1 High speed straight blowing human body, bring many health problems;
2 It is easy to absorb the dust in the air under the operation of high speed, it is not easy to clean, and seriously affect the service life;
3) The coverage is very small, the energy consumption is high;
4 industrial plants and large venues to use, affecting the beauty of the workshop and venues.
5 The use of extremely inconvenient, and easy to bring security problems.