I know of 3 main uses of Thermal imaging: -
1) To ensure compliane with the rules regarding maximum permitted surface temperatures on machinery. Taking Thermal Images of the exaust manifolds and pipework of diesel Engines, steam pipework, steam engines, HFO pipework etc can reveal where the insulation is substandard and has ti be improved, or, if you are lucky, that everything on your ship is compliant.
2)It is often used as part of the survey of Electrical Installations. If there is a high electrical resistance in an electrical connection, it will generate heat. (Heat radiated = Current squared x resistance). Usually this is due to a loose connection and or corrosion on the contact faces.
The difficulties with this is that you have to open the doors on your live switchboards, and preferably power up everything running on the switchboard to full load, then take your pictures. Often a difficulty that you can not stand far enough back from the switchboard to photograph more than a very small area at a time. Also if some shore contractor comes onboard to take the pictures while you are in Port it is difficult to run all the main propulsion Motors, Thrusters, cargo pumps etc at full load while you are alongside.
I think it is usually best if an expert Thermal Imaging photographer sails with the ship, and then when you are at Sea you can load up each section of the switchboard in turn so that they can be photographed. It is a complete waste of time taking pictures of a "Dead" switchboard.
3) It can be used, from inside refrigerated containers or cargo holds, or even refrigerated store rooms onboard, to detect "Hot Spots" where heat is leaking in through poor insulation.
Hope this helps.
It is always better to ask a stupid question than to do a stupid thing.