Several large ergonomic epidemiology studies in the U.S. and Europe are nearing completion, according to David Rempel, M.D., MPH, director of the University of California San Francisco Ergonomics Program.
"It is time for the research community to reach consensus on a prioritization of the relevant musculoskeletal risk factors related to computer use," he adds. "We can then focus on intervention studies that address the high priority risk factors. These studies should consider productivity, cost/benefits, psychosocial and work organization factors, vision and lighting. The effect of new technologies must also be evaluated." he added.
Despite the lack of an ergonomics standard, it is still a hot topic of conversation in among safety professionals and a problem that doesn't seem to be going away. The National Institute of Occupational Safety and Health have declared workplace musculoskeletal disorders (MSDs) to be the single largest occupational safety and health problem in the United States.
The American Society of Safety Engineers (ASSE) adds its voice to the chorus, urging employers to develop and implement an effective ergonomic system to reduce those injuries.
"Increased productivity, reduced workers' compensation and health care claims and a decline in the number of lost work-days are just a few of the benefits realized," says Eddie Greer, ASSE president. "Efficient ergonomic systems are a valuable asset for business and increases the United State's ability to compete in a rapidly changing global market."
Last year, Congress overturned the Occupational Safety and Health Administration's (OSHA) ergonomic standard. Some kind of action was promised on ergonomics by Secretary of Labor Elaine Chao for September and then again for "late fall", but nothing has occurred.
ASSE supported the adoption of a federal standard, but did not agree with all of the components of the OSHA standard (see ASSE ergonomic policy at www.asse.org). However, ASSE and its 30,000 members who are occupational safety, health and environmental professionals, acknowledge that many industries, but not enough, saw the positive benefits of ergonomics for their workers and their bottom line and implemented successful programs.
While recognizing that there is no one-size-fits all approach to ergonomics, ASSE recommends the following tips to increase safety and comfort in the workplace:
- Chairs: A chair should have a five-point star base for stability, an adjustable backrest (angle, height, and depth) that provides lumbar support and an adjustable seat pan (height, forward and backward, and tilt angle). Armrests should be padded, adjustable up and down, in and out and swivel (e.g., like a wrist rest). The edge of the seat pan should be at least four inches from the soft tissue area behind the knee.
- Screen: The top of a computer display screen should be slightly below eye level.
- Accessories: A document holder that is the same height and distance from the user as the display screen should be provided when the primary task is data entry.
- Keyboards: Keyboards should be detachable and adjustable to allow straight/parallel hand-forearm posture. This is often accomplished using a wrist rest. ASSE experts recommend that the height of the wrist rest should equal the home row key height. Fingers on the home row of a keyboard should be approximately 0 to one and a half inches above the elbow rest height. The keyboard slope should be no greater than 15 degrees.
- Desk: A desk or tabletop should allow legroom for posture adjustments for the seated worker while also providing a 90-degree angle of the elbow and the work surface. The same is also true regarding the elbow angle for the sit/stand and the standing user.
- Lighting: For lighting and glare, the characters on the computer screen should be brighter than the screen background. Bright light sources in the peripheral field of the computer screen should be avoided. The computer screen should be positioned to avoid glare. By adjusting the window shades and moving or tilting the terminal can help avoid glare and screen reflections.
- Posture: For posture the head should be tilted 15 degrees forward or less to maintain a vertical position. The elbows should be kept close to the body or supported. The lumbar curve of the back should be maintained. Feet should never be allowed to dangle and should always be supported.
- Eyes: Dry eye can occur because people tend to blink less when viewing monitors. Due to this, fatigue can also set in.
ASSE offers several ergonomic publications for sale through its Web site, including "An Ergonomics Guide to Hand Tools" (order #10110), "Ergonomics: How to Design for Ease and Efficiency" (order #10203), "Handbook of Human Factors and Ergonomics"(order #9804), and "Manual Material Handling: Understanding and Preventing Back Trauma" (order #10111).
by Sandy Smith ([email protected])