OSHA claims an ergonomics rule is necessary to prevent “musculoskeletal disorders” such as carpal tunnel syndrome, which purportedly is caused by typing. To date, OSHA has attempted to force ergonomic changes through the “general duty clause” of the OSHA statute, which authorizes that agency to order job changes when it shows that workplace conditions constitute a “recognized hazard” of “death or serious physical harm.” The proposed rule shifts the burden of identifying ergonomic hazards and solutions from OSHA to employers; it would greatly strengthen OSHA’s hand in prosecution.
Under the proposed rule, employers’ obligations would be triggered by “symptoms” of musculoskeletal disorders, which OSHA defines to include “pain,” “numbness” and “tingling.” When those symptoms occur, employers are to determine whether the jobs in question are “reasonably likely” to be ergonomically hazardous. If they are, employers are to implement draconian abatement measures, such as reducing assembly line speeds and redesigning equipment, until the “hazard” is gone.
This vague and subjective rule would afford little benefit to workers because it is based on thoroughly unreliable science. A very simple way of appreciating the folly of ergonomic regulation is to examine OSHA’s own attempts to apply ergonomic principles in the cases it has already litigated to judgment. The three cases highlight three fundamental problems with ergonomics.
First, ergonomists cannot establish when — if ever — demanding physical exertion causes actual injury to the musculoskeletal system. In the Beverly Enterprises case, OSHA sought to prevent nursing home employees from lifting residents to care for them or move them about their rooms. Despite a month-long trial and parade of OSHA experts, a judge found that “there is no reliable epidemiological evidence establishing lifting as a cause of [low back pain]” and that “science has not been successful in showing when and under what circumstances lifting presents significant risk of harm.” One of OSHA’s own experts admitted that the “lifetime incidence of back pain” for teachers is higher than for nursing assistants. Since 80 percent of Americans experience back pain, it is not surprising that OSHA could not link back pain to any particular task.
OSHA’s difficulty is even less surprising in light of a 1992 government study of supposed repetitive motion injuries at a major telecommunications company. The study found that the two factors associated with lower rates of injury were overtime worked and increased hours per day performing data entry. In other words, more repetitive motion meant fewer complaints. Increased complaints were associated with psychological factors such as dissatisfaction with co-workers and supervisors.
Second, even assuming that repetitive work motions can cause injury, ergonomists cannot establish in any given case whether an ailment was caused by work or by genetic factors or other activities, such as sports. In the Dayton Tire case, OSHA targeted 22 supposedly dangerous jobs. But in a 1998 decision a judge found that OSHA expert witnesses had failed to account for many other possible causes of workers’ reported ailments, including non-work activities and prior injuries. The judge deemed OSHA’s methods “junk science” by the standards established in the Supreme Court’s 1993 Daubert decision, and also found repeated inconsistencies among OSHA’s own witnesses: Each of OSHA’s supposed experts had a different theory about what made a job dangerous and what would fix it.
Third, ergonomists cannot reliably identify solutions for perceived ergonomic problems. In the 1997 Pepperidge Farm case, OSHA alleged that workers faced “death or serious physical harm” from lifting the top of a sandwich cookie from one assembly line and placing it on the bottom of the cookie on another assembly line. OSHA also said it was dangerous to use one’s thumb to flick a paper cup onto a conveyer belt and then place a cookie in the cup. It ordered the company to increase staffing, slow assembly line speeds, increase rest periods or simply automate the entire operation. But at trial OSHA could not demonstrate that any of those measures was a feasible and effective means of reducing musculoskeletal disorders at the worksite.
Instead of backing down after those embarrassing losses, OSHA wants to entrench the questionable science of ergonomics in a permanent rule. But no agency should be permitted to impose on the entire American economy a costly rule premised on a “science” so mysterious that the agency itself cannot fathom it.