1, the principle of slow movement:

In order to avoid affecting the normal state of the wind path, the cabinet should be operated when the hand should try to move as slowly as possible. 

2, items placed parallel to the principle:

In order to avoid cross-pollution phenomenon between the items the items, the items placed in the cabinet should be placed as far as possible in a horizontal word, to avoid cross-pollution caused by the process of wind back. At the same time to avoid blocking the back of the return air grille affecting the normal wind path.

3, avoid vibration principle:

Cabinet try to avoid vibration instrument (such as centrifuges, vortex oscillators, etc.) the use of vibration will make the accumulation of particulate matter on the filter membrane shaking off, resulting in a reduction in the cleanliness of the operating room inside, if the balance of the front operating surface failure will also cause the safety cabinet on the operator's contamination. 

4, the principle of moving different samples within the cabinet:

Cabinet of two more items need to move, must follow the low contamination items to high contamination items to move the principle of avoiding high contamination items in the process of moving to produce a large area of pollution inside the cabinet.

5, the use of open flame principle:

Cabinet try to use open flame. Because the use of open flame in the process of fine particles of impurities will be brought into the filter membrane area, these high-temperature impurities will damage the filter membrane. Can be avoided must need to use, it is appropriate to use a low flame Bunsen burner.