Keeping The Digitizer Healthy
by Ian Chong CPE
Digitizing workstations are the kind used by graphic artists, CAD
operators, drafters, engineers and technical illustrators. These
workstations have different characteristics than the run of the mill
computer station used by secretaries, administrative assistants word
processors and internet propeller heads, PC or Mac.
The major difference between workstation types is the use of the
digitizing pad and pointing device (puck, pen or touch-screen). The
monitor, keyboard, mouse, chair, table/desk are all pretty consistent
throughout all computer workstations. Within the embroidery industry,
for example, the digitizing pad and puck are commonly used.
Recently, I visited Com-Cepts, a leading edge embroidery company,
located in Seattle, WA. I focused my attention on three digitizing
stations that were used heavily throughout the day. To the owner's
credit, none of the staff displayed any symptomology. That's because he
has worked in shops which gave no thought to the digitizing
workstations. He has worked at stations which have WW II desks with even
older chairs and equipment, in dim light, no layout area and usually in
cramped quarters with expectations of high output. Like many of our
clients, he began to feel some repetitive motion symptomology, and
became concerned.
When Com-Cepts opened, the owner knew he not only wanted a creative
atmosphere, but one which would keep the time consuming, profit eating,
pain inducing and morale depleting occupational/repetitive motion
injuries caused by computer workstations at bay. Com-Cepts is located on
the shores of picturesque Lake Union with a view of the water. Natural
light is important to his graphic artists/digitizers and not
surprisingly glare from the sun along with wash/bounce light also became
an issue.
Tim began by providing his staff with adjustable height, adjustable
angle drafting and digitizing tables, which allow them to stand up and
work when they wish. Good chairs were recommended by a personal friend
who understood the importance of supporting a human body properly for an
entire work day. The chairs have adjustable back height, back tilt, seat
height and even have a forward tilt for those times when you (and we all
do it) want to sit on the front edge of the seat. Lumbar and thoracic
(lower and upper back) support is also good. Breaks are encouraged. None
of this endless hours at a computer stuff. Two or three hours max and
then a break, to allow the body to rejuvenate. Do something different.
Go outside and watch a sailboat docking, get some fresh air. These are
the subtle things that really make a good working environment to keep
RMI in check.
On-screen or touch screen "mousing"
The high tech world of on-screen pointing/digitizing is fraught with
biomechanical problems, and anyone thinking about using this system
without severe workstation design should be wary. Used on a monitor in a
typical vertical position, touch sensitive screens require
hand/wrist/arm/shoulder (upper extremity) flexion and extension. This
means you have to keep your hand and arm up, reaching the screen.
Sometimes you bend your elbow and rest that on the desk for support, but
that means your head moves closer to the screen, so you end up staring
at the screen six inches away from you nose. Eye strain can become
migraine inducing at this distance. We've seen continuous extended reach
cause a myriad of upper extremity pain.
The best thing to do is avoid using a touch-screen in the vertical
position. If you must use a touch screen, build it into a desktop,
tilted at an angle, so that pointing/touching becomes like writing with
a pencil or with your finger. This scenario of course has the problem of
the screen being covered up by the reference material which also takes
up desktop real estate. Typically a high level of frustration
accompanies this set-up, unless reference material is non-existent and
the operator has a clean desktop.
Mouse-Only
Using a mouse-only digitizing system forces the user to maintain a
static hand position for several hours a day without break. Severe
cramping, tendonitis, tenosynovitis and a lot of other maladies all
commonly grouped under "mouse arm" result. This is bio-mechanically
a very at-risk position to hold for long hours.
We have seen severe cases of injury resulting in job changes and
surgical intervention from this type of mouse usage. It's OK to use a
mouse-only set-up. You just can't use it 8 hours a day 5 days a week and
not expect some sort of symptomology to show up in those susceptible to
it.
Digitizing "Puck"
By far the best of the three, especially when used with both hands in
combination with standard mouse (trackball would be better
ergonomically) on a tilted drawing board. This setup and allows one to
move around, use two hands. This set-up works very well for Com-Cepts,
but may require variances for people of different gender, height, weight
and body condition.
The only real concern voiced by the Com-Cepts crew was the shape of
the puck. On close design/ergonomics analysis, the puck does need a
little attention to be even better. Tim has submitted a design which he
would like to the manufacturer, but to no avail. Our design team thinks
an after market design is feasible (any takers?).
What Can You Do to Prevent Repetitive Motion Injuries in Your
Digitizing Staff?
What Com-Cepts did was a good start, but as good as this intervention
is, things change and they must also adapt. Personnel change, they get
older and more susceptible to RMI, equipment changes, work tasks change.
Com-Cepts must keep reviewing the program, querying his staff, replacing
worn equipment, checking if any symptomology is beginning and make
adaptation as an ongoing concern. Because if they doesn't, the insidious
RMI will likely show up in an aging workforce, Maybe not now but maybe
in five years—and at that time it will be much more costly.
Here's What Managers Can Do to Prevent RMI in their Digitizers:
