Ergonomics’ Credibility Still in the Works
A scientific discipline that came of age with the ubiquitous use of personal computers is taking some knocks these days, both in the Congress and the science media.
Ergonomics has become a buzzword ever since personal computers began sending users to their doctors with severe wrist pain caused by carpal tunnel syndrome.
At issue is whether the science underlying ergonomics is sound. A bill that is winding its way through Congress would stop the federal government from establishing new regulations for industries until a two-year study by the National Academy of Sciences is completed.
That study, which is just now getting started, is the second time the academy has studied the issue in the past three years.
And a report in the journal Nature questions whether some of the research in the field is valid.
Basically, ergonomics is the attempt to make the world more user-friendly by ensuring that the human-gadget interface is as kind as possible. It ranges from corkscrews to computers, and from control rooms for nuclear power plants to heavy lifting.
As a scientific discipline, the field is only about 50 years old, according to psychologist William C. Howell, who chairs the Committee on Human Factors for the academy’s National Research Council. The term human factors is virtually synonymous with ergonomics, and Howell believes the previous study provided a mountain of evidence that proper design can significantly reduce injuries in the workplace.
That was the conclusion reached by the committee he chairs, and it was echoed by similar studies by the National Institute for Occupational Safety and Health, the General Accounting Office and the U.S. Department of Labor.
But last year Congress appropriated $890,000 and told Howell’s committee to do the study again.
“In my view that’s sort of unnecessary because the evidence has been there for a long time,” said Howell, former science director of the American Psychological Assn.
The congressional demand was precipitated by a move by OSHA to establish guidelines for the use of ergonomics in the workplace.
A Republican-controlled U.S. House subcommittee approved a bill last week that would prohibit OSHA from implementing any guidelines until the new study is completed.
Howell, who spent five years lobbying Congress for the American Psychological Assn., said the move grew out of concerns that guidelines have a way of evolving into regulations and laws that can cost businesses money.
Rep. Roy Blunt (R-Mo.), who sponsored the House bill, said he is not convinced that the subject has been studied enough.
“It’s time OSHA recognize the importance of doing its homework before issuing a regulation,” Blunt said.
Although Howell and others insist the evidence, in most cases, overwhelmingly supports ergonomics, it is less convincing in some areas, and even some experts in the field are uncomfortable with efforts to impose regulations on the workplace.
Some in the field opposed an earlier OSHA proposal because they felt it went beyond the science in some areas.
“There’s still a lot of unanswered questions,” said Howell, “but I don’t think anybody who has seriously reviewed the literature could come to any other conclusion than that there are a lot of workplace situations that present serious risks.”
Even the Santa Monica-based Human Factors & Ergonomics Society has stopped short of endorsing guidelines proposed by OSHA.
“We’re struggling to respond in a way that makes sense,” said Lynn Strother, the society’s executive director.
Part of the problem stems from the fact that even something as fundamental as heavy lifting can get very complicated.
“Specifying exact numbers as to how much a person should lift, for example, is very tricky,” Howell said. “It depends on how they do the lifting and what the circumstances of the lifting are.”
Some of the strongest evidence involves computer workstations, largely because of injuries resulting from highly repetitive use.
A recent study by San Francisco State University found, for example, that people who use a mouse with their computer suffer more than twice as much muscle tension in their arms, necks and shoulders as those who don’t use a mouse.
The problem is exacerbated by wide keyboards that force the user to reach farther for the mouse.
And researchers at Cornell University were shocked recently when they looked at computer workstations in elementary schools.
The stations had been designed with little regard for musculoskeletal development, and according to the study, 40% of the third- to fifth-graders who used the stations were at “postural risk.”
Researchers insist that conclusions such as those are based on sound science and engineering. But they are faced with opposition from some who view the field as “voodoo science,” said the society’s Strother.
Part of the problem may be that the field is being invaded by marketing people with no real background in ergonomics, she said. “I’ve seen ads for ergonomically designed tortilla chips,” Strother said. “I guess that’s the kind that you can scoop up a lot of guacamole without breaking it.”
Researchers in the Engineering Psychology Research Group at the University of Southampton in England found little merit in claims that items ranging from computer keyboards to video recorders were ergonomically designed to be user-friendly.
“Methods for predicting the usability of devices have become so entrenched that their validity is simply assumed and seldom tested,” the researchers said in a commentary in the current issue of the journal Nature.
They did not challenge the validity of ergonomics when it is carried out properly, but they did question whether sound procedures are always followed.
That, however, should have no bearing on efforts to make the workplace safer, said Howell, because the evidence clearly shows that if you can make something easier to use, you can reduce injuries.
But the question remains: Should that be regulated by the federal government, or should common sense prevail over the workplace?
As one past president of the Human Factors & Ergonomics Society noted recently, good ergonomics is good economics. Lost time from preventable injuries lowers production and profits.
Lee Dye can be reached at leedye@compuserve.com.
