every benefit of the doubt. And yet, even after several hours, I simply
could not adjust. “Just a matter of operator retraining” was how one
saleswoman put it after I complained that I kept hitting the return when
I wanted a quote mark. And yet I wasn’t about to gamble $1,800 on a
machine with a keyboard I might forever hate. Ergonomically, I had an
advantage: I was buying just for myself. But a selection committee, made
up of different kinds of prospective users—clerks and executives
alike—is the next best thing to a lone customer shopping with only
himself in mind.
Avoiding the HAL syndrome, your committee should consider, among other
things, the following:
THE SCREEN
For heavy-duty viewing, a terminal or computer should have at least a
nine-inch screen and ideally a twelve incher. I emphasize the words
“heavy-duty.” An executive using a terminal half an hour a week
obviously has needs different from a clerk doing tedious data-entry work
most of the day. Even the executive, however, should have a screen big
enough for unexpectedly long sessions in front of the tube. On the other
hand, suppose a bank teller must view just a few columns of numbers
every now and then; he may never need a screen bigger than a few inches.
Too large a screen, in fact, even in heavy-duty work, may expose one to
glary reflections.
Size preferences can be quirky. I’ll make do for the moment with the
Kaypro’s nine inches, but I wouldn’t mind a bigger screen; another
writer once said he’d like to hook up the same model to a
twenty-one-inch monitor.
The next basic is the color. The two sexes have somewhat different
tastes. Men, says John van Raalte, an RCA scientist, are less sensitive
to colors in the reddish-orange range than are women. That doesn’t mean,
however, that, as a rule, women should automatically have reddish-orange
monitors. For men and women the optimum range of light sensitivity is
usually amber or green. Comfort is high in those ranges, too, at least
for most people.[38]
Footnote 38:
For observations on the merits of various colors, see _Ergonomic
Aspects of Visual Display Terminals_, edited by Etienne Grandjean and
E. Vigliani and published by Taylor & Francis Limited, London, 1982.
Amber screens are popular in Europe, where one study showed a lower
error rate compared to green and other statistics said more users liked
amber.
American computer magazines have breathlessly praised amber. It’s as if
they were fashion publications thrilled by the latest from abroad. But
_some_ U.S. experts question the controls in at least one proamber
study—for example, the number of volunteers, fewer than two dozen. And
Bruce Rupp of IBM points out that it’s harder to produce a steady,
flickerless image with amber than with green. What’s more, an executive
with a company planning to sell amber terminals said screens of that
color burned out faster than did green ones.
Meanwhile, NIOSH says dark characters against a stable white background
are especially promising; and Etienne Grandjean, a leading ergonomist
with many admirers in the labor movement here and in Europe, agrees.
Perhaps there’s a less jarring transition when your eyes move between
the screen and the printed material you may be working with. It sounds
logical enough, and in fact that’s what the Macintosh and many other
computers use. That’s also the display style I saw in the Newspaper
Guild offices in Washington.
“Do you see any flicker?” asked David Eisen, the guild’s research
director, who, in the labor movement, is one of the best-informed people
on VDTs.
I studied the white background.
“The little lines,” I said, “seem to be rolling into each other.”[39]
Footnote 39:
If you don’t want lines on a CRT to seem to be rolling into each other
when you‘re using a bright background, you should worry about
something called a _refresh rate_. That’s the number of times the
picture “repaints” itself on the screen. Etienne Grandjean, the
prominent Swiss expert on VDTs, recommends a rate of at least 80
cycles a second; others say it needn’t be so high. The Xerox 860’s
rate is 70 cycles, according to David Eisen, and that’s better than
average. Still, I noticed the roll, anyway. In a letter to me in
January 1983 Grandjean also recommended a slow phosphor for use with
the white background. That means the images would take longer to
vanish from the screen than they would otherwise—reducing the
perceived flicker.
The machine’s regular operator also saw the roll but said the screen was
comfortable, anyway.
The Guild machine, moreover, a Xerox 860, had the ability to revert to
white letters against a black background, which would have eliminated
the rolling. Would that all screens be as versatile, especially those
used in many tasks or by people with different tastes.
No matter what the task, however, don’t get caught up in terminal
fashion. Stress the basics. Are the characters, for instance, shaped
well? How big? At least .12 inch and preferably .16? Is the =dot matrix=
at least seven by nine? Harry Snyder at Virginia Polytechnic Institute
found that seven-by-nine matrixes produced “significantly fewer errors”
than when subjects worked with those that were five-by-seven. If you
can’t find the information in a machine’s literature, you might use a
magnifying glass to count the number of dots making up the maximum
widths and heights of the characters. Trying the large “N” and several
more letters on my Kay pro, I learned that dot matrix was a mere five by
seven—the bare minimum for light use; for a writer it could be better.
You might also back off twenty inches to see if the dots merge almost
completely into the letters and numbers. Eisen suggests looking for
flaws like “flicker, character blurring at the edges of the screen, and
adequate space between the characters and lines.”[40] Eisen obviously is
looking at VDTs from the viewpoint of the union members. But unionists’
desire for comfort and ease of use often will overlap with employers’
desire for maximum productivity. Woe unto the employer who doesn’t take
advantage of the overlap. In fact, Eisen’s observations here on
keyboards and screens are within the ergonomics mainstream and shouldn’t
be dismissed because of his affiliations.
Footnote 40:
Eisen’s advice on VDTs can be found in the booklet _Humanizing the VDT
Workplace: A Health Manual for Local Officers and Stewards_, published
jointly by the Newspaper Guild and the International Typographical
Union (the price is $1.50 from the Guild, at 1125 15th St., N.W.,
Washington, D.C. 20005).
“The two things you must remember,” sums up Waters, “are legibility and
comfort. You may think at first that a five-by-seven matrix is fine. But
after six months your eyes may say, ‘No, No!’—and you may get headaches
and feel you need new glasses. Actually, you simply may need a better
screen. You’ve just got to consider how often, long, and intensely
you’ll be looking at the tube.”
When shopping around, you also should ask, “How many letters and
numbers—how many columns—can fill the screen?”
For word processing you’ll normally want at least 80 columns across, the
standard. Some screens, like that of the Victor 9000 microcomputer, can
display 132, which can be just the ticket for spreadsheet aficionados
with the right software.
You’ll also want to know if you can highlight selected parts of the
screen, for instance, categories of information stashed away in the
computer. You might use =reverse video=—a light background and dark
characters if your normal background is dark—to keep track of columns
showing names and addresses. Not interested in phone numbers? Then those
columns for the moment would be the normal light-dark combination. In
word processing, reverse video could show you the blocks of texts that
you planned to move or erase or underline.
Two other amenities—more than amenities, in fact—would be easily
reachable and adjustable controls for changing brightness and contrast.
The Kaypro lacks a contrast control, much to my chagrin. At least I can
adjust brightness—a “must” normally and one still “mustier” for people
using antiglare filters, which reduce light from the screen.
Keep thinking what you or others will most use the computer for. Color
graphics? Fine. But your multicolor monitor won’t display characters as
sharply as a black-and-white or =monochrome= screen would, and the
screens might lose their crispness faster and add to the eyestrain of
heavy word processing. One-color screens, then, would be best for
typical writers and secretaries. On the other hand, if you’re an
executive or clerk working with many figures alongside each other, the
color monitor might help you and your eyes keep the numbers apart.
Might. Some people may object to color except for graphics.
Two kinds of color monitors are common. The =composite= monitor is
technically more like a home TV than the =RGB= or “red/green/blue” kind.
It’s cheaper. But colors blur into each other more than with the latter
type.
Whatever monitor you buy, keep the screen clean.
And don’t be surprised if, in a year or so, the characters start looking
a little fuzzy. Harry Snyder, a leading expert on the ergonomics of
monitors, says the half-life of a tube in heavy use is normally about a
year. Don’t stint on replacements and jack up your people’s error rates.
THE KEYBOARD
Remember Raquel toiling at a keyboard attached to her computer?
Maybe she’s happy. She may have a well-built back, a graceful, flexible
neck, wrists that don’t quit, or simply a body compatible with her
machine and furniture. But I still question the attached board for most
people.
Unless Raquel spent many hours on the machine before buying it, she
might not have known if she’d be comfortable.
The more time you spend at a keyboard, the more likely you‘ll end up
with the right one. Test keyboards thoroughly. If you‘re buying several
dozen, you or a staffer might spend a good three or four hours with the
machine you’re about to purchase. A difference of just 10 percent or so
in the number of keystrokes per hour per operator could mean thousands
of dollars annually to your business.
Even if you’re buying a machine just for your own use, you should still
put in a good half hour checking out the keyboard. That’s true with any
computer. But the odds are stacked against you if you buy one with an
attached board. In Norway, in effect, computer keyboards by law must be
detachable, and in Germany official standards require them in most cases
(an exception exists for, among other things, limited-use portables with
built-in screens and keyboards).[41] Increasingly, union people here are
raising the issue—and quite justifiably, considering the feeling of most
ergonomics experts. Detachable keyboards, in fact, were one of the
issues over which a California union struck the local Blue Cross-Blue
Shield organization.
Footnote 41:
The German requirement for detachable keyboards appears in paragraph
4.3.1 of Standard ZH1/618 of “Safety Regulations for Display
Workplaces in the Office Sector,” as released by the Trade Cooperative
Association, Central Office for Accident Prevention and Industrial
Medicine.
“Well,” you ask, “what about keyboards on infrequently used machines?”
You might, however, end up using the keyboard more often than you
expected. So play it safe. Make all boards detachable. It won’t cost
that much more. Also, keep the cords at least four feet long. And
unstrap the keyboards from the VDTs in the first place—which sounds
insultingly elementary, except that I’ve heard of an absentminded
company that, until a labor dispute, had forgotten to do so.
Also, don’t let the best keyboards become status symbols in reverse. A
well-meaning but wrong executive on the West Coast brags he does _not_
have a terminal with even a good board. He’s a fast typist but thinks he
could spend his time better giving dictation. “An executive typing,” he
says, “is like hiring a brain surgeon to give out pills for a sore
throat. If you’re paying him $50,000 a year, why should he do a $20,000
job two hours a day?”
Most executives would agree. But this is rapidly changing; more and more
executives are tapping out spreadsheets and eventually will do their own
word processing. They may bat out rough drafts on computers or word
processors, then have secretaries whip the documents into shape
electronically without having to retype all of them.
Besides, you can learn typing at any age. And you needn’t be an
excellent typist for computers to help you; indeed, with mistakes easier
to zap, the worst typists will profit the most. Take a Maryland
architect-consultant named Jess McIlvain. Before he got an IBM PC, he
just couldn’t write or type at length—worrying that the result “looked
like the cat had walked over it.” Two years later he was cranking out
reports several hundred pages long.[42]
Footnote 42:
The McIlvain example comes from _PC Magazine_, May 29, 1984.
The new breed of managers, of course, may feel at home on the keyboard
from day one. Some colleges even now require students to buy computers,
many of which they’ll almost certainly use for word processing. What’s
more, as you’ll read in Chapter 11, executive keyboards can ease the
transition in the future to telecommuting.
So don’t impose your own work habits on a junior executive with fast
fingers. Why shouldn’t he or she have a deluxe keyboard if it helps him
serve your company better? And you yourself shouldn’t feel awkward with
at least a good board for quick memos.
Mysteriously, IBM forsook the Selectric tradition in designing the
keyboard of its original Personal Computer, where the left shift key,
oddly, isn’t immediately next to the “Z.” The deviation left some
computer magazine editors flabbergasted. Companies even started making
keyboards for the PC—at several hundred dollars apiece—that retained the
traditional layout.
“They’re not like normal keys,” my consultant friend Michael Canyes
complained of the ones on the PC itself. “They click on and off like
switches.
“A good key,” he said, “gets stiffer as you press down. But the IBM’s
are either up or down.”
Some cynics have a theory. Maybe IBM didn’t want the PC to steal too
many customers away from the Displaywriter costing several thousand
dollars more. Yes, keyboards are a matter of taste, and unlike Michael,
I can stomach the switchlike =tactile feedback=. But the shift location
is inexcusable. IBM in effect admitted its goof; the IBM AT, a more
powerful cousin of the IBM PC and XT, appeared with a much-improved
keyboard.
At least the original IBM PC’s keyboard surpassed that of the tiny,
chiclet keys on the first PC_Jrs._ Reluctantly—after sales were
flagging—IBM replaced the chiclet-style boards with more conventional
ones.
Pity us “users.” Even terminals intended for mainframes and minis can be
turkeys. I actually favor my Kaypro board over a terminal—from Digital
Equipment Corporation—which Waters once was using with a big mini at
work. Blame the old-style programmers who didn’t grow up with word
processing. “Most can’t type like a secretary,” says Canyes, “so the
manufacturers often skimp on the touch.”
And isn’t it strange? You can buy an electric typewriter with adjustable
touch for $200 but not get it in a computer costing fifty times as much.
I asked David Eisen why he hadn’t raised the touch issue. Wouldn’t bad
keyboard matches hurt productivity?
“That’s more the companies’ problem,” he said. “We’re more worried about
health.” He can’t recall a flood of complaints from Guild members about
keyboards with the wrong touch.
Union people, however, have talked about another change, flat keyboards,
now popular in Europe. The tops of U.S. boards commonly slant at fifteen
degrees. And Waters tells of an experiment where, given the ability to
change the angle, most participants settled for the fifteen-degree one.
A caveat, however, is in order. Maybe the people ultimately would have
done better with a flat board and plenty of practice on it. Perhaps you
want an adjustable board. But for me, anyway, it won’t matter as much as
touch.
Another issue is the QWERTY keyboard versus the more modern layouts.
“QWERTY” means the first six letters found on the boards of nearly all
American computers and typewriters. It’s a nineteenth-century legacy—a
bad one. The early typewriters couldn’t keep up with the nimbler
typists, so the machines’ designers thwarted the humans. QWERTY isn’t
alphabetical, it doesn’t bring together commonly used letters like “t,”
“h,” and “e,” nor does it use finger muscles properly. The Dvorak board
and other latecomers should work better. In practice, though, they might
confuse typists, so here’s a solution. Let us old-fashioned people
QWERTY away. But think about buying machines you can switch over for
people trained on more efficient layouts. A program like Smartkey—which
electronically changes the keyboard—might be the answer if you also
relabel keys on machines used by Dvorak typists. The Apple II(c) even
has a switch on the top of the machine to go from QWERTY to Dvorak. Some
say the Dvorak improvement is dramatic. Waters isn’t so sure. He says
some studies have indicated that the Dvorak board offers as little as a
5 percent increase in speed and little reduction of errors. “So in the
end,” says Waters, “most people in the industry have decided not to
tinker with the key arrangement.”
No matter how they’re arranged, your keys shouldn’t be shiny; a matte
surface is good. So are neutral colors rather than black and white,
except, says Eisen, for function keys. My Kaypro sins. Its keys, like
those on Digital Equipment’s VT100, are a gleaming black, which,
however, doesn’t matter that much to me, since I can control my lighting
and normally don’t look down at the board when I’m typing. (Some other
Kaypros have black matte keys.)
Function keys—the ones that let the operator delete a word or add a
paragraph with a single touch—should ideally be a different color from
the main keyboard’s. The same for number pads. The function keys if
possible should have labels indicating their purpose. If not, a chart
near the function keys might show, for instance, that “P1” “Deletes
Word.”
Some people, however, say that function keys really slow you down, that
they make you take your fingers off the main keyboard. I basically
agree. The same would hold true for the use of Macintosh-style mice.
SPECIAL ERGONOMIC FEATURES
A dream VDT tilts. It swivels. It can move up and down on a pedestal. It
helps you avoid back strain, stiff necks, glare, and headaches. It
adjusts, so you don’t have to. A good VDT can help compensate somewhat
if you lack ...
Good Furniture
“People will adapt very nicely to automation,” an IBM official once
said, “if their arms are broken, and we’re in the twisting stage now.”
That was in 1975. Since then, however, in a literal way, some computer
makers have been gentler with people’s arms—and wrists and backs.
A variety of good computer furniture exists now, some in walnut, some in
formica. With all the trimmings, you can vary:
1. The heights of the keyboard and of the computer or terminal.
2. How far the keyboard platform protrudes from the platform on which
the computer rests.
3. The tilt of the computer—a useful glare-reducing feature.
4. The angle at which the screen faces you. You can swivel away to your
heart’s content to suit your posture or cut back on glare.
5. The height of your chair. You don’t of course need high-tech
furniture to do that—just common sense. For a computer operator, says
David Eisen of the Newspaper Guild, a straight-back chair can become
“a ticket to the orthopedic ward.”
You might also shop for a palm rest and, if you’re short, a leg rest.
An easellike copy holder could help as well.
And so can enough desk surface, shelves, or file cabinets for your
paperwork. Why buy a detachable keyboard if you can’t move it around
because your desk is too cluttered?
Jon Ryburg, an ergonomics expert with the Facility Management Institute,
a Michigan think tank owned by Herman Miller furniture, says computer
gear may take up as much as 40 percent of a desktop. And yet does the
space requirement for paperwork decline by that percentage? Hardly. So
unless you enjoy seeing chairs used as desks, you’d better plan your
furniture well.
Not that all improvisation is bad, especially if you’re a professional
or small businessman working at home. My Kaypro, for instance, rests
atop an old carton from a toy store, and I’ve bought some little gray
legs, the color of the case, to tilt the screen back.
That takes care of my ergonomics. Of course, my requirements in this
case aren’t the same as those of a company with dozens of VDT users.
Joan’s old supervisor at the insurance company might scowl at this
haywire, but so far I’m comfortable. I would be much less casual about
buying furniture for others. For example, I’d make certain that the
chairs and tables would be not just adjustable but easily so—and
understandably so. Even an IBM salesman couldn’t puzzle out all the ways
to adjust the ergonomic furniture on which a Displaywriter sat. Despite
such a flaw, however, special computer furniture isn’t just a frill. An
ergonomic desk and chair might cost several hundred dollars more than an
ordinary set—even a lesser-known brand may—but your furniture could be
good for a decade. And just a 5 percent increase in a cleric’s
productivity may pay back the extra investment in less than two years.
At the least, buy an adjustable chair and, ideally, a table of variable
height. “A very short woman,” argues Bob Waters, “may sit with her eyes
almost a foot closer to the floor than a six-foot-two-inch man’s.” The
home-row keys on the keyboard—the row including the letters A, S, D, and
so on—could be twenty-nine or thirty inches above the floor in a
_typical_ case.[43] Other measurements? Upper screen-eye distance: 17¼
to 19¾ inches. Center of the screen: 10-20 degrees below the horizontal
plane of the operator’s eyes. Angle between upper and lower arms:
between 80 and 120 degrees. Wrist angle: 10 degrees or less. The
keyboard is at or below elbow height, and the table allows enough room
for your legs.
Footnote 43:
The advice on keyboard height is from Military Standard 1472C, _Human
Engineering Design Criteria for Military Systems Equipment and
Facilities_, published by the army in May 1981 and summarized in the
July 1982 _Popular Computing_.
Your goal, of course, isn’t to make anyone fit the charts showing
average distances. It’s just to keep people productive and comfortable.
Above all, when shopping around to do this, be skeptical. “A lot of
so-called ergonomic things,” says Waters, “aren’t ergonomic at all.” He
grimaces when he sees $300 wooden tables with fixed-level platforms for
computer monitors. They’re an expensive way to strain your neck. “The
normal line of sight for human beings is fifteen degrees below
horizontal,” Waters says. “People normally look slightly down even when
they hold their heads up.” Needless to say, you and your neck will come
out ahead if, using an old Apple II, you don’t set the monitor atop disk
drives resting on the computer. Ignore the ads showing this compact
pile. Their purpose is to sell computers, not save necks.
Lighting
Bright fluorescents are to computer users’ eyes what a _drip, drip,
drip_, is to the foreheads of Chinese water-torture victims.
They’re rude, persistent distractions.
And as with the water torture, the fluorescents’ victims may be captives
of sorts. How many people can dictate the lighting in their companies’
offices? Many. But not all. So the letters and numbers on their screens,
the facts they need to do their jobs, may compete with the glare beamed
off the glass.
What’s more, the culprit needn’t be just the fluorescents that light so
many American offices.
“The window with sunshine streaming in may still be a psychologically
gratifying link with the outside world,” says Eisen, “but it spells
plain eyestrain and perhaps headache for every VDT operator within range
of the glare.” Even brightly painted walls can sin here.