what types of specs should I look for when purchasing an infrared camera to detect water leaks and fire damage?

The type of camera you are looking for may not be a traditional one for taking pictures. All you need is the IR sensor and an LCD to view the image. The concept is simple. Water logged materials would be "colder" than normal while fire damaged (if very recent) should be "hot" hence they will appear different in the LCD compared to normal surfaces. I really have no idea how these cameras look like (maybe a drop-in instrument or even pistol-like) or where to find them (probably scientific instruments or home improvement depots) but I'm pretty sure they exist.

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http://www.flir.com/thermography/americas/us/view/...