The concentration of dust particles in the atmosphere is an important factor affecting the cleanliness of clean rooms. If you want to effectively and adjustable control the cleanliness of the production and achieve the clean environment required for modern production, you must use filter paper filters and fiber layer filters, that is, air filters used in purification technology.

1. Classification of air filters:
According to the structure, there are:

• Plate filter

• Folder filter

• Bag filter

• Folding filter with partition

• Folding filter without partition

According to the filter efficiency, there are:

• Primary efficiency filter

• Medium efficiency filter

• Sub high efficiency air filter

• High efficiency filter

2. Selection and configuration of air filters

• For small purification equipment, such as clean workbench, air shower, laminar flow cover, etc., due to the small amount of air treated, the general fresh air inlet surface uses primary efficiency filter or medium efficiency filter; and the air supply end must use high efficiency filter ;

• For 1000-100,000 class clean room purification systems, the three-stage air filtration form is usually used, that is, the primary efficiency filter, medium efficiency filter and high efficiency filter. The primary efficiency filter and medium efficiency filter are generally placed in the air handling device, and the medium efficiency filter filter is placed in the positive pressure section. The high efficiency filter is generally located at the end of the purification air conditioning system;

• When the air handling volume of the entire purification system is known, the number of filters required can be determined according to the rated air volume of the selected filter.

3. Rate representation method of air filters

The primary efficiency filter is divided into four grades (G1~G4) :

• G1 for particle size ≥5.0μm, filtration efficiency E≥20% (US standard C1)

• G2 for particle size ≥5.0μm, filtration efficiency 50 > E≥20% (US standard C2~C4)

• G3 for particle size ≥5.0μm, filtration efficiency 70 > E≥50% (US standard L5)

• G4 particle size ≥5.0μm, filtration efficiency 90 > E≥70% (US standard L6)

The medium filter is divided into two grades (F5~F6) :

• F5 particle size ≥1.0μm, filtration efficiency 50 > E≥30% (US standard M9, M10 )

• F6 particle size ≥1.0μm, filtration efficiency 80 > E≥30% (US standard M11, M12 )

The sub high efficiency filter is divided into two grades (H10~H11) :

• H10 particle size ≥0.5μm, filtration efficiency 99 > E≥95% (US standard H15 )

• H11 particle size ≥0.5μm, filtration efficiency 99.9 > E≥99% (US standard H16 )

The high efficiency filter is divided into two grades (H12~H13) :

• H12 particle size ≥0.5μm, filtration efficiency E≥99.9% (US standard H16 )

• H13 particle size ≥0.5μm, filtration efficiency E≥99.9% (US standard H17 )

Suzhou Pharma Machinery Co.,Ltd.

2024/01/29

Tia