Negative pressure weighing booth is a kind of partial purification equipment specially used for pharmaceutical,microbiological research and scientific experiments area.It provides a vertical unidirectional airflow,part of the clean  air circulates in the work area,and part is discharged to the nearby area,so    that the work area can generate negative pressure,prevent cross-contamina    -tion,and ensure a high cleanliness environment in the work area.
Making the weighing and packaging of dust and reagents in the equipment can control the overflow and rise of dust and reagents,prevent the inhalation hazards of dust and reagents to the human body,and also avoid cross-contamination of dust and reagents,and protect the safety of the external environment and indoor personnel.

1.The casing is made of high-quality SUS 304 stainless steel,which is simple and beautiful.
2.The return air plate at the windward terminal of the primary and medium efficiency adopts a quick-install structure, which is more convenient for the maintenance of the primary and medium-efficiency filters.
3.Configuration of high precision wind speed sensor and PLC automatic control system can accurately and stably adjust to preset wind speed.
4.The PLC automatic control system can automatically monitor the filter conditions at all levels,and automatically remind the user to replace the filter when the preset final resistance is reached.
5.The PLC automatic control system can automatically capture the fault signal,and can automatically alarm and automati- cally shutdown when the fault occurs,thus effectively protecting the users and production materials.                                
6.The modular design is convenient for handling and on-site assembly.

Structure  diagram:
1.Air outlet
2.PAO inspection hole
3.PAO Sampling outlet
4.HEPA differential pressure gauge    
5.Control panel and operation button
6.Waterproof socket
7.Air return hole
8.Air duct
9.Fan
10..Bag type medium efficiency filter  
11.Primary efficiency filter
12.Gel Seal HEPA
13.Lamp and UV sterilization lamp    
14.Air flow equalizing mesh
15.Negative pressure working area

After the weighing room is powered on, the air in the clean room passes through the primary filter and the medium filter, and is pressed into the static pressure box by the centrifugal fan. After passing through the high-efficiency filter, it is blown out from the outlet surface of the uniform flow membrane. The clean air flows through the working area at a uniform cross-sectional wind speed, thus forming a highly clean working environment. The air flow blows into the return air port from top to bottom. The return air port is equipped with a filter to filter the polluted air in the weighing room and send it back to the static pressure box of the weighing room for repeated purification. In order to maintain the negative pressure state of the weighing room operation area, the weighing room will exhaust 10% of the circulating air to keep the weighing room in a state of slight negative pressure.