Because of the thin limestone layers above (10-30m) the temperature of the cave is quite high (15-17oC)
Temperature is stable even in the winter because the airing of the cave is less than the proper
In May humidity is high (95-105%) and it's quite stable all year long
The average quantity or carbon dioxite is 600PPM(0.06%). According to a study of the atmospheric conditions of the cave all chambers are sufficiently air-filled. The temperature inside the cave is stable all year long for the formation of a cubic centimeter of a stalactite it will take at least 100 years.
According to Dr.Seeman, the Austrian official researcher of the cave, the last time a rock fell was 700.000 years ago.