What is the hierarchy of controls, and how should it be applied?

This article explains the hierarchy of controls, a framework for reducing workplace hazards by prioritising elimination, substitution, and engineering controls over administrative measures and PPE.

The hierarchy of controls is an essential framework in occupational health and safety (OHS) designed to effectively reduce or eliminate exposure to workplace hazards. This framework provides organisations with a clear roadmap for safeguarding their employees against potential risks. By ranking control measures based on their effectiveness, the hierarchy highlights the most impactful methods at the top and the least effective ones at the bottom.

Central to this approach is the focus on tackling hazards at their source rather than depending solely on individual behaviour or protective equipment. By adopting this organised strategy, organisations can significantly improve workplace safety while also implementing long-term and effective risk-reduction measures. This proactive approach not only ensures worker protection but can also enhance productivity and boost morale, as employees feel more secure and appreciated in their work environment. Furthermore, embracing the hierarchy of controls cultivates a safety-oriented culture within the organisation, promoting ongoing improvement and vigilance in managing hazards.

The Hierarchy of Controls Explained

1. Elimination

   • Definition: Removing the hazard entirely from the workplace, eliminating any associated risks.
   • Example: Replacing manual heavy lifting tasks with automated machinery.
   • Effectiveness: Most effective as it removes the hazard completely, but often challenging due to feasibility or cost.

2. Substitution

   • Definition: Replacing a hazardous material, process, or activity with a safer alternative.
   • Example: Using water-based paint instead of solvent-based paint to reduce exposure to toxic fumes.
   • Effectiveness: Highly effective but requires careful consideration to ensure the substitute does not introduce new risks.

3. Engineering Controls

   • Definition: Physically isolating people from the hazard or altering the work environment.
   • Example: Installing guards on machinery or adding ventilation systems.
   • Effectiveness: Reduces risk at the source and does not rely on worker behaviour, making it more reliable than administrative controls or PPE.

4. Administrative Controls

   • Definition: Implementing policies, procedures, or training to reduce exposure to hazards.
   • Example: Rotating workers to minimise repetitive strain injuries or conducting safety training programs.
   • Effectiveness: Relies on consistent adherence by workers, making it less effective than elimination or engineering controls.

5. Personal Protective Equipment (PPE)

   • Definition: Providing workers with protective gear to reduce exposure to hazards.
   • Example: Hard hats, gloves, eye protection, or respiratory masks.
   • Effectiveness: Least effective as it depends entirely on proper use and maintenance by workers. Should be used as a last line of defense.

How to Apply the Hierarchy of Controls

1. Assess the Hazard

   • Identify and evaluate the nature, likelihood, and severity of the hazard.
   • Use risk assessments to prioritise hazards that require immediate action.

2. Select Control Measures

   • Start at the top of the hierarchy (elimination) and work downwards.
   • Consider combining controls for more comprehensive risk reduction (e.g., engineering controls with administrative measures).

3. Implement Controls

   • Ensure proper installation or enactment of the chosen measures.
   • Provide training and support for new processes or equipment.

4. Monitor Effectiveness

   • Regularly inspect and test controls to ensure they remain effective.
   • Gather feedback from workers to identify potential gaps or unintended consequences.

5. Review and Adapt

   • Update controls in response to new hazards, operational changes, or incidents.
   • Continuously seek opportunities to move higher in the hierarchy.

Practical Application Examples

• Noise Control:

  • Elimination: Cease operations causing excessive noise.
  • Substitution: Use quieter machinery.
  • Engineering Controls: Install soundproof enclosures.
  • Administrative Controls: Limit time spent in high-noise areas.
  • PPE: Provide hearing protection devices.

• Chemical Hazards:

  • Elimination: Discontinue use of harmful chemicals.
  • Substitution: Use non-toxic alternatives.
  • Engineering Controls: Install fume hoods.
  • Administrative Controls: Establish protocols for safe handling.
  • PPE: Provide gloves and respirators.

Summary

The hierarchy of controls is a systematic approach to reducing workplace hazards.

The hierarchy prioritises elimination, substitution, and engineering controls ahead of administrative measures and personal protective equipment (PPE). This organised framework not only assists organisations in effectively managing risks but also highlights the critical importance of addressing hazards directly at their source. By methodically navigating through the hierarchy, businesses can pinpoint the most effective strategies for risk reduction, leading to sustainable solutions that are less dependent on individual behaviours.

At the top of this hierarchy, elimination emphasises the vital goal of achieving a hazard-free environment whenever feasible. Substitution motivates organisations to explore safer alternatives, which, in turn, encourages innovation and ongoing enhancements in work processes. Engineering controls contribute to safety by establishing physical barriers between workers and potential hazards, thereby significantly diminishing exposure risks.

While administrative controls and PPE are crucial elements of a comprehensive safety program, they function as supplementary measures to be employed only after higher-level controls have been thoroughly evaluated. This methodology not only fosters a culture of safety within the workplace but also empowers employees by actively involving them in the identification and mitigation of risks.

Implementing this hierarchy enables organisations to prioritise sustainable solutions that align with occupational health and safety regulations while simultaneously boosting overall productivity and employee morale. A safer work environment leads to reduced absenteeism, lower healthcare costs, and heightened job satisfaction, resulting in a mutually beneficial situation for both employers and employees. Consequently, adopting the hierarchy of controls transcends mere regulatory compliance; it represents a strategic commitment to cultivating a resilient and safety-focused workplace culture.