Question about wire inside of tubing

Question

I'm been looking for 45 minutes and everywhere I look there's answering going every which way but up, so I'm wondering if I want to run 12/2 wire above ground inside of conduit or pvc pipe, from the main breaker panel under the house to the small building, the building leaks in a few spots also once the conduit would stop from entering the 2nd small building ... I'm lost on which wire to choose to use in 1 in conduit, this would be 12/2 gauge wire, ? Nm-b, uf, uf-b, thhn, thwn... can someone shed some light on this subject for me please

Also if nm-b wire is used in pvc and it got wet somehow wouldn't the breaker trip or the gfci before any fire or spark

Answer 1

Underground conduit will fill with water. Fact of life. That's why you use wet rated wire in conduit.

You can direct bury cable or wire made for direct burial such as UF. It is made to be in contact with water.

If you use conduit you use wet rated wires like THWN. You can use wet-rated multiconductor cable if you really want to, but you will need bigger conduit and the pulls will be much harder.

Using NM outdoors is out of the question.