Which PPE component limits evaporation of sweat?

Which PPE component limits evaporation of sweat?

• A. The liner reflects evaporative heat
• B. Perspiration is absorbed in the layers
• C. The thermal barrier prevents heat transfer
• D. The vapor barrier limits evaporation of sweat

Answer: (D)

Sweat cooling mainly comes from evaporation. A vapor barrier is the layer designed to stop water vapor moving through the suit. By blocking that movement, it traps perspiration inside and prevents it from evaporating at the outer surface, which reduces evaporative cooling. That’s why this barrier limits sweat evaporation. The other layers have different roles—some insulate to slow heat transfer, others manage moisture for comfort—without specifically blocking sweat evaporation throughout the suit.

Sweat cooling mainly comes from evaporation. A vapor barrier is the layer designed to stop water vapor moving through the suit. By blocking that movement, it traps perspiration inside and prevents it from evaporating at the outer surface, which reduces evaporative cooling. That’s why this barrier limits sweat evaporation. The other layers have different roles—some insulate to slow heat transfer, others manage moisture for comfort—without specifically blocking sweat evaporation throughout the suit.