What is a HEPA filter? Where are HEPA filters used in cleanroom? These are top 5 questions people frequently ask about High-Efficiency Particulate Air (HEPA) filters. Let's find out!

1. What is the actual size and nominal size of the HEPA filter with or without clapboard?

Whether there is a partition or not, the actual size and nominal size of the HEPA filter are divided. This is because the nominal size is the filter including the outer frame and the filter material, and the actual size generally excludes the outer frame, and only the width of the filter material is calculated.

2. What are the similarities and differences between HEPA filters with and without partitions?

HEPA filters can be divided into high-efficiency filters with partitions and high-efficiency filters without partitions.

The partitioned HEPA filter is made of ultra-fine glass fiber as the filter material, rubber paper, aluminum platinum as the partition board, and the wooden frame or aluminum alloy frame. It has high filtration efficiency, low resistance, and large air volume. The outstanding advantage of partitioned HEPA filters is the filters are widely used in various local purification equipment and clean rooms.

The partitionless HEPA filter uses ultra-fine glass fiber as the filter material and hot melt adhesive as the separator. It is assembled with various outer frames. Compared with the partitioned HEPA filter, it has the same air volume. It has the advantages of small size, lightweight, compact structure, and reliable performance.

3. What are the standard folding numbers, folding heights, and formula conversions of HEPA filter media with and without partitions?

The folding height of the filter paper with partitions is generally about 30mm~34mm shorter than the height of the nominal size.

The folding number is mainly determined by the tightness of the partition paper and the assembly of the filter paper and the partition paper.

The curvature of the partition paper is in accordance with the standard. The number of folds of filter paper without partitions is mainly determined by the folding height of the filter paper and the tightness of the filter paper.

4. What are the similarities and differences between "PP HEPA" and glass fiber HEPA filter?

Features PP HEPA filter Glass fiber HEPA filter Skin irritation No Yes Fiber shedding No Harmful to human body Filter effect Good Good Wind resistance Small Equal to PP HEPA filter

5. What is HEPA filter material?

The outer frame is aluminum alloy frame, multi-layer frame, aluminum frame, galvanized steel frame

HEPA filter material: glass fiber is mostly used, and chemical fiber is gradually being used. Currently, some foreign manufacturers use electrostatically charged polytetrafluoroethylene fiber (electret) to manufacture HEPA filters, commonly known as PTFE.


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