Manual Task Concepts and MSD Risk Management

Manual Task Concepts and Mechanisms of Injury

Key Concepts

• Manual Tasks vs. Hazardous Manual Tasks:

• Manual tasks: Any task that uses the body to move or hold objects (e.g., lifting, stacking, sorting).

• Hazardous manual tasks: Tasks with risk factors that can lead to musculoskeletal disorders (MSDs).

• Musculoskeletal Disorders (MSDs):

• Defined as injuries or diseases affecting the musculoskeletal system, occurring suddenly or cumulatively over time.

• Includes sprains, strains, nerve injuries, and degeneration, but excludes crushing or cutting injuries.

Importance of Risk Management

• MSDs account for around 30% of workers' compensation claims in Australia, emphasizing the need for effective risk management strategies.
• Safe Work Australia has established codes of practice to manage risks associated with hazardous manual tasks.

Definition of Hazardous Manual Tasks

• Hazardous manual tasks involve:
• Lifting, lowering, pushing, pulling, or moving objects that:
  • Require repetitive or sustained force.
  • Involve high or sudden force.
  • Require repetitive movement.
  • Demand sustained or awkward posture.
  • Include exposure to vibration.

Overview of MSDs and Their Causes

• Common injuries include lower back and upper limb disorders that arise from:
• Gradual wear and tear or sudden damage to the body.
• Increased muscle tension and fatigue, especially from awkward postures or repetitive actions.
• Occupational exposure to high-risk activities increases the likelihood of MSDs, particularly when combined with psychosocial factors, such as job stress or workplace relationships.

Mechanisms of Injury

• Common mechanisms include:
• Muscles contracting beyond their strength.
• Joints being forced beyond their normal range of movement.
• Sustained postures that compress tissues and restrict blood supply.
• Poor ergonomics that do not consider individual differences in height or strength.

Identifying and Assisting MSD Risks

• Risk assessment involves:
• Reviewing task observations and personal accounts of discomfort.
• Consulting with workers to identify risk factors in their activities.
• Utilizing developed codes of practice for legal compliance and hazard identification.

Workplace Risk Management Strategies

• Successful strategies include:
• Encouraging worker participation in identifying risks.
• Using ergonomic assessments to design safer workplaces.
• Implementing training sessions on safe manual handling practices.

Tools for Risk Assessment

• Various tools can assist in conducting risk assessments for manual tasks:
• REBA (Rapid Entire Body Assessment) evaluates body postures and predicts injury risk.
• NIOSH Lifting Equation provides guidelines for safe lifting practices based on load and body mechanics.
• Tools like Michigan 3D Strength Prediction Program model the effects of different lifting tasks on human anatomy and provide insights into safe engagement during manual work.

Relationship with Psychosocial Factors

• Exposure to psychosocial risks can compound physical risks, leading to increased incidences of MSDs. Key factors include:
• Job dissatisfaction, intense workloads, inadequate rest breaks, and poor support from management.
• Understanding the link between psychosocial and physical hazards is essential for effective risk management and the overall reduction of MSD incidents.

Conclusion

• Proactive approaches to identifying, assessing, and managing risks related to manual tasks are essential for minimizing the impact of MSDs in the workplace.
• Employers should adopt a comprehensive risk management framework that includes both physical and psychosocial aspects to create a safer work environment.