Class 4 Flashcards
(18 cards)
What is the goal of the step 3 in the ergonomic process: implement controls?
Reduce exposure to task-related risk factors
What is the hierarchy of controls from most effective to least
1-. Elimination
2-. Substitution
3-. Engineering controls
4-. Administrative controls
5-. PPE
What are engineering controls? and state an example
change the task or environment itself, for example adjusting workplace design to improve posture, use lift assist devices or power tools to reduce forceful exertions.
What are administrative controls? and state an example
change exposure to the task or environment, some examples are rest breaks, job rotations, job enlargement and stretching programs
What defines a neutral posture?
Is when joint angles are near the middle of their range of motion, minimizing stress and reducing muscle effort.
What defines an awkward posture?
requires excessive muscle effort to work against gravity due to joint angles that deviate significantly from neutral.
What defines an extreme posture?
Occurs when a joint is near its limits of motion, which can significantly increase muscle effort and stress on tissue.
why are awkward or extreme postures problematic in the workplace?
they demand increase muscle effort, resulting in higher force and stress on joints and tissues, leading to fatigue- a major risk factor for WMSDs
How should job tasks involving awkward or extreme postures be analyzed?
by determining the frequency, duration, and magnitude of these postures using validated job analysis tools to identify potential risks.
what are high force exertions and their effects?
High force exertions involve significant muscle effort that can cause muscle fatigue, stress on joints, reduced circulation, and excessive tissue strain, increasing injury risk
Examples of tasks that involve high force exertions?
- Lifting
- carrying
- pushing
- pulling
- gripping
- pinching
especially common in manual material handling (MMH)
what factors should be measured in a job analysis for high force tasks?
the weight of objects, friction forces, frequency and duration of exertions, and the magnitude of the force required are key factors to assess.
what are some controls use to reduce high force exertions?
- enhance or reduce friction where appropriate
- pick up fewer objects at a time
- select lighter tools
- employing hoists or conveyors
- adding supportive work surfaces or fixtures.
what does repetition in work tasks refer to ?
repetition is the frequency with which a task or movement is performed continuously, which can lead to overuse injuries when combined with other risk factors.
what is contact mechanical stress and why is it important ?
is the stress applied directly to tissues (such as blood vessels and nerves) through mechanical contact. It can reduce blood flow and contribute to fatigue and injury.
How do temperature and vibration serve as task related risk factors ?
cold temperatures can reduce circulation, increasing injury risk, while hot environments can lead to quicker fatigue. Vibration can decrease circulation, reduce sensory feedback, and unconsciously increase force exertions.
what are some persistent challenges in preventing WMSDs?
challenges include the unclear relationship between exposure levels and injury risk, individual variability in injury development, complex interrelationship among risk factors, and conflict between reducing risk and maintaining productivity.
