Skin burn injuries and heat stress/fatalities
Firefighters are exposed to a significant amount of thermal energy in a fire hazard, which may transfer through firefighters’ clothing toward their bodies. This thermal energy transfer depends upon fabric properties and clothing structure. The thermal energy transmitted may cause burns on human (in this case, firefighters’) skin. Scientifically, human skin is broadly divided into two layers: epidermis and dermis (Fig. 3.1) [115-117]. The epidermis is the outermost layer of skin, and its thickness is ^0.4-0.6 mm; below the epidermis, a thick layer of ~1-4 mm exists, which is called the dermis. A thick layer of ~ 1.5-2 cm hypodermis/subcutaneous tissue exists below both layers of skin. Nerves, sweat glands, sebaceous glands, blood vessels, touch receptors, and hair follicles are present within two of these layers—dermis and hypodermis/subcutaneous. During exposure to thermal energy, heat transfer occurs throughout the human body, and causes burn injuries on the skin layers; in addition to burns, heat stress may occur due to heat transfer from the skin to the core [118-121].
Fig. 3.1 Diagram of human skin.