Which example represents an engineering control in the hierarchy of controls?

Which example represents an engineering control in the hierarchy of controls?

• A. Substituting a toxic solvent with a less hazardous one.
• B. Installing local exhaust ventilation.
• C. Rotating workers between tasks.
• D. Wearing respirators.

Answer: (B)

Engineering controls reduce exposure at the source by changing the equipment or process so the hazard is removed or greatly diminished without relying on what workers do. Local exhaust ventilation is a classic engineering control because it captures contaminants right where they’re generated—at the source—using hoods, ducts, and fans to pull vapors away before they disperse in the room. This directly lowers the concentration workers are exposed to, independent of their actions. Substituting a toxic solvent with a less hazardous one is a substitution or hazard elimination step, also highly effective but not an engineering control per se. Rotating workers between tasks is an administrative control that changes how work is organized to reduce exposure but doesn’t remove the hazard itself. Wearing respirators is PPE, the last line of defense that relies on proper use and protection if other controls aren’t sufficient.

Engineering controls reduce exposure at the source by changing the equipment or process so the hazard is removed or greatly diminished without relying on what workers do. Local exhaust ventilation is a classic engineering control because it captures contaminants right where they’re generated—at the source—using hoods, ducts, and fans to pull vapors away before they disperse in the room. This directly lowers the concentration workers are exposed to, independent of their actions.

Substituting a toxic solvent with a less hazardous one is a substitution or hazard elimination step, also highly effective but not an engineering control per se. Rotating workers between tasks is an administrative control that changes how work is organized to reduce exposure but doesn’t remove the hazard itself. Wearing respirators is PPE, the last line of defense that relies on proper use and protection if other controls aren’t sufficient.