As an expert in the field of air quality, I have been asked countless times about the effectiveness of air filters. With the increasing concern over air pollution and indoor air quality, many people are turning to air purifiers as a solution. But do these devices actually work? In this article, I will delve into the research and provide you with the truth about air filters. While air purifiers may not have an immediate impact on a person's health, studies have shown that these devices can help reduce exposure to harmful pollutants, which can have long-term health benefits. This is crucial because according to the Environmental Protection Agency (EPA), the concentration of air pollutants indoors can be two to five times higher than outdoor concentrations.
The EPA also states that a well-functioning HVAC filter can help filter indoor air when outdoor air quality is poor. At my company, we measure the effectiveness of an air filter in removing dust, pollen, and smoke from the air. We also check the airflow through the filter at different fan speeds and calculate the annual cost of replacing filters based on the manufacturer's recommendations. It's important to note that prices may vary depending on the retailer and buying filters in bulk may be more cost-effective. About a decade ago, manufacturers started incorporating more folds into air filters to increase their surface area. The EPA, ASHRAE, and CDC recommend upgrading air filters to achieve the highest possible efficiency that is compatible with your system and ensuring that the filter is properly installed to minimize air deflection through it. As air passes through the filter, pollutants and particles are captured, and clean air is released back into the living space.
In large buildings, air conditioning systems typically filter the air before distributing it throughout the building. If you have a large building, consider upgrading your air conditioning filters (consult an HVAC professional for guidance).Several studies have shown that well-constructed home air purifiers can be just as effective as commercial air cleaners in reducing airborne particles, including viral particles. However, if this is not feasible for your home, a HEPA air filter can still reduce smoke particles and be a better alternative than not using anything at all. The most effective option for filtering particles is a device with a HEPA filter, which is designed to capture at least 99.5% of particles in the air that are 3 microns or smaller in size. According to materials published by the EPA, reducing common sources of pollutants and increasing fresh air flow in the home are crucial strategies for reducing air pollution risks, and a good air purifier can help with the rest. Some filters are reusable and washable, but they require meticulous maintenance and are not typically found in the most effective air purifiers.
However, a good air filter can keep your central air conditioner (and furnace) running at full capacity by protecting the mechanical components from dust and dirt. Air purifiers that use HEPA filters can capture particles of SARS-CoV-2, the virus that causes COVID-19. To filter gases, you should choose a portable air filter with an activated carbon filter or another filter specifically designed to remove gases. Ultimately, it all depends on what you want an air purifier to do in your home and how well you choose one that aligns with your goals. A review of research has concluded that air filters have little significant effect on dust mite allergens because these allergens are deposited in larger particles that settle quickly on surfaces and are not trapped by air purifiers.