HEPA filter based media is the gold standard for combating PM2. 5 pollution particles. Made of synthetic fibers, these filters trap the smallest particles, including pollen, dust, dander, and particulate pollution like PM2.

Experiments identifying PM 2.5 filter efficiency found that these MERV-7 category filters only remove between 2% and 21% of particles, whereas higher category filters such as MERV-16 and HEPA can remove upwards of 96%-100% (Azimi et al., 2014; Zhao et al., 2015) .

The term PM 2.5 is well-known in the air pollution control world. PM stands for particulate matter and PM 2.5 refers to very fine dust particles in the air that are 2.5 microns or less in diameter and includes inhalable particles small enough to penetrate the thoracic region of the respiratory system.

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