meaning of "damp" or "dampness"

Dear Ed,
Here in TCM, we use damp the same as dampness!
The poisonous gas is also mentioned in TCM, but not so often and so common. Sometimes in the tropic jungles, there could be such poisonous damp gas which could kill people.

But we don't really mean the poisonous gas in the coal mine, that's something else, not really regarded as something in concerns with medicine.

So, damp is the same as dampness in TCM, here in the texts of TCM.

Tutor