Occupational safety and health (OSH) is an essential component of any workplace, as it ensures the well-being and protection of employees. The Hierarchy of Controls is a widely-accepted approach to managing workplace hazards and reducing the risks associated with various tasks. In this comprehensive guide, we will delve into the Hierarchy of Controls, exploring its principles, the five levels of intervention, and practical examples that demonstrate its effectiveness in promoting occupational safety and health.

Understanding the Hierarchy of Controls

The Hierarchy of Controls is a systemic method for addressing workplace hazards by implementing various types of interventions in a specific order. This framework prioritizes the most effective means of control first and helps organizations systematically reduce the risks associated with workplace hazards. The National Institute for Occupational Safety and Health (NIOSH) recommends this method for managing risks in the workplace.

The Five Levels of the Hierarchy of Controls


Elimination is the most effective level of the Hierarchy of Controls, as it involves completely removing a hazard from the workplace. By doing so, the risk associated with the hazard is eliminated, and employees are no longer exposed to it. Examples of elimination include:

  • Redesigning a process to remove a hazardous material
  • Replacing a toxic substance with a non-toxic alternative
  • Discontinuing the use of a hazardous piece of equipment



When elimination is not feasible, the next best option is substitution, which involves replacing a hazardous material, process, or equipment with a less hazardous alternative. Substitution can significantly reduce the risk associated with a hazard. Examples of substitution include:

  • Replacing a hazardous chemical with a less toxic one
  • Using a lower-noise machine to reduce noise exposure
  • Switching to a less hazardous manufacturing process

Engineering Controls

Engineering controls involve physically modifying the work environment or equipment to reduce the risk associated with a hazard. These controls do not rely on worker behavior, making them more reliable than administrative controls or personal protective equipment (PPE). Examples of engineering controls include:

  • Installing ventilation systems to reduce air contaminants
  • Enclosing a noisy machine to reduce noise exposure
  • Designing ergonomic workstations to prevent musculoskeletal disorders

Administrative Controls

Administrative controls involve changes to work policies, procedures, or schedules to minimize workers' exposure to hazards. While these controls can be effective, they rely on worker compliance and are generally considered less reliable than engineering controls. Examples of administrative controls include:

  • Implementing a job rotation system to limit exposure to hazardous materials
  • Providing training on safe work practices
  • Establishing work-rest schedules to prevent heat stress

Personal Protective Equipment (PPE)

PPE is the least effective level of the Hierarchy of Controls, as it relies on the proper selection, use, and maintenance of equipment by workers. PPE should be used when other controls are not feasible or as a supplementary measure alongside other control methods. Examples of PPE include:

  • Safety goggles to protect against eye hazards
  • Earplugs or earmuffs for noise protection
  • Respirators to protect against airborne contaminants

Applying the Hierarchy of Controls in the Workplace

To effectively implement the Hierarchy of Controls, organizations should follow these steps:

  1. Identify hazards: Conduct a thorough assessment of the workplace to identify all potential hazards.
  2. Evaluate risks: Assess the severity and likelihood of each hazard, prioritizing those that pose the greatest risk.
  3. Select control measures: Determine the most appropriate control measures based on the Hierarchy of Controls, starting with elimination and working downward.
  4. Implement controls: Put the selected control measures in place and ensure that they are properly maintained and used by employees.
  5. Monitor and review: Regularly evaluate the effectiveness of the control measures in reducing hazards, making adjustments as needed to improve workplace safety.

Benefits of Implementing the Hierarchy of Controls

Adopting the Hierarchy of Controls in the workplace offers several benefits, including:

  • Enhanced safety and health: By systematically addressing hazards and implementing effective control measures, organizations can significantly reduce the risk of accidents and occupational illnesses.
  • Legal compliance: Employers have a legal obligation to provide a safe work environment. The Hierarchy of Controls helps organizations comply with OSH regulations and guidelines.
  • Improved productivity: A safer work environment leads to fewer accidents, reduced absenteeism, and increased employee morale, which in turn can boost productivity.
  • Cost savings: Reducing workplace hazards can lower workers' compensation costs, medical expenses, and potential legal liabilities.
  • Reputation management: A strong safety record can enhance an organization's reputation among customers, investors, and potential employees.

Real-world Examples of the Hierarchy of Controls in Action

Manufacturing Industry: A metal fabrication company identified excessive noise exposure as a hazard for its workers. To address the issue, the company first tried eliminating the noise source but found it impractical. They then substituted the noisy machinery with quieter alternatives and added engineering controls such as sound barriers and absorptive materials to further reduce noise levels. Workers were also provided with earplugs as PPE.
Construction Industry: A construction company recognized the risk of falls from heights as a significant hazard. They first attempted to eliminate the need for work at heights by modifying the building design. When this was not possible, they implemented engineering controls, such as guardrails and fall arrest systems. In addition, workers were provided with appropriate PPE, such as harnesses, and received training on fall prevention measures.
Healthcare Industry: Healthcare workers face numerous hazards, including exposure to infectious agents. To minimize the risk, a hospital implemented engineering controls, such as installing negative pressure isolation rooms and implementing proper ventilation systems. Administrative controls, like proper hand hygiene protocols and training on infection control practices, were also put in place. Lastly, healthcare workers were provided with PPE, such as gloves, masks, and gowns, to minimize the risk of exposure.


The Hierarchy of Controls is a proven and effective approach to managing workplace hazards and improving occupational safety and health. By systematically addressing hazards and implementing control measures in a prioritized order, organizations can significantly reduce risks, ensure compliance with regulations, and create a safer work environment for their employees. Regular monitoring and review of implemented controls will ensure ongoing effectiveness and help maintain a strong safety culture in the workplace.