Ergonomics, when properly considered and implemented, should enhance your ability to complete your Job Function safely and effectively. We routinely hear about the mental and emotional stress-ors, but our Jobs also have physical stressors. While these cannot all be eliminated, you have to be aware of the six motions (or move-ments) that contribute to potential ergonomic hazards.
1. Bending
2. Lifting
3. Pushing
4. Pulling
5. Reaching
6. Static or Sustained Postures
Bending & Twisting
Bending and twisting are a part of everyday life. However, when they are combined with other activities, bending and twisting cre-ates forces that are more likely to impact the back and spine. Most notable among the activities that bending and twisting make worse are distant lifting and lowering, pushing or pulling, and distant reaching. Three specific considerations should be made with bend-ing and twisting:
1. Bending and twisting of the spine can predispose your discs to rupture by reducing the load tolerance of the intervertebral discs.6
2. You are at a greater risk for injury with bending and twisting, be-cause of the velocity and acceleration these movements create increase the compressive and shear forces of your intervertebral discs.7
3. When lifting, while twisting or bending, it is recommended that the weight of the load be reduced by 22% from your maximum acceptable weight of lift.8
Bending and twisting will happen, but when they happen with lift-ing, pushing, pulling, and reaching you set yourself up for injury. Consider the use of assistive devices, turning your body, or the as-sistance of a co-worker to reduce the likelihood of injury.
Lifting
Lifting and lowering is one of the most vulnerable activities any em-ployee can engage in. Loads can be heavy, objects can be awk-wardly shaped, and you may not be educated on proper lifting techniques. When it comes to lifting and lowering, you should al-ways ask your self:
1. Is this less than my maximum acceptable weight of lift?
2. Is there an assistive device (like a cart, dolly, or hand truck) availa-ble?
3. Is there someone (trained in lifting) who can help me?
4. Do I have a clear path?
If the answer to any of these questions is “No,” consider whether this task is worth the possible injury.
Pushing & Pulling
Pushing and Pulling, while not exactly the same, have many of the same risks due to the nature of the tasks. Oftentimes, when pushing or pulling, you are dealing with a heavier load. In the case of push-ing or pulling, assuming the load is not beyond your ability, your posture should be your number one priority. When it comes to pushing and pulling, you should always ask your self:
1. Is this less than my maximum acceptable weight?
2. Am I able to maintain an upright posture while pushing or pull-ing?
3. Can my hands remain above my waist while moving this object?
4. Can I control this cart safely?
If the answer to any of these questions is “No,” consider how you can modify the activity to minimize the risk of injury.
Reaching
Reaching can be broken into two types:
1. Horizontal Reach — long reaches away from and in front of the body.
2. Vertical Reach — reaches above the knees and below the shoulders.
Both types of reaching put you at risk for injury because of the movement of the load away from your center of mass. This reduces the amount of weight you can carry, and this reduces your ability to maintain a safe weight for a prolonged period (try holding a milk jug out at arms reach and you will understand).
Static or Sustained Postures
Remaining in the same place or the same posture for an extended period puts increased pressure on the joints of the feet, ankles knees, hips, back, and neck. When it comes to workstation fit, three common postural positions can increase the likelihood of pain or in-jury:
1. Sitting for a prolonged period, espe-cially when they don’t provide prop-er lumbar support or the chair is im-properly sized.
2. Your workstation surfaces are too high or too low for comfortable completion of the task.
3. Standing on a hard surface for an extended period without support or proper cushioning.