When it comes to air filtration, there are two main types of filters: HEPA and ULPA. HEPA filters are extremely efficient and effective, trapping 99.7% of air pollutants as small as 0.3 microns. ULPA filters, on the other hand, are even more effective, trapping 99.999% of particles 0.12 microns in diameter or larger. The MERV Ratings Chart and Filter Type and Particulate Removed can help you decide which filter is best for your needs.
HEPA filters are at the highest MERV level and work best with protection against air pollutants. However, if you're looking for a filter that can capture tiny particles, an ULPA filter may be the better option. When it comes to air purifiers, the Molekule Air is a popular choice. In Auto mode, the air performed worse than expected, reducing particles from 0.3 microns in only 18.0% (ambient) and 26.4% (clean).
In Silent mode, it performed even worse, reducing 0.3 micron particles by 6.5% (ambient) and 7.2% (clean). And in Dark plus Auto mode, with its primary PECO purification system turned off and its fan at the equivalent of a medium setting, it reduced them by 21.3% (ambient) and 18.0% (clean). These results suggest that the Molekule Air relies primarily on its physical prefilter, not its patented PECO mechanism, to remove particles. This means that if you're looking for a filter that can remove particles such as pet dander, dust, pollen, and mold spores, a HEPA filter is your best bet. However, if you're looking for a filter that can reduce particles of smaller sizes and larger particles, an ULPA air filter may be the better option.
Considering the threat posed by the spread of COVID-19 and other germs, upgrading a building's air filter to an ULPA is a much more effective step than just a MERV 13. When shopping for an air filter or purifier, make sure to look for one that includes a pre-filter, HEPA filter and carbon filter in the same medium. This will ensure complete odor and VOC filtration without sacrificing airflow or causing more harm than good.