The damp location is like a mushroom barn or even a regular barn. Subject to condensation.
It is a common misconception to think of a glued PVC pipe underground as Dry. The ground is cold and if the air is humid the water in the air can condense in the U/G pipe. Lots of dry pipes are wet pipes after a few years of collecting water from the air. Some ground slab pipes do stay dry but both ends are usually in the same building and the ground is at least partly heated by the building so the pipe stays above the dew point and the water stays in vapour. I have seen a few data runs where the wire was for a dry location and the cable in an underground location gets wet causing data troubles. Hard to gat a customer to install gel filled U/G cable at 10-20 times the cost of a regular cat5 cable or telco cable.
