Fine dust is a very small material that is invisible to the naked eye. It is a particulate material with a diameter of 10μm or less that floats or floats in the air for a long time. When fossil fuels such as coal and petroleum are burned, it comes out.
The World Health Organization (WHO) has designated BC (black carbon) as a first-level carcinogen in diesel particulates. When exposed to fine dust for a long time, the immunity is rapidly lowered, and it can be exposed to various diseases such as cardiovascular diseases, skin diseases, eye diseases, as well as respiratory diseases such as colds, asthma and bronchitis. Ultra-fine dusts with a diameter of less than 2.5μm are particularly susceptible to penetration into the bronchi and deep into the lungs of the human body.