Some industrial facilities require thermogaphy inspection on set intervals. These test's are very good at identifying potential problems and allow you to act before the problem becomes a unexpected shut down or catastrophic failure of the equipment.
It is pretty expensive. But worth every dime if you are counting on the equipment not to fail as I mentioned above.
A good test will result in a picture, location, temp, and severity of the identified "hot spots".
It can also be a good tool on moving equipment like conveyors and motors. I had tech tell me which belt would fail first on a six belt pulley. I maked the belt and sure enough it did fail first. It's good for bearings too.
Overhead bus is another great example. No ladder, no opening of covers. Pic's performed from the floor. I am not sure how reliable this is though.
It's a great maintenance tool. We finally bought one for our company and sent one of our guys to school to learn how to operate it correctly.
