Which material is commonly used for insulation in firefighting gear?

The common use of Kevlar in firefighting gear is primarily due to its excellent strength-to-weight ratio and heat resistance. Kevlar is a synthetic fiber that is known for its ability to withstand extreme temperatures and is highly durable, which is essential for protection against the intense heat and flames firefighters encounter. In addition to its thermal insulation properties, Kevlar is also lightweight, allowing for enhanced mobility and comfort for firefighters while performing their duties.

Other materials listed like wool, fiberglass, and mylar have their applications but do not provide the same level of heat resistance and protective qualities that Kevlar does. Wool, for example, can offer some level of insulation but is not as effective in high-heat situations. Fiberglass is used in some applications for its thermal resistance but isn't as commonly used in personal protective equipment for direct contact. Mylar is more associated with reflective properties and insulation in a different context, rather than direct use in firefighting gear. Thus, Kevlar's specific attributes make it the optimal choice for insulation in firefighting gear.