THE THERMAL IMAGING CAMERA
The thermal imaging camera was developed in the 1980s by engineers from Great Britain. The system is based on a concept called the “pyroelectric effect.” In simpler terms, this means die camera can pick up minute variations in the electrical polarization of an object resulting from the difference in temperature between it and die objects around it. By differentiating objects by their thermal temperature, the camera is able to “see” through smoke and darkness. It enables its user to identify fire sources or the images of overcome victims much faster than conventional means can.
The camera is in a cylindrical container constructed of injectionmolded plastic, which provides protection against damage. The container is waterproof and sealed to conform with specifications for use in flammable atmospheres. The display is presented on a threeby five-inch cathode ray tube surrounded by a protective hood. It is a hand-held, battery-operated instrument weighing less than nine pounds. It lasts up to two hours on one set of batteries.
It is ideal for use in darkness; it can sense a living person from up to 2(X) feet away. However, it cannot “see” through objects. In heavy smoke or darkness, the camera will be able to distinguish objects by their thermal differences, but it will not “see” past obstructions such as concrete and masonry; even dry wall will block any readings.
As we operated in the bomb crater itself, the camera was an excellent tool for “panning” the entire surface for any exposed victims in a timely fashion. After this search was completed and the intensive search into the heavy debris of concrete slabs, destroyed cars, and other supplies and equipment was begun, the camera’s effectiveness was diminished due to the heavy mass of debris blocking any signs of trapped victims.
