How should FFU choose based on project requirements when using HEPA and ULPA?
Basic Differences between HEPA and ULPA
The filters used by FFU are mainly divided into two categories: HEPA and ULPA. HEPA filters are divided into efficiency levels such as H13 and H14 according to EN1822 standards, and have high filtration efficiency for 0.3 micron particles. ULPA filters are divided into U15, U16, U17, etc., which have higher filtration efficiency for smaller particles.
Both are used for particle control in clean rooms, but have different efficiency levels and different applicable scenarios. Which filter to choose should be based on the project cleanliness level, process sensitivity and FFU complete machine matching.
Aili Industry has complete production capabilities in FFU complete machines and high-efficiency filters, and can provide HEPA and ULPA filter configuration solutions. For the basic structure of the FFU machine, you can refer toAili Industrial FFU fan filter unit。
How does cleanliness level correspond to filter selection?
Different cleanliness levels have different requirements for filter efficiency. ISO Class 5 to Class 6 can typically use H13 or H14 HEPA filters. ISO Class 3 to Class 4 may require H14 or U15. ISO Class 1 to Class 2 generally require U15 or higher efficiency ULPA filters.
For the relationship between filter grade and cleanliness grade, please refer towhy FFU filtration grade cannot be directly equivalent to ISO cleanliness grade . Understand Filter efficiency is only one condition for cleanliness. Room airflow organization, sealing and dust generation also affect the final cleanliness.
How process sensitivity affects selection
Different processes have different sensitivities to particles. Semiconductor lithography, wafer manufacturing and other processes are sensitive to tiny particles and may require ULPA filters. In general electronic assembly, PCB production, food packaging and other scenarios, HEPA filters may meet the requirements.
Medical and biological clean areas also have requirements for microorganisms and particles, and filter selection needs to be combined with relevant specifications. If the project has special process requirements, it should be confirmed with the process party.
How resistance affects overall machine matching
ULPA filters are more efficient, but generally have higher resistance than HEPA filters. After the resistance increases, the working point of the FFU fan moves and the air volume may decrease. If the FFU fan static pressure margin is insufficient, the target air volume may not be maintained.
When selecting a ULPA filter, the static pressure capacity of the FFU at the target air volume should be rechecked. For details, please refer toWill the air volume be affected when the FFU filter level is increased? Understand the impact of resistance. If the resistance increases significantly, you may need to select an FFU with a larger fan capacity or adjust the control method.
How to cooperate with sealing methods
Both HEPA and ULPA filters require properly installed seals. Common sealing methods include gasket seals and liquid tank seals. Liquid tank seals are usually used in scenarios with high sealing requirements, such as semiconductor and pharmaceutical clean rooms.
When selecting a filter, make sure that the sealing interface of the FFU box matches the sealing method of the filter. For details, please refer toHow to choose FFU liquid tank seal and gasket seal and understand the sealing method.
How to check filter size and thickness
HEPA and ULPA filters can vary in size and thickness. When selecting, make sure that the installation dimensions of the filter and FFU box match, and that the thickness of the filter does not affect the pressing mechanism and maintenance space.
If the filter thickness changes, the FFU maintenance structure and fan operating points should be rechecked. For details, please refer toAfter the FFU filter thickness is changed, why should we recheck the fan and maintenance structure ?
Aili industrial filter accessories
Aili Industry has complete production capabilities in FFU complete machines and high-efficiency filters, and can provide filters and complete machine matching solutions with different efficiency levels from H13 to U17. The filter adopts a one-by-one scanning leak detection process, and the detection data is associated with the complete machine number.
If the project requires ULPA filter matching FFU, you can refer toFFU is equipped with ULPA ultra-high efficiency filter to understand the interface and configuration. If the project requires liquid tank sealing ULPA filter, you can refer toLiquid tank seal ULPA ultra high efficiency filter。
Issues that should be confirmed in advance during project communication
During the FFU filter selection stage, it is recommended to confirm the following with the FFU manufacturer and process party: target cleanliness level; process particle sensitivity; filter efficiency level; filter resistance and size; FFU fan static pressure margin; sealing method; maintenance space; detection and leak detection requirements.
If you are choosing a HEPA or ULPA filter for your FFU, you can visitAili Industrial FFU fan filter unit to learn about the complete machine configuration, you can also refer toLearn about HEPA and ULPA filters with different efficiency levels, or contact Aili Industrial for selection support.
in conclusion
Whether FFU uses HEPA or ULPA filters should be judged based on the target cleanliness level, process sensitivity and filter resistance. ULPA is more efficient, but the resistance may increase, and the fan operating point needs to be checked. The sealing method, size and maintenance space also need to be confirmed simultaneously.
Aili Industry has complete production capabilities in FFU complete machines and high-efficiency filters, and can provide HEPA and ULPA filter configuration solutions. If you need to know more about FFU filter selection, you can visitAili Industrial FFU fan filter unit , you are also welcome to contact Aili Industrial for project support.
