In today’s modern laboratory, it’s just a fact that you are going to spend some time on a computer and perform other repetitive actions. Do you have grant or budget information or data to enter into spreadsheets? Do you have a stack of standard operating procedures, a chemical hygiene plan, or chemical inventory documents to review and update? Do you seem to get three emails for every one you send? Tasks such as these may mean hours and hours glued to your keyboard and mouse. Have you noticed lately that you hurt after just a few minutes at the computer? Once you get home, have you noticed a pain in your shoulder or neck, or perhaps you wake up at night with tingling in your wrist or hand? If so, read on to learn about ergonomics and what you can do to minimize potential ill effects.
Stated simply, ergonomics is the study of how we interact physically with our work environment to perform required tasks. Ergonomic conditions can affect those working in all types of laboratories. The “office” aspect of laboratory research should not be overlooked, and that will be our focus in this month’s Safety Guys article. Increasingly, our jobs require a substantial portion of the day working with a computer. Too often we hear complaints of pain and discomfort experienced at work or at home that could be tied to ergonomic risk factors. Poor ergonomic conditions and practices result in potential economic, workers’ compensation, and productivity losses due to employee suffering and lost time.1 Fortunately, these are easily recognized and corrected.
The Occupational Safety and Health Administration (OSHA) provides an excellent review and recommendations through its eTool on ergonomics.2 The three fundamental ergonomic risk factors are: posture/position, repetition/duration, and force. The work area setup as well as the activity being performed are influenced by these factors. The good news is these risk conditions with the potential to cause pain and injury are easily controlled if one understands basic ergonomic concepts and how to apply them. In this article, we will look at the first of these factors, posture and position, and provide some practical solutions to help get you through the day pain free.
Posture and position
The goal for proper posture is to achieve a balanced and neutral position. “Neutral” is typically thought of as the midpoint of range of motion for most joints. For example, your wrists nearly straight in both the up-and-down and side-to-side axes, your upper arm hanging comfortably from the shoulder, and your back and neck straight and not twisted or bent. “Balanced” in the ergonomic sense is when a posture or position is one that minimizes the fight against gravity to maintain that posture or position.
Some of the most common position-related complaints we see stem from neck and/or shoulder pain. The average person’s head weighs about ten to 12 pounds—think of a bowling ball. Holding a bowling ball upright while resting your elbow on a table takes effort. Now, visualize balancing a bowling ball (your head) on a cylinder (your neck). When you sit upright and are looking directly ahead, your skeletal structure supports most of the weight; if you deviate from a vertical position, your muscles must come increasingly into play to support your head. Now, imagine tipping and lifting that bowling ball hundreds of times a day—that is exactly what you are doing when working at a computer, looking up and down from desk to monitor and back. Your head moves up and down and side to side each time you look down and then up to the computer screen. Similarly, if your monitor is placed on the CPU so that you must tip your head back to read (particularly problematic for those wearing bifocals), your muscles must support this off-balance posture. A much better approach is to place your hardcopy on a document stand between the keyboard and monitor. The monitor should be directly in front of you with the top of the screen just at or slightly below eye level. This way, instead of repetitive up-and-down and side-to-side head motion, you can look back and forth between paper and screen almost by using your eyes alone, allowing you to remain in a neutral, balanced position.
Another very common bad habit we see is holding the telephone receiver cradled between your ear and shoulder while doing other tasks. This is also a classic cause of neck pain if done on a regular basis. Hold the receiver in your hand if possible. Or use a speakerphone or headset if you must speak on the phone while working, such as when reviewing written materials or computer files.
Try this exercise: Hold your arm straight out in front of you for a couple of minutes. Now, try drawing your shoulders up a couple of inches toward your ears and hold them there for a minute or two. Did you begin to feel discomfort and fatigue relatively quickly? This illustrates stresses from an ergonomic standpoint that can occur when one is working with a keyboard or mouse on a surface that is too high or too far away. For example, have you seen coworkers using a keyboard or mouse on top of a standard-height desk or using an older keyboard tray that doesn’t have room for the mouse? If so, this necessitates that you reach over the edge and out to use the input devices. Although usually not an issue for tall individuals, it is problematic for most average and shorter people. Ideally, when using a keyboard or mouse your upper arms should hang comfortably at your side. The approach we most often take in a case such as this is to recommend installation of a combination keyboard/ mouse tray.
The mouse pad or surface is best on the same plane as the keyboard, and even better when it can rotate over the keyboard or move toward you to reduce your reach and allow you to keep your elbows in while working. The keyboard platform is best kept level or sloped slightly downward (toward your thighs) so that your wrists are straight (neutral) while typing.
We have started to explore the ergonomic risk factors associated with the use of computers, a very common task in the modern laboratory. The take-home message in this column is “balanced” and “neutral.” Keep your monitor directly in front of you with the upper edge at eye level or slightly below. Place hardcopies in front of you on a document stand either between the keyboard and monitor or immediately to the side of the monitor. Keep the keyboard and mouse in front of you and as close as practical to prevent overreaching. Make sure your wrists are as straight as possible in both axes. In addition to the OSHA eTool, the state of Washington has some very good self-evaluation checklists and online training guides to help you identify and correct many posture and position pitfalls.3
1. Prevention of Musculoskeletal Disorders in the Workplace, US Department of Labor, Occupational Safety and Health Administration. Washington, D.C. https://www.osha.gov/SLTC/ergonomics/
2. Computer Workstations, US Department of Labor, Occupational Safety and Health Administration. Washington, D.C. http://www.osha.gov/SLTC/etools/computerworkstations/index.html
3. Office Ergonomics, Washington State Department of Labor and Industries. Tumwater, WA. http://www.lni.wa.gov/Safety/TrainingPrevention/workshops/WorkshopInfo.asp?WkshopID=53#description