The crisp, refreshing air of the great outdoors (for example, in a forest) is clear and clean, and gives us an especially nice feeling. The reason for this is that there is a good balance of positive and negative ions in the air, that is, there are roughly the same number of each, and they are present in abundance. In the natural world, these positive and negative ions work to purify the air. But the quality of the air that most of us breathe is poor. It's often polluted and the number of ions it contains is low and the ratio of positive and negative ions is out of balance. To combat this problem, a new air cleaning technology, "Plasmacluster Ions," based on this natural air cleaning system is now available.