Hierarchy of Controls: From Elimination to PPE

Table of Contents

Hierarchy of Controls: From Elimination to PPE

Workplace hazards exist in every industry, from construction and manufacturing to oil & gas and warehousing. To control these hazards effectively, safety professionals rely on a globally accepted framework known as the Hierarchy of Controls.

This method prioritizes safety measures based on their effectiveness, guiding organizations toward the safest possible solutions.

“The Hierarchy of Controls ranks hazard control methods from most effective to least effective—starting with elimination and ending with PPE.”

This article explains each level of the hierarchy, with examples and implementation strategies.

What Is the Hierarchy of Controls?

The Hierarchy of Controls is a structured approach used to control or mitigate workplace hazards. The concept is mandated in many safety standards, including:

OSHA (Occupational Safety and Health Administration)
NIOSH (National Institute for Occupational Safety and Health)
ISO 45001
HSE (UK Health and Safety Executive)

Order of Effectiveness (Top to Bottom)

Elimination
Substitution
Engineering Controls
Administrative Controls
Personal Protective Equipment (PPE)

1. Elimination (Most Effective Control)

Elimination involves completely removing the hazard so that the risk no longer exists.

Examples

Remove a toxic chemical from a process
Eliminate work at height by performing tasks at ground level
Automate manual heavy lifting
Remove unnecessary electrical equipment

Key Advantage

If the hazard no longer exists, workers cannot be harmed.

When to Use

During:

Design stage
Process planning
Equipment specification

2. Substitution

If elimination is not possible, substitute hazardous materials or processes with safer alternatives.

Examples

Replacing solvent-based paints with water-based paints
Using non-flammable chemicals instead of flammable ones
Using battery-operated tools instead of corded ones
Switching from manual cutting wheels to safer cutting tools

Benefits

Reduces hazard intensity
Improves worker health and safety

Important

Ensure the substitute does not introduce new hazards.

3. Engineering Controls

Engineering controls isolate people from the hazard by modifying equipment, processes, or the work environment.

Examples

Machine guarding
Local exhaust ventilation (LEV) for fumes
Soundproof enclosures
Interlocks and automatic shutdown systems
Fall protection systems (guardrails, platforms)
Fume hoods in laboratories

Advantages

Do not rely on worker behavior
Provide consistent protection

Limitations

Often require higher cost and maintenance.

4. Administrative Controls

Administrative controls reduce exposure by changing how people work.

Examples

Job rotation to reduce fatigue
Standard Operating Procedures (SOPs)
Safe work instructions
Permit-to-Work (PTW) systems
Safety signage and color coding
Toolbox talks
Training programs
Restricted access zones

Limitations

They require human compliance and may fail if not followed.

5. Personal Protective Equipment (Least Effective Control)

PPE is used when hazards cannot be eliminated or controlled through other methods. It acts as the last line of defense.

Examples

Helmets
Gloves
Safety glasses
Face shields
Respirators
Safety shoes
Hearing protection
High-visibility clothing

Limitations

Relies heavily on worker behavior
Needs proper training
Requires maintenance and replacement

When PPE Is Necessary

Confined space work
Hot work
Chemical handling
Electrical work
Construction sites
High-noise areas

Visual Representation of the Hierarchy (Top to Bottom)

Elimination – Remove the hazard
Substitution – Replace the hazard
Engineering Controls – Isolate people from the hazard
Administrative Controls – Change the way people work
PPE – Protect the worker

This pyramid shows that the first three levels prevent hazards at the source, while the last two rely on human behavior.

How to Apply the Hierarchy of Controls in the Workplace

Step 1: Identify the Hazard

Use inspections, risk assessments, and JSA/HIRA.

Step 2: Evaluate Possible Controls

Always attempt controls from the top of the hierarchy first.

Step 3: Implement the Selected Controls

Use a combination of controls where necessary.

Step 4: Train Workers

Ensure all stakeholders understand the controls.

Step 5: Monitor & Review

Check if the controls are effective and make adjustments.

Examples of Applying the Hierarchy of Controls

Example 1: Working at Height

Elimination: Bring work to the ground
Substitution: Use extendable tools
Engineering: Guardrails, platforms
Administrative: PTW, training
PPE: Harness, lanyard

Example 2: Chemical Exposure

Elimination: Remove hazardous chemical
Substitution: Use safer chemical
Engineering: LEV system
Administrative: SOPs, SDS training
PPE: Gloves, respirator

Common Mistakes to Avoid

Skipping directly to PPE
Not reviewing controls after incidents
Using administrative controls as primary solution
Failing to evaluate substitute hazards
Relying on warning signs alone

For official guidance on implementing the hierarchy of hazard controls in the workplace and prioritising effective risk reduction measures, visit the OSHA Hazard Prevention and Control resource, which explains how to select and apply controls from most to least effective.

Conclusion

The Hierarchy of Controls is one of the most powerful tools in occupational health and safety. It helps organizations prioritize effective risk control strategies and protect workers from injury or illness.