What is the difference between source control and personal protective equipment (PPE) in exposure management?

• A. PPE is the primary method to reduce emissions at the source.
• B. Source control reduces contaminants at the source; PPE protects the worker after exposure occurs.
• C. Both are equally effective at reducing exposure.
• D. Source control and PPE do not affect exposure.

Answer: (B)

The key idea is how exposure is controlled along the chain from release to the worker. Source control targets the hazard at its origin, using engineering measures to remove or greatly reduce contaminants before anyone can be exposed—think enclosing processes, local ventilation, or process changes. PPE, in contrast, is a protective layer used when some exposure could still occur; it shields the worker by acting as a barrier after release or when engineering controls can’t eliminate the hazard entirely.

That’s why the option stating that source control reduces contaminants at the source and PPE protects the worker after exposure is the best fit. It reflects the hierarchy of controls: prioritize reducing or eliminating the hazard at the source, and use PPE as a secondary safeguard. The other statements mischaracterize the relationship: PPE does not reduce emissions at the source, and declaring both controls equally effective or that they don’t affect exposure ignores how engineering controls reduce overall risk and how PPE depends on proper use and may not fully prevent exposure.