Patent ID: 8896427

Claim:
A portable thermal image emergency exit marking device for use by firefighters and rescue personnel to mark an escape exit from a burning structure, comprising: a portable polygonal housing constructed of fireproof, heat and shock resistant material, having a top panel, a bottom panel, and side panels adapted to be placed in the burning structure; an electrical receptacle mounted on one of said panels for removably receiving a mating plug at the end of a waterproof insulated electrical cord connected to a remote electrical power source; electrical heating elements on said side panels connectable to said electrical power source, said heating elements formed of an electrical resistive metal material shaped to form heat generating words or symbols indicating an escape exit from the burning structure; and an adjustable electrical control switch mounted on said housing operatively connected between said electrical heating elements and said electrical power source to heat said electrical heating elements sufficient to emit thermal energy in the infrared wavelength band higher than the heat of the fire or environment of the burning structure in which said housing is placed so as to be clearly visible by a thermal imaging camera; such that said words or symbols formed by said heated electrical heating elements are discernable and clearly visible by the thermal imaging camera and are clearly distinguished from other hot spots, heat emitting objects, and burning objects in the environment of the burning structure to indicate the escape exit from the burning structure.