Working hard smarter

Ergonomist studies how labor tools affect us

By MARK JOHNSON
markjohnson@journalsentinel.com

Posted: Feb. 5, 2007

Richard W. Marklin Jr. lops branches, shovels clay, carves 30-pound cattle femurs, pulls 270-pound manhole covers and studies the workers who make their living performing these tasks.

Human labor is his laboratory.

The 50-year-old professor in Marquette University's mechanical engineering department examines the way we work and the toll that work takes on our joints, muscles and bones. Known as ergonomics, or human factors engineering, Marklin's field takes him from some of mankind's most primitive tools - the shovel and hammer - to some of its most advanced - the computer keyboard and optical scanner.

"As humans, we're very creative," he says. "We were given this very powerful brain, and we can design new products all the time and new tasks. But when new technology is introduced, it also introduces new problems."

While optical scanners greatly reduced checkout time at the grocery store, Marklin says, they required clerks to make the same wrist-lowering motion thousands of times a day at high speed, leading to a class of injuries known as cumulative trauma disorders. Wrist tendons grew sore and inflamed. They deteriorated.

More than a decade ago, Marklin and several colleagues at Ohio State University monitored the forearms and wrists of clerks and recommended the use of multiple scan beams to reduce wrist motion.

These days, Marklin works in the field and in his lab at N. 17th and W. Wells streets, testing the next generation of shovels, screwdrivers, branch loppers and computer keyboards.

He studies workers as they perform utility line tasks requiring so much physical strength that they can be done by only 1% of the population. He measures their oxygen intake to determine the energy they're spending. He measures the amount of effort needed to perform a task, for example the keystroke needed to produce each of these letters (2 to 3 ounces of static force, though most people apply two to 10 times that amount).

Marklin not only studies workers, he joins them. He has carved beef on an "animal disassembly line" and has ridden a bucket truck 70 feet in the air with utility workers.

His brain is so finely tuned to the pitch of work that he seldom passes a crew without noticing something: the way construction laborers bend to lift plywood, the way roofers heft 90-pound bags of shingles as they climb ladders.

His mission addresses the fundamental balancing act of human toil.

"What do you really buy from humans: their minds or their muscles?" says M. Franz Schneider, who has worked in ergonomics for 25 years and is chief executive officer of the Michigan consulting firm Humantech. "A quarter of a century ago, we bought a lot of muscle and very little mind. Today we're looking to buy more mind and less muscle."

That's good news because our muscles have been taking a beating.

Injuries caused by overexertion and repetitive motions have become a quiet plague on the workplace. Two studies by Liberty Mutual found that in 2003 American employers spent $50.8 billion on wages and medical care for workers hurt on the job. Chief financial officers said the top two causes of workers' compensation losses were overexertion and repetitive motion; together they cost more than $16 billion in 2003.

Such is the challenge facing Marklin and others more than half a century after the dawn of ergonomics.

Although the field is said to have started in the 1920s, it was during and immediately after World War II that it flourished. Alphonse Chapanis, one of the founders of ergonomics, discovered that B-17 pilots were crashing on the runway because the two switches controlling landing gear and landing flaps had been placed side by side inviting confusion.

Over the years, ergonomic research not only improved airplane controls, but led to better chairs, keyboards, computer screens, acoustics, lighting and air circulation. In auto factories, nut runners allowed workers to attach all the bolts on a car tire at once, while in the logging industry, new devices reduced chain saw vibrations that were damaging nerves and arteries.

"Ergonomic" became a common term, but also one that is "widely abused, like 'low calorie' or 'organic,' " says Alan Hedge, a Cornell University professor of ergonomics. "You can buy almost any product from hockey skates to BMWs to corn chips with the label 'ergonomic.' "

Liberal use of the term annoys Marklin at Marquette, who sees great value in the science. It was while designing the exterior covers for computers at IBM in the early 1980s that he discovered the field that would become his career. At IBM, human factors engineers were studying how the design of the computers affected the people who used them.

The key word: people.

Focus on people

"Much of engineering is done with inanimate objects," Marklin says, "and there's nothing wrong with that - coffee cups, widgets. Everything we do, the question is: How does it affect the human user?"

Take the shovel. In 2004, Marklin tested an unusual shovel - its blade was perforated with 116 holes. The holes helped diggers dislodge sticky materials.

In an experiment funded by the not-for-profit Electric Power Research Institute, Marklin had 14 We Energies workers test standard and perforated shovels head to head on a clay field 10 meters by 10 meters and half a meter deep. While workers dug, they breathed into masks and wore wireless micro-computers, allowing Marklin to measure their oxygen intake and heart rate.

He found that workers dug 9.5% more clay and used 12% less energy per pound dug when they used the perforated shovel.

The experiment was one of several involving We Energies employees, work in which the utility has shown a keen interest.

"He looks at what the task is, the potential labor savings, the occupational health benefit, breaks them down and looks at what the cost of the new tool would be," says Lori Rolfson, western area manager for We Energies.

A study Marklin conducted with ergonomist Patricia Seeley prompted the utility to buy battery-powered cutters and crimpers, even though they're 10 times more expensive than manual versions. Marklin and Seeley were able to show that the battery-powered tools increased productivity, reduced the risk of injury and would pay for themselves in a year.

Ergonomists expect a new set of challenges from a work force that is growing older, heavier and more dependent on personal digital assistants - a new source of strain on thumbs and hands.

In his office, surrounded by a desk, keyboard and screen that have been precisely shaped and positioned, Marklin is reminded of something Sir Winston Churchill once said:

"We shape our buildings; thereafter they shape us."

From the Feb. 6, 2007 editions of the Milwaukee Journal Sentinel
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