What high-efficiency filter does the vertical flow table use?

Vertical flow workstations typically use high-efficiency air filters (HEPA) and ultra-high-efficiency air filters (ULPA) to ensure air cleanliness in the work area.
High-Efficiency Air Filter (HEPA)
Filter principle:
HEPA filters filter particles in the air mainly through a variety of mechanisms such as screening effect, inertial collision, interception, and diffusion. Among them, the screening effect is the key, the tiny airway formed between the filter paper fibers precisely sets the "entry threshold", only those air molecules with a diameter smaller than the airway can pass smoothly, and the slightly larger dust, microorganisms and other particles are blocked on the filter paper surface.
When the air flows through the HEPA filter, the larger particles are caught because of inertia. When the air flows through the zigzag channel of the filter screen, they have no time to change their direction and hit the fiber surface directly. Some smaller particles try to "sneak through" under the airflow but are blocked by the tight arrangement between the filter fibers. There are also some very small particles that continue to do irregular diffusion due to Brownian motion, increasing the probability of contact with the fiber, and eventually being adsorbed and retained.
Filtration efficiency and accuracy:
Generally, for particles with a particle size of 0.3 microns, the filtration efficiency is as high as 99.97% and above. This means that it can effectively filter out bacteria (bacteria size is generally 0.5-5 microns), fungal spores (size is about 1-100 microns), some viruses (virus size range from 0.02 to 0.3 microns), and fine dust.
Application scenario:
In the medical field, such as hospital sterile operating rooms, drug dispensing rooms, etc., HEPA filters can filter out bacteria and viruses in the air, providing a sterile environment for medical operations, and reducing the risk of surgical infection and the possibility of drug contamination.
In the biological laboratory, for cell culture, microbial detection, and other experiments, it can prevent outside microorganisms from entering the work area to ensure the accuracy of the experimental results.
In some production links in the electronics industry where the cleanliness requirement is relatively not the highest, such as the assembly workshop of electronic components, HEPA filters can reduce the pollution of dust on electronic components and reduce the incidence of failures such as short circuits of components.
Ultra-high Efficiency Air Filter (ULPA)
Filter principle:
ULPA filters work similarly to HEPA filters and are also based on a variety of physical mechanisms. But its filter paper material is finer, the fiber is finer, and the formation of a narrower airway. This structure allows it to filter even smaller particles efficiently.
Filtration efficiency and accuracy:
The filtration accuracy of the ULPA filter can reach 0.1-0.2 microns, which can capture extremely small particles missed by the HEPA filter. Its filtration efficiency for 0.12-micron particles can be as high as 99.999% or more, and almost all small impurities in the air can be intercepted.
Application scenario:
In scenarios where cleanliness is almost critical, such as chip manufacturing lithography workshops, ultra-clean laboratories, etc., ULPA filters can provide clean air at the "cleanliness freak" level. In the chip manufacturing process, lithography is an extremely precise link, any small dust particles may cause defects in the chip circuit, ULPA filters can ensure that each chip circuit is etched without dust interference, thus guaranteeing the quality and performance of the chip.