One of the biggest challenges EHS managers face is developing and delivering training that works. Complicating matters is the need to train executives and managers, technical staffs and line employees without talking over their heads or oversimplifying the subject matter and delivery. Curriculum has to be relevant to the tasks people do, both at and away from the job; the material has to be easily understood and used; and the presentation has to immediately capture and hold interest.
Ergonomics training can be particularly challenging because it's hard for many people to understand how to balance an individual's capabilities with the demands of the job when individuals are so different physically. But those physical differences also are the key to delivering effective ergonomics training: If you can make people feel the difference that neutral postures and adjustability make in working comfortably and efficiently, they'll understand and remember the principles. That's the premise behind this program.
When you're training diverse audiences, it's important to establish a common ground. In order to create a broad understanding of the term "ergonomics," I broke it down by allowing each member of the audience to tell me what "ergonomics" meant to them without divulging my own definition. Each audience member would shout out one term that meant "ergonomics" to him or her. Some of the most common of these were "comfort," "adjustability," "human," "tools," "workstations," "design," "ease" and "injury-free." Then I connected these words to form a sentence: "Ergonomics is ... the science that deals with the comfort of the human being by adjusting workstations, tools, product and workstation design to help create ease and an injury-free work environment." This exercise reached everyone in the class, proving that ergonomics isn't just scientific in nature and, therefore, hard to understand. Rather, it's very practical and easy. It"s an effective tool because it doesn't make people feel shallow or overwhelmed, and it starts your training session with class participation.
Class participation is more effective than lecture or demonstration in teaching ergonomics, so I developed these interactive exercises for beginners who need to understand the basics of ergonomics. Encourage participation by keeping the pace brisk, rewarding good answers with an ergonomic giveaway, praise or snacks, having fun, and encouraging laughter. The results will be memorable.
Exercise 1: Head and Neck (Hidden Lifting Task): Equipment: A 10- to 15-pound bowling ball (the same weight as a head) secured on a conduit or metal pipe. The goal: To simulate the weight of the head in flexion (i.e., lateral, lateral rotation and extension) and what happens to the neck in a static, at-risk position.
Select a volunteer who is wearing safety shoes. Have him hold the metal pipe in a neutral (vertical) position, then slowly tilt the ball forward at an angle. Ask him to describe to the class what he felt in his forearms and wrists when holding the ball in the neutral position and how he felt as the weight of the ball shifted to a forward angle. Call particular attention to the muscles in the forearms during this exercise, and discuss how the same strain occurs in the neck and trapezius muscles.
Exercise 2: Shoulders: Equipment: Four- to 5-foot lengths of gray-strength TheraBands or elastic rubber material. The goal: To simulate activities involving reaching forward, backward, across and upward, as well as those that cause people to work with shoulders and elbows raised. It's very effective for convincing nonbelievers of the reality of cumulative trauma disorders (CTDs).
Start by warning participants that some activities may cause pain, and they are to stop at the first sign of discomfort. Tell them to place one end of the TheraBand securely under their feet. Then, with elbows close to their bodies, perform a biceps curl and hold the position. Call attention to the way stress is equally divided among their arms, shoulders, backs and necks.
Have them again stand on one end of the elastic material and perform the biceps curl-and-hold with their elbows held outward from the body in the "chicken wings" position. Also use the elastic material to simulate a person in full reach to the front, side or behind the shoulder line. Discuss the differences in the way they feel in these positions.
Exercise 3: Wrists and Hands: Equipment: Pencils. The goal: To simulate the effects of ulnar deviation and flexion on grip strength. (It's also great for nonbelievers in CTDs.)
To simulate ulnar deviation (and DeQuervain's Disease), tell participants to touch the thumb of one hand to the palm, make a fist, and bend the wrist in the direction of the little finger. Ask them to discuss the pain they feel shooting up their forearms and relate it to jobs in their environment that may have the same postural effect.
Next, demonstrate the effect of flexion on grip strength by dividing the class into partners and having one partner grasp a pencil in one fist. and hold it as tightly as possible, keeping the wrist straight (i.e., in neutral position). Have the other partner attempt to pull the pencil from their grip. Now try the same activity, but with the wrist bent forward (i.e., flexion). The pencil should be easier to remove because, at a 45-degree angle of flexion, the hand's grip strength is reduced to approximately 60 percent of its full capacity.
Repeat the process so all participants understand the effects of ulnar deviation and flexion.
Exercise 4: Forearms: The goal: To understand how working with the forearm and palm upward (i.e., supination) causes fatigue.
Tell participants to turn their forearms upward and form their hands into fists. Have them open and close their fists quickly until their forearms start to feel fatigued. When that happens, tell them to continue opening and closing their fists, but to turn the palms to face the neutral position. Call attention to how quickly the arms tire when working in a risky position.
Exercise 5: Lower Back/Torso: The goal: To explain why the S curve in the lower back must remain curved during strenuous activities or lifts.
Have participants place one fist in the lower curve of their backs with the knuckles against the spine, then bend forward until they feel the spine force the fist out of the curve of the lower back. Explain that, when the lower spine is straight, the spine is subjected to additional stress, placing the lower back at risk for injury.
Then have participants stand straight in the same position. Tell them to bend at the knees, instead of the waist, and notice how the curve remains in the lower back. Explain the mechanics of proper lifting with the legs, not the back.
Ask participants to show how they get groceries out of the car trunk without straining the back by bending at the waist. Ask them whether paper or plastic bags are better at aiding this task (plastic bags have handles). Explain how putting one foot forward with the knee against the bumper increases stability. Tip: Any example that brings a person's home life into the work training setting builds interest.
Exercise 6: Lower Back/Torso: The goal: To demonstrate how standing with one foot forward and the knees slightly bent improves balance and relieves fatigue.
Divide the class into pairs. Have one partner stand with feet together, knees straight, arms straight forward and hands clasped in front of the chest. The other partner faces her and pushes down on her hands as she resists the downward pressure. (Be careful; students may fall forward!) Then repeat the exercise, but, this time, with one foot forward and her knees slightly bent. Call attention to how the second posture helped her maintain balance and gain better footing. Then switch roles. This exercise is effective in teaching assembly workers how to stand to gain better balance. It also explains how propping one foot on a box or rail relieves back and leg fatigue in standing jobs.
To explain the mechanics of jobs involving twisting, have students stand straight and twist at the waist without pivoting the feet. Then have them twist after assuming the "batter's stance": knees slightly bent, weight on the balls of the feet. To minimize the risk of back injury from twisting, use the rhyme, "Nose follows toes to minimize the woes."
Exercise 7: Static Positions and Weight Distribution: Equipment: A ream of copier paper. The goal: To understand grip strength and the proper way to carry loads.
Have a participant grip a ream of copier paper in one hand with the paper below the hand and hold it in front of himself and as close to his body as possible without touching it for 20 or more seconds. Ask him to guess how heavy the ream of paper is.
Then have him hold the paper with his arm half-extended, and ask again how heavy the paper is.
Repeat with the arm fully extended and ask again how heavy the load feels at this posture.
Explain the proper way to carry loads close to the body, and explain how grip strength is lost when static positions are maintained for 15 to 20 seconds and the hands begin to shake and burn.
Exercise 8: Other Exercises: Equipment: A hand dynamometer.
A. Wrist flexion/extension: The goal: To explain how a power grip is affected by flexion and extension. Have a volunteer stand with one arm extended and the dynamometer in hand. Her little finger should be parallel with the ground (i.e., neutral posture). Have the person squeeze the dynamometer as hard as possible, and announce the reading to the class. Next, have her flex her wrist downward (flexion) while squeezing, and announce the reading. Finally, repeat the exercise with the wrist flexed toward the ceiling (extension). Discuss the reason grip strength is dramatically reduced by working with the wrists out of neutral posture.
B. Reach envelope: The goal: To demonstrate why adjustability is important. From the class, select three people of different heights and gender and have them stand in a line facing the class. Have them extend their arms toward the ceiling so students can see the differences in their reach envelopes.
Next, have them turn to the side and reach forward at shoulder height so the differences in reach are clear.
C. Ergonomics in design: Equipment: Assemble ergo kits of small, inexpensive personal, household or work items that demonstrate adjustability, ambidexterity and multipurpose qualities, and include both old and new items for comparison. Kitchen gadgets and items from hardware and office supply stores that manufacturers have labelled "ergonomic" are easy to find.
Have each participant take an item from the kit and explain what the item is and how its design addresses the ergonomic principles presented in class. When possible, compare old and new designs of an item (e.g., potato peeler, razor, pen). This is a particularly effective exercise for engineering audiences so they understand ergonomics in design. It also helps participants define ergonomics by what they observe in the design of the items.
If ergonomic protective apparel, such as a wrist immobilizer, is used by your work force, wear one the wrong way to demonstrate how not to use it. Then show how to use it correctly, and let the group comment on the differences.
You can combine any of a number of materials with this training guide to create a more advanced presentation on ergonomics. The principle of these exercises is to use common household and office items and techniques in hands-on demonstrations to help people understand the differences between neutral, "ergonomically correct" postures and risky ones. Start with these exercises and add your own demonstrations of the effects of repetition, force, duration and other factors that increase the risk of injury. But I warn you: These exercises can cause excitement and laughter -- and a better understanding of ergonomics!
James Allsopp is global program manager, New Product Introduction & Ergonomics, for G.E. Appliances' global EHS operations, headquartered in Louisville, Ky. He is a board member of the Kentucky Safety and Health Network and is on the organizing committee for the annual Applied Ergonomics Conference sponsored by OSHA, IIE, NIOSH and ASSE. Allsopp has worked for NIEHS as a contracted instructor. His B.S. and M.S. in safety engineering are from Murray State University, with an emphasis in industrial hygiene.