting.
You only have to let the soft animal of your body
love what it loves.
Tell me about despair, yours, and I will tell you mine.
Meanwhile the world goes on.
Meanwhile the sun and the clear pebbles of the rain
are moving across the landscapes,
over the prairies and the deep trees,
the mountains and the rivers.
Meanwhile the wild geese, high in the clean blue air,
are heading home again.
Whoever you are, no matter how lonely,
the world offers itself to your imagination,
calls to you like the wild geese, harsh and exciting -
over and over announcing your place
in the family of things.
- Mary Oliver