Practically anyone can benefit from using a HEPA filter. However, smokers, people with allergies, and those with advanced respiratory tract diseases, such as asthma or chronic obstructive pulmonary disease (COPD), will experience the greatest rewards, as they are particularly sensitive to air pollutants. When it comes to air purification, it is essential to understand the difference between HEPA filters, true HEPA, HEPA type, and other types of HEPA filters. To be considered a true HEPA filter, it must meet a specific standard and be tested.
These filters have been assigned a serial number and have been proven to capture at least 99.97 percent of 0.3 micron particles. It is important to look for the test results, as they must be printed on the filter. True HEPA filters may be more expensive than other HEPA filters, but they must meet a certain standard to receive the distinction of true or absolute HEPA. The American Society for Testing and Materials (ASTM) created a specific test to measure the efficiency of vacuum cleaners with HEPA filters.
However, just because a filter or vacuum bag says HEPA does not mean you are getting true HEPA performance. The Institute of Environmental Science and Technology (IEST) created a standard way of performing tests to ensure that a filter complies with the HEPA standard, although the EST notes that it is “a basis for agreement between customers and suppliers”. It is important to note that a HEPA vacuum cleaner is designed to meet HEPA standards and can be a bagged or bagless model. In addition to capturing 0.3 micron particles, the carbon prefilter also captures smoke, odors, harmful gases, and volatile organic compounds (VOCs), which HEPA filters cannot trap. These considerations about HEPA filters are essential if your goal is to reduce viral transmission by aerosol. Although there are different grades of HEPA filters, the term “True HEPA” does not refer specifically to any of them.
However, we do not recommend washing HEPA filters, even if they are intended to be reused, as the washing process can cause minor damage to the filter, reducing its effectiveness over time. The IEST did not specify any contaminants, but the industry has used a specific type of aerosol oil for much of the history of HEPA filters. It is also important to understand that just using a HEPA-type bag or adding a HEPA filter to a standard vacuum does not mean you will get real HEPA performance. Many filters sold as HEPA can capture only 85 to 90 percent of all particles, and that percentage may decrease even more for particles that are one micron or smaller. In conclusion, practically anyone can benefit from using a HEPA filter. However, smokers, people with allergies, and those with advanced respiratory tract diseases will experience the greatest rewards.
To be considered a true HEPA filter it must meet a specific standard and be tested. It is important to look for the test results as they must be printed on the filter. True HEPA filters may be more expensive than other types of filters but they must meet a certain standard in order to receive the distinction of true or absolute HEPA.
