Ergonomics: The study of the interface (or interaction) between humans and the objects they use and the environments in which they function.
 
The definition of ergonomics is one thing but the benefits of good ergonomics is another. Reducing work-related injuries, due to ergonomic problems results in less time lost, reduced health care and worker�s compensation costs, as well as improved morale and productivity.
 
Instituting good ergonomic practices does not have to be a costly and time-consuming practice. Before hiring a consultant, you should perform an evaluation of your operation. Most of us walk through the workplace every day without really �seeing� the jobs performed. A checklist can help you identify ergonomic problems that may merit further attention.
 
Do your own ergonomic audit
�           Does the worker look uncomfortable and awkward?
�           Are the worker�s elbows sticking out (chicken wings), indicating the table may be too high or the chair too low?
�           Is excess effort required?
�           Are there frequent repetitive motions?
�           If the worker must stand for prolonged periods of time, is there a fatigue mat on the floor?
�           Does the worker wear proper footwear?
�           Is there a place to sit down when equipment is running well or there�s a break in activity?
�           Is the worker�s use of a video display terminal more than four hours a day?
�           Is there light or sun glare on video terminals?
�           Can a seated worker reach the floor or footstool?
�           Is the worker�s seat adjustable, and does it have five legs to prevent tipping?
�           Is the workplace noisy, too cold or too hot?
�           Does the job require bending and lifting, indicating the need for lifting devices?
�           Is there excess twisting, bending and reaching indicating poor layout?
�           Is there sufficient light to perform visual tasks?
�           Can the workers rotate jobs so they are not in the same positions all day?
�           Are rest periods required?
�           Is the worker able to frequently change position?
�           Do workers complain about fatigue?
�           Is housekeeping poor?
 
Some specific actions you can take to further identify possible ergonomic problems and solutions are as follows.
 
Find out what hurts
Ergonomists have developed instruments for determining risk factors, but their results are only about half as accurate as simply asking the worker where it hurts. Get your workers together in a group and brainstorm about their jobs. The workers are the real experts in determining whether or not an ergonomic solution works.
 
Head-to-toe analysis
Systematically analyze the worker in a given situation by starting at the head and working your way down.
Ears. Is the operation noisy? There are specific Occupational Safety and Health Administration (OSHA) standards on the maximum levels of noise that are tolerable over various time periods. You can have an audiologist take measurements, but, in my view, if you think your operation is noisy, require your employees to wear earplugs.
 
Eyes. Is there enough light to read and pick orders? Is the print contrast good enough? Are workers taping cardboard on video display terminals to keep glare off the screen?
 
Back. The most frequent cause of lost timework injuries are back problems. Incorrect lifting is a major problem. Employers can train workers to lift correctly by bending at the knees and going straight down then up or, better yet, eliminate lifting through the use of lifting devices. Call a material-handling vendor and expose yourself to whole catalogs of ideas. If you must lift, follow the National Institute of Occupational Safety and Health (NIOSH) lifting formulas.
 
Standing is also hard on the back, yet many jobs cannot be done sitting down. The first ergonomists were Wild West saloon owners who discovered a bar rail allowed cowboys to rest their feet that permitted them to periodically change the loading on their backs. This same bar rail principle should be used at workstations where standing is required. Relief can also be achieved through periodic use of a stool or sit-stand.
 
Arms. For light-duty work, the arms should be parallel to the worktable. Worktables should be adjustable. Table 1 shows the appropriate worktable height for various activities. These are general ranges, and the actual height of the worktable should be based on the worker�s height. That is, a short man will be more comfortable working at a height identified for a woman and a tall woman might require a higher work surface than indicated.
 
Table 1
Activity Height (for Women)        Height (for Men)
General            35� to 39�        39� to 43�
Precision Work            41� to 45�        43� to 47�
Heavy Work    31� to 37�        34� to 40�
 
Hands. There are three areas of cumulative trauma disorder (CTD) involving hands and wrists. One disorder, carpal tunnel syndrome, is a mechanical problem. The tendons to the fingers are moving back and forth through a tunnel in the wrist called the carpal tunnel. Eventually, the sheaths around the tendons swell up and compress the median nerve causing a loss of sensation in the fingers and hand. Keeping the hand in the neutral position, with the wrists straight and not bent up or down, maximizes the opening in the tunnel, thus minimizing the probability of carpal tunnel syndrome.
 
Legs and feet. When the worker stands all day long, he or she is at risk of a number of problems. Resilient tile or carpet laid on concrete is no better. Fatigue mats should be provided to prevent the jarring action of hitting the floor, support hose prevents varicose veins that result when blood pools in the lower extremities and a rail to alternately rest each foot helps prevent trauma to the lower back. Also, make sure the worker has proper footwear.
This article skims the surface of a complex subject, but you can see a lot can be accomplished through the use of common sense. If, after you have evaluated your different jobs and are still concerned about risk factors that you need help resolving, call in an outside expert for help. But do not spend money solving problems you do not have.
 
James E. Bodi, P.E., is president of Bodi Engineering, a five-member industrial engineering firm that specializes in designing warehousing and distribution centers. He can be reached at 608-271-0635 or on the Web at www.bodiengineering.com. For more information on workplace regulations, visit OSHA on the Web at www.osha.gov. The most up-to-date information on ergonomics may be found at the NIOSH site at www.cdc.gov/niosh.