Virtually all particles in the air have a positive charge, while negative ions have a negative charge. In which case, negative ions and particles magnetically attract to one another. When there is a high enough concentration of negative ions in the air, they will attract to floating particles in large numbers. This causes the particle to become too heavy to remain airborne. As a result, the particle will fall out of the air, preventing it from being inhaled into the respiratory tract where it can trigger breathing and health problems.
The ionized particle will then be collected by normal cleaning activities, such as vacuuming or dusting. If the particle happens to be kicked back up into the air again, it will be ionized, and quickly settled out of the air once again.
In nature, negative ions are generated by processes such as sunlight, lightning, waves from the ocean, and from waterfalls. "Concrete Jungles" minimize the natural production of negative ions by disrupting the delicate electrical balance between the atmosphere and the earth. Aqua Sun Ozone International recreates them with electrode pins ("needlepoints") to electrically produce negative ions. This method produces a density that is many times higher than the negative ion level found at Niagara Falls, the highest natural producer of negative ions and one of the healthiest environments in the world.
What does Ozone do?
Corona Discharge vs. UV Ozone Generation