The advised numbers of lower limit air speed of one-way current of clean room:
The smallest air speed to ensure that the clean room can control the following four kinds of pollution:
A. When the pollution air current multi-directionally spread, the air-supply current should be effectively control the range of the pollution;
B. When the pollution air current and air-supply air current are the same direction, the air-supply air current should be effectively control the spread range of the pollution air current reaches the lower place;
C. When the pollution air current and air-supply air current are not the same direction, the air-supply air current can control the pollution air current in the essential range;
D. Under the condition that the whole clean room is polluted, it will have enough time to clean the indoor room by itself at a suitable period.