Lt. D. Rehbeck of the Newark Fire Department during a recent house fire. The gray background around his hand and the camera is heavy smoke as the camera is pointed at the living room window. The light glow area of the photo is the "hot" area, showing firefighters where there is most likely fire above the ceiling and in the walls. The dark areas are "cooler" areas that have not absorb so much heat (but you still would not want to touch the items with your hand).
The dark black area is actually the hose stream being shot onto the ceiling from the firefighters standing at the front door, thus the water is cooler from the 15 degree temperature during the early morning fire. This has become a great tool not for just finding the seat and hot spots of a fire, but also locating any victims to rescue who could not get out of the fire building.
A thermal imaging camera can be purchased for around $10,000.
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