Abstract: A device for detecting the heat of an area, such as a door within a burning structure, can be attached to garments worn by a firefighter or rescue personnel. The device includes a temperature probe through which light emitted by the target area enters, striking a temperature sensor which is in electronic communication with a microprocessor, an alarm circuit, and a visual display. If the detected temperature exceeds a specified threshold, the alarm goes off, warning the user of a potentially dangerous situation. By wearing a device either attached to a helmet, sleeve of a jacket, or boot, the user can readily detect the temperature, without adversely affecting their ability to carry equipment necessary to deal with an emergency situation.