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  • Writer's pictureCleanroomsUSA

Cleanroom Air Filters

The cornerstone of a cleanroom's functionality lies in its filtration system, tasked with maintaining its pristine environment. Cleanrooms, classified according to ISO standards, utilize single or multiple filters, typically positioned within the ceiling. Air circulates from ceiling to floor, exiting through floor ducts.

High Efficiency Particulate Air (HEPA) filters, capable of trapping 99.97% of 0.3 μ-sized particles, are standard, with diverse designs catering to different cleanroom specifications. Constructed from intricately woven fibers, smaller than 1μ in diameter and spaced less than 0.5 µ apart, HEPA filters boast a randomized configuration to thwart pattern formation.

Despite their efficacy, the complexity of HEPA filters induces pressure drops in airflow, necessitating fan systems to maintain consistent flow. This upkeep can incur substantial power costs as pressure drop escalates with filter clogging.

Pre-filters act as a frontline defense, capturing larger particles before air reaches HEPA or Ultra-Low Particulate Air (ULPA) filters, thus prolonging their lifespan. However, frequent monitoring is imperative as pre-filters saturate swiftly.

ULPA filters, akin to HEPA filters but more efficient, eliminate 99.95% of 0.12 µm contaminants, albeit at a higher cost. Available in various sizes, ULPA filters optimize efficiency while minimizing pressure drop.

HEPA filters, renowned for their effectiveness in removing 99.99% of 0.3 µm particles, stand as the preferred choice for many cleanroom applications. With minimal pressure drop and maximal airflow, HEPA filters can endure for years, contingent upon particulate levels. Notably, their random fiber arrangement enables effective capture of erratically moving microscopic particles through Brownian motion.

In unidirectional systems, HEPA or ULPA filters are strategically positioned to facilitate optimal airflow and particle capture. An aluminum-framed HEPA filter, tailored for industrial use, exemplifies this advanced filtration technology.

Contact us today and one of our cleanroom experts will discuss the best path forwards for your project.


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