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.