Many would miss this on a trivia quiz, but the skin is the human body's largest organ. And the importance for firefighters to protect their skin also goes largely unrecognized.
With a huge surface area and critical biological functions, the skin is key to providing a barrier to toxins and regulating temperature.
For the latter, the skin changes dramatically to provide thermoregulation and ensure proper cooling. It needs to function correctly for you to know when the heat is too much.