Which of the following layers is not a component of a protective bunker coat?

A protective bunker coat, designed for firefighter safety, consists of several essential components that serve specific purposes during operations. The outer shell serves as the first line of defense against external threats, such as water, chemicals, and physical abrasions. The moisture barrier plays a vital role in preventing moisture from penetrating the coat while still allowing sweat to escape, thereby keeping the firefighter dry and comfortable. The thermal barrier is critical for providing insulation against heat, which is crucial during firefighting scenarios to protect against thermal injury.

In contrast, a breathable lining is not a standard component of a bunker coat. While comfort and moisture management are important, and some bunker gear may incorporate materials that offer enhanced breathability, the fundamental layers that are defined in firefighting protective gear focus on the outer shell, moisture barrier, and thermal barrier. Breathable linings may exist as part of advanced designs, but they are not universally recognized as core components of a protective bunker coat.