The Thermal Survival Helmet links with the Thermal Survival Suit to provide complete body protection for the wearer from excessively high temperatures. Typically, the helmet features a multi-layer construction with an outer shell of heat reflective material and an inner layer of hollow coils through which liquid or gel coolant is circulated. Both coolant and power to circulate it are normally supplied via a series of links and jacks connecting the helmet to the Thermal Survival Suit.
A helmet of this type will also be equipped with external microphones to pick up sound as well as a respirator that either attaches to a closed-circuit air supply or has heat dissipating functions to cool atmospheric gasses breathed in by the wearer in order to prevent burn damage to the respiratory system. Optical systems vary with the cost of the equipment, from a simple transparent faceplate to sophisticated ultrasonic radar that projects an image of the surroundings based on reflected soundwaves onto the internal heads-up display.