Ergonomics Flashcards
What are WMSDs?
Work-Related Musculo-Skeletal Disorders, aka
- cumulative trauma disorders (CTDs)
- Repetitive strain injuries (RSIs)
- Overuse injuries
they are generally soft-tissue injuries that occur gradually
what are some symptoms of WMSDs?
- discomfort
- pain
- numbness, tingling
- burning
- swelling
- change in color
- tightness, loss of flexibility
what causes WMSDs?
- Hand intensive work
- forceful exertion - requires force exerted one hand >10lbs
- stationary/awkward positions
- segmental vibration
- lifting - frequent (>once/hour) handling >20lbs or occasional (>once/shift) handling 40lbs or more
- pushing or pulling loads that are hard (exertions greater than 40lbs) to move or stop
- awkward motions - includes one or more of the following:
- full arm reaches
- twisting or bending of the back
- wrist bent at or near max ROM
- working with one or more hands above chest height
- repetitive motions - task that is repeated 4x/min or more
what is meant by segmental vibration?
exposure to vibrating tools or work objects >2 hours continuously or over 50% of the work cycle
what is ergonomics?
the science and practice of designing jobs and workplaces to match the capabilities and limitations of the human body
it means “fitting the job to the worker”
What are the goals and benefits of ergonomics?
- Provide max productivity with minimal cost
- Maintain health and productivity of workers at an optimally safe level
- Benefits
- decrease injury rate
- improve quality of work
- improve QOL
- reduce fatigue and discomfort
list alternatives to lifting
- use carts, hand trucks, hoists, conveyors or other mechanical assistances
- slide objects instead of lifting them
- store heavy items where individual will not have to bend or reach to lift them
- use ladders to get items down from high shelves
list some ways to reduce low work
- raise and/or tilt the work for better access
- use a stool for ground level work
- use tools with longer handles
- alternate between bending kneeling, sitting, and squatting
list some ways to reduce high work
- use an elevated work platform or rolling stairs
- use tools with longer handles
- limit overhead storage to infrequently used items
- bring the work down and tilt for easier access
list some ways to reduce reaching
- keep items within close reach → design reach distance for the shortest worker
- remove obstacles
- use gravity racks
list ways to reduce repetition
- arrange work to avoid unnecessary motions
- let power tools and machinery do the work
- spread repetitive work out during the day
- take stretch pauses
- rotate task with co-workers if possible
- change hands or motions frequently
a power grip is _________ than a pinch grip
5x stronger
list ways to reduce grip force
- grip with the whole hand, not just the fingertips
- pick up smaller loads
- use carts or hand trucks instead of carrying
- keep tools in good working order
- use lighter tools or tool balancers
- use two hands
- keep your wrists straight
list ways to avoid a pinch grip
- pick objects up from the bottom using whole hand
- attach handles or use lift tools
- build up handles on small tools to reduce grip force
list ways to reduce vibration
- use low vibration tools if available
- maintain tools
- use anti-vibration gloves or tool wraps