The book discusses an exceptional use of an extraordinary material in a new field. While the era of nano technology is knocking our door, novel materials like aerogel are emerging. Aerogel is called as space age material. The book shows the use of aerogel nano particles in firefighter's protective clothing. Aerogel is a flame proof, extremely light weighted and lowest density solid on earth that can provide impressive thermal insulation. NASA uses aerogel to develop equipment and space suit which requires protection against extreme cold. Aerogel research has been carried out for insulation against cold in space, architecture and apparel. However the book has revealed the use of super insulation property of aerogel against heat in firefighter's protective clothing. Thermal-physical comfort of a firefighter seriously hampers due to internal heat which develops from their bodies as a result of movement with loads of equipment, if their protective clothing does not allow the release of body temperature and sweat. The book investigates the thermophysiological comfort of aerogel coated turnout gear fabric by analyzing air, heat flux and moisture transportation properties.