Focusing on Exposure Control for Safer Workplaces

Keeping people safe at work starts with one core principle: reduce or remove exposure to hazards whenever possible. To guide organizations in doing this consistently, safety professionals rely on the Hierarchy of Controls—a structured approach that ranks risk-reduction strategies from most effective to least effective. 

Although all levels of the hierarchy play a role, the true power lies in understanding how each step contributes to exposure control—the process of minimizing the amount, duration, or intensity of a worker’s contact with a hazard.

1. Elimination – Remove the Hazard Entirely

Most effective

Elimination means physically removing the hazard, ensuring zero exposure. If a dangerous

chemical isn’t used, or a task requiring work at heights is redesigned to be performed at ground level, the hazard no longer exists—and exposure control becomes effortless.

Examples:

• Designing out the need for confined space entry
• Switching to a non-hazardous material
• Fully automating a task so workers are no longer present in the danger zone

Exposure impact:

Elimination is the gold standard because it completely removes the possibility of exposure.

2. Substitution – Replace the Hazard with Something Safer

Highly effective

When elimination isn’t feasible, substitution can significantly reduce exposure by replacing the hazard with a less dangerous alternative.

Examples:

• Using a water-based adhesive instead of a solvent-based one
• Replacing old equipment with low-noise or low-vibration models
• Using safer cleaning chemicals

Exposure impact:

Substitution works by reducing exposure intensity—making the hazard inherently less harmful.

3. Engineering Controls – Isolate People from the Hazard

Very effective and highly reliable

Engineering controls create a physical barrier between workers and hazards. Instead of relying on human behaviour, these controls change the work environment itself.

Examples:

• Local exhaust ventilation (LEV) to capture airborne contaminants at the source
• Machine guarding and interlocks
• Sound enclosures around noisy machines
• Negative-pressure rooms for infectious agent isolation

Exposure impact:

Engineering controls directly limit the amount of hazard reaching the worker, making them a cornerstone of exposure control strategies.

4. Administrative Controls – Change the Way People Work

Moderate effectiveness

Administrative controls reduce exposure by altering how work is organized. They don’t remove the hazard, but they minimize contact or reduce exposure duration.

Examples:

• Rotating workers to limit time near a hazardous area
• Scheduling high-exposure tasks when fewer people are present
• Creating safe work procedures or lockout/tagout (LOTO) programs
• Providing training and signage

Exposure impact:

These controls limit exposure frequency and duration but rely heavily on adherence and training.

5. Personal Protective Equipment (PPE) – Protect the Worker, Not the Workplace

Least effective but still essential

PPE acts as the last line of defence when hazards cannot be removed or controlled by other means. While critical, PPE’s effectiveness depends on proper selection, fit, training, and maintenance.

Examples:

• Respirators
• Gloves
• Eye and face protection
• Hearing protection
• Protective clothing

Exposure impact:

PPE reduces hazard contact but does not eliminate exposure—and failure rates can increase due to human factors.

Exposure Control: The Common Thread

Across the hierarchy, the ultimate goal is the same: reduce exposure to hazards so workers stay

safe. 

Here’s how each level aligns with exposure control:

• Elimination: Eliminates exposure completely
• Substitution: Reduces exposure intensity
• Engineering controls: Block or capture hazards before workers are exposed
• Administrative controls: Limit time and situations of exposure
• PPE: Provides a barrier when exposure cannot be otherwise controlled

The most effective exposure control programs layer multiple control types—often combining

engineering controls with administrative strategies and PPE as backup.

Putting the Hierarchy Into Practice

To apply the hierarchy effectively:

1. Assess hazards thoroughly (air monitoring, noise surveys, job hazard analyses).
2. Prioritize controls at the top of the hierarchy whenever feasible.
3. Design layered protection, not single solutions.
4. Regularly review controls for effectiveness and opportunities to upgrade.
5. Engage workers—their feedback is crucial for identifying real-world exposure issues.

Final Thoughts

The Hierarchy of Controls is more than a theory—it’s a roadmap to smarter, more effective exposure control. By focusing on reducing exposure at the source, organizations can create safer environments, protect worker health, and build a culture where safety is engineered into every task.