Our screens are not used the same way as conventional filters, although it can be considered a filter.
Conventional filters are build differently and have many layers to prevent particles to pass through, these can reach efficiencies of almost 100%.A particle can have many different shapes. For example a hair has a diameter Ø 0,1mm but the length can be centimeters long. If the hair arrives perpendicular to the screen it might pass a 100 mesh screen. With a conventional filter the second or third layer will prevent the hair to pass.
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