Work-related ergonomic risk factors are the physical stressors and workplace conditions that may pose a risk of injury to the musculoskeletal system of an employee. Because these factors occur during work performance or during interaction of an employee with the work environment, they are referred to as work-related ergonomic risk factors. The following activities are recognized as important risk factors, especially when performed frequently and/or in combination with each other:
Performing the same constant actions can result in fatigue and strain of muscles and tendons, especially when performed frequently over a prolonged period of time. Overused, tired muscles and tendons cannot recover from the effects of repeated actions if sufficient recovery time is not allotted between exertions. For most repetitive strain injuries, the disease progresses through three injury/disease stages. The effects of performing repetitive actions are increased when combined with awkward postures and forceful exertions.
- Intensive data entry requiring rapid, repeated keying actions
- Manual material-handling activities
Working in stressful or non-neutral body postures can fatigue or stress affected parts of the body due to the amount of force or stress which occurs.
- Working with bent or flexed wrists
- Performing tasks with outstretched arms
- Prolonged holding of a single posture or position
- Lifting, lowering, or handling objects when the back is bent or twisted
- Sudden, jerking movements made during the work process
- Frequent or prolonged extended reaching for materials, especially above the shoulders
- Frequent stooping or squatting
Forceful Exertions (Including Lifting, Pushing and Pulling)
Placing excessive loads on the muscles, tendons, ligaments and joints increases demands on the body necessary to sustain an increased effort, such as greater muscle exertion and physiological changes.
- Using small or narrow tool handles that lessen grip capacity
- Using the index finger and thumb in a pinch grip to forcefully grip objects
- Twisting, bending or stooping at the waist to lift and lower loads
- Lifting, loading or lowering objects that do not have adequate hand-holds
Placing the forearms, wrists or fingers in repeated or continual contact with hard or sharp objects/surfaces or with unpadded, narrow tool handles can interfere with proper nerve function and blood flow.
- Pressing forearms or wrists against sharp/hard desk edges when keying or writing
- Using tools that press into the base of the palm
- Using the palm of the hand as a hammer
Localized vibration exposure is produced by contact between the hands and a vibrating object, such as a power tool. Whole-body vibration exposure occurs while standing or sitting in vibrating environments such as in trucks or heavy machinery, or while using heavy equipment such as jackhammers.