The main components of the volcanic gas are water vapor, carbon dioxide, and also sulfur dioxide (sulfurous acid gas). Usually small amounts of hydrogen gas, carbon monoxide, hydrogen sulfide, and hydrogen chloride are present. Some volcanoes may include hydrogen fluoride, silicon tetrafluoride, methane, ammonia, carbonyl sulfide, helium, radon, and mercury vapor, etc. These gases can cause great harm to animals and plants due to the toxic components and oxygen deficiency, and in many cases there is a large influence on the surrounding ecology due to the heat. At Hakone Ropeway, we constantly measure the gas concentration and operate in a way that ensures that our customers can enjoy the ropeway in safety.