What is the best way of limiting exposure to toxic substances?

• A. By shortening the shift length
• B. By promoting self-monitoring only
• C. By using non-toxic substances
• D. By increasing PPE usage only

Answer: (C)

Replacing hazardous materials with non-toxic or less toxic ones is the most effective way to limit exposure because it removes or reduces the hazard at its source. This approach aligns with the top of the hierarchy of controls, where eliminating or substituting the hazard has the biggest impact on risk and reduces the need for other controls downstream.

Shortening shift length lowers the time a worker is exposed, which helps but doesn’t remove the hazard itself. Self-monitoring focuses on detecting exposure after it occurs, not preventing it. Relying on PPE alone shifts the burden to the worker and depends on proper use and equipment integrity. Substitution—or using non-toxic substances—directly reduces the potential dose and exposure risk, making it the best choice.