How does wearing PPE affect the body's ability to regulate temperature?

How does wearing PPE affect the body's ability to regulate temperature?

• A. Heat is efficiently conducted from the skin to the shell
• B. The perspiration-soaked inner liner enhances cooling by convection
• C. Cool SCBA cylinder air improves respiratory cooling
• D. PPE prevents evaporative cooling

Answer: (D)

Sweating is the body’s main way to dissipate heat during exertion. When full PPE is worn, the layering and sealed design trap heat and moisture and limit airflow around the skin. This prevents sweat from evaporating efficiently, so the body loses much less heat through evaporation and heat builds up. In other words, the protective gear acts as a barrier to evaporative cooling, making it harder for the body to regulate temperature. The other ideas describe cooling mechanisms that PPE does not enable—conducting heat into the suit adds heat, a sweat-soaked liner still can't evaporate effectively through the layers, and respirator air temperature isn’t a primary factor in cooling the body under PPE.

Sweating is the body’s main way to dissipate heat during exertion. When full PPE is worn, the layering and sealed design trap heat and moisture and limit airflow around the skin. This prevents sweat from evaporating efficiently, so the body loses much less heat through evaporation and heat builds up. In other words, the protective gear acts as a barrier to evaporative cooling, making it harder for the body to regulate temperature. The other ideas describe cooling mechanisms that PPE does not enable—conducting heat into the suit adds heat, a sweat-soaked liner still can't evaporate effectively through the layers, and respirator air temperature isn’t a primary factor in cooling the body under PPE.