Which statement about the top tier of the Hierarchy is correct?

• A. PPE is the top tier
• B. Warnings is the top tier
• C. Elimination or Substitution is the top tier
• D. Engineering Controls is the top tier

Answer: (C)

At the highest level of the Hierarchy of Controls, the aim is to remove the hazard from the workplace or substitute it with a less hazardous option. This stops exposure at the source, so workers aren’t exposed at all, which makes it the most effective form of protection. If you can eliminate the hazard or replace it with something safer, you don’t rely on workers to use equipment correctly or on complex systems to function properly. Only when removal or substitution isn’t feasible do you layer in other measures like engineering controls, administrative controls, or PPE, each providing protection in a different way. For example, replacing a toxic chemical with a non-toxic one or redesigning a process to avoid the hazard entirely achieves top-tier protection, whereas relying on protective gear or warnings would be secondary safeguards.