Do HEPA (High-Efficiency Particulate Air) Filters Catch Viruses?

HEPA filter diagram

Yes, HEPA (High-Efficiency Particulate Air) filters are capable of capturing viruses, including some types of airborne viruses. HEPA filters are designed to capture particles as small as 0.3 microns with an efficiency of at least 99.97%. Many viruses, including common respiratory viruses, are larger than 0.3 microns, so a HEPA filter can effectively trap them and prevent them from circulating in the air.

It's important to note that while HEPA filters can capture viruses, they cannot kill or neutralize them. The captured viruses remain trapped in the filter media until the filter is replaced or cleaned. Regular maintenance and replacement of the filter are necessary to ensure its continued effectiveness in capturing viruses and other airborne particles.

HEPA filters are commonly used in various settings, such as hospitals, laboratories, and cleanrooms, to help maintain clean and healthy air quality. They can be used in standalone air purifiers, HVAC systems, or specialized filtration units to filter out a wide range of particles, including viruses, allergens, dust, and other pollutants.

What does HEPA mean?

HEPA stands for High-Efficiency Particulate Air. It is a type of air filter that is designed to meet specific standards of efficiency in capturing and removing airborne particles. The term "HEPA" was originally coined in the United States during World War II when the U.S. Atomic Energy Commission needed a filter capable of removing radioactive particles from the air.

To be classified as a true HEPA filter, it must meet certain standards set by organizations like the U.S. Department of Energy (DOE) and the European Committee for Standardization (CEN). These standards define the minimum efficiency and particle size that a filter must achieve. In the case of HEPA filters, they are required to capture at least 99.97% of particles that are 0.3 microns in size.

HEPA filters are made up of a dense mat of randomly arranged fibers, typically made from materials like fiberglass. This fibrous structure creates a maze-like path for air to pass through, effectively trapping particles as they try to navigate the filter. The high efficiency of HEPA filters makes them effective at capturing a wide range of particles, including dust, pollen, pet dander, mold spores, bacteria, and some types of viruses.