What are the grades of G, F, H, and U for air filters?

G, F, H, and U in the specifications of air filters are the classification of grades, specifically based on the European standards. European standards are divided into four levels: G, F, H, and U. U refers to ultra-high efficiency; H is ordinary and efficient; F is medium efficiency; G means initial effect; For example, G4 is a European standard primary air filter with a filtration efficiency of around 40%. Air filters have different standards in different countries. China's national standards are divided into three levels: primary filters, medium filters, and high-efficiency filters. 

1. Primary air filters are suitable for primary filtration in air conditioning systems, mainly used to filter dust particles larger than 5 μ There are three styles of primary filters: plate type, folding type, and bag type. The outer frame materials include paper frame, aluminum frame, and galvanized iron frame. The filter materials include non-woven fabric, nylon mesh, activated carbon filter material, metal mesh, etc. The protective mesh includes double-sided spray coated wire mesh and double-sided galvanized wire mesh. The characteristics of primary filters are: low cost, light weight, good universality, and compact structure. Mainly used for: a. pre filtration of central air conditioning and centralized ventilation systems; b. Pre filtration of large air compressors; c. Clean return air system; d. Pre filtration of local high-efficiency filtration device; e. High temperature resistant air filter, with a stainless steel frame and a filtration efficiency of 250-300 ℃. The G series primary air filter has low resistance; High air volume; Long lifespan when used. This type of efficient filter is commonly used for primary filtration in air conditioning and ventilation systems, and is also suitable for simple air conditioning and ventilation systems that only require primary filtration.

2. Folding medium efficiency air filter is used for filtering ventilation systems. General air purification in fields such as electronics, pharmaceuticals, mechanical instruments, metallurgy, petroleum, chemical, light industry, and food. Features: High efficiency, large dust holding capacity, and small space occupation.

3. Bag type medium efficiency air filter is used for central air conditioning centralized ventilation systems or as a pre filter for high-efficiency filters. It can reduce the burden of high-efficiency filters, extend their service life, and can also be used for general air purification in industrial fields. Features: Low resistance, large dust holding capacity.

Medium efficiency filters are mainly used in central air conditioning and centralized air supply systems. It can be used for primary filtration in air conditioning systems to protect the lower level filters and the system itself. In places where air purification cleanliness requirements are not strict, the air treated by the medium efficiency filter can be directly sent to the user. The frame of the medium efficiency bag filter is in the form of cold plate spray coating, zinc plated plate, etc. The filter material includes non-woven fabric, glass fiber, etc. The filter particle size is 1-5um, and the filtration efficiency is 60-95% (colorimetric method). Medium efficiency air filters are mainly used to capture particles of 1-5 μ m dust and various suspended solids. They are widely used in various air conditioning equipment and systems, as well as for intermediate protection in multi-stage filtration systems. This series of products mainly have a bag structure, and the outer frame materials include aluminum alloy, galvanized steel plate, and can also be made frameless. The filter material is mainly non-woven fabric. 1) Function: Capture 1-5um dust particles 2) Type: frameless and framed bag 3) Filter material: special non-woven fabric or glass fiber 4) Efficiency: 60% to 95% @ 1-5um (colorimetric method) F series medium efficiency air filters are divided into bag and non bag types, with bag type including F5, F6，F7，F8，F9， Non bag filters include FB (plate type medium efficiency filter), FS (partition type medium efficiency filter), and FV (combination type medium efficiency filter).

Suzhou Pharma Machinery Co.,Ltd.

2025/02/28

Gino