All kinds of harmful gas in the air and material such as smoke, dust, exhaust, odor and chemical substances such as formaldehyde, benzene, ammonia, and everyday life TV, PC, mobile phones and other electronic products and electrical equipment of electromagnetic wave to form positive ions in general. Once ingested, it weakens cell activity, reduces the ability of cells to absorb nutrients, excretes waste, and harms people's health. The negative ions can neutralize the positive ions and restore the active oxygen (oxygen free radicals) produced from the atmosphere, such as pollutants, nitrogen oxides, formaldehyde, and cigarettes. To bring the positive electric air to dust without charge; Reduce the radiation hazard of electromagnetic wave, so that the environment can be purified. In addition, negative ions are identified as an effective means of killing germs and purifying the air. The mechanism is mainly the combination of negative ions and bacteria, causing the bacteria to produce structural changes or energy transfer, resulting in bacterial death.