What is a consequence of compression on the thermal barrier material?

Compression on thermal barrier materials leads to the expulsion of air from within the material's air pockets. This is an important mechanism because the trapped air contributes to the insulation properties of the material. By forcing out this air, the thermal barrier may become less effective, as the insulation relies on the presence of air pockets to reduce thermal conductivity. As air is a poor conductor of heat, its removal can compromise the material's ability to resist heat transfer, which is critical in maintaining appropriate body temperatures in high heat environments. Understanding this principle helps in assessing the durability and effectiveness of protective gear used in firefighting and other hazardous conditions.