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How to Make the Most of a HEPA Filter

Manufacturers of HEPA filters claim that their products can remove all types of airborne particles, such as dust, dander, pollen, and even mold and mildew spores. While they may do just that, it is important to note that like any other type of air filter, as debris accumulates within HEPA filters, they become clogged, and as a result, their effectiveness is compromised. When they become saturated, instead of trapping pollutants and cleaning your home’s indoor air, HEPA filters will actually start to release the pollutants that are trapped within them back out into the air, thus reducing your home’s indoor air quality.

Because HEPA filters are used on so many different devices that we use in our homes, including air purifiers, vacuum cleaners, and even HVAC systems, making sure that they are properly maintained is absolutely essential, otherwise they could end up doing more harm than good. While HEPA filters can be replaced, the cost can become exorbitant; plus, finding filter replacements can be a difficult task. In order to keep costs down and to avoid the hassle that’s associated with trying to locate new HEPA filters, you may be wondering if cleaning your existing filters instead of replacing them is a possible.

While it might seem like it would make sense, cleaning a HEPA filter isn’t as simple and straightforward as it sounds. Therefore, before you pull out your HEPA filters and attempt to read them, it’s important to gain as much information as possible so that you know whether or not cleaning these filters is actually possible and worth your while.

HEPA Filter Construction

Before we explore cleaning a HEPA filter, it’s first important to understand what they are made of. Formally known as “high-efficiency particulate air filters”, HEPA filters are designed to remove airborne particles, and they are defined according to their rating for filtering particles; not by the manner in which they are made. In order to meet HEPA standards, a filter is supposed to be able to remove up to 99.97 percent of airborne particles that measure 0.3 microns (micrometers) in size. Of course, that means that airborne particles that are smaller than 0.3 microns won’t be trapped by a HEPA filter.

According to the US Environmental Protection Agency (EPA), HEPA filters are comprised of several different materials, such as:

  • Coarse glass fibers
  • Vegetable fibers
  • Animal hair
  • Synthetic (polyester, nylon, etc.) fibers
  • Synthetic foams
  • Expanded metals and foils
  • Metallic wools

Whatever they’re made of, the fibers are randomly twisted together and are compressed into sheets that are as thin as paper. The sheets are then pleated, which increases the surface area that the air passes through. The filter is then mounted onto a metal, plastic, wood, or cardboard frame. Depending on the manufacturer, other components may be added to a HEPA filter; a screen or a pre-filter that can remove larger particles, activated carbon to remove gaseous materials and odors, or chemical treatments; all of which are supposed to help to increase the amount of airborne particles that will stick to the particles.

Where Are HEPA Filters Most Frequently Used?

HEPA filters were initially made to be used in industrial and research facilities as a way to remove airborne radioactive particles in nuclear testing labs. They were so effective that they started being used in a variety of other applications and consumer products. Some of the most popular appliances and products that HEPA filters are used in include:

  • Stand-alone air purifiers
  • Whole-house air purifiers (HVAC systems)
  • Vacuum cleaners
  • Automobiles

Why Are HEPA Filters Used?

So, why are HEPA filters used in so many different consumer products? Put simply, to improve indoor air quality. On average, people spend about 90 percent of their time inside, and indoor air is up to five times more polluted than outdoor air. HEPA filters are used to combat this problem and increase indoor air quality. They’re particularly beneficial for individuals who suffer from allergies, respiratory health conditions, such as asthma and COPD, and people who have sensitive immune systems, such as the elderly and infants. Small airborne particles, such as dust mites, mold and mildew spores, pet dander, and other types of allergens and contaminants, can trigger various types of health issues, causing allergy or asthma attacks, increased wheezing, nasal congestion, and more. They can also increase the risk of respiratory illnesses, as these pollutants can act as fomites and when they become contaminated with infectious agents, those infectious agents can be spread to people.

HEPA filters in a vacuum cleaner, an HVAC system, and/or an air purifier are designed to filter out particles from the air; they are not able to remove gaseous materials, such as volatile organic compounds (VOCs), smoke, and odors. Some studies have shown that air purifiers with HEPA filtration may be able to minimize the amount of particulates in the air, and thus, they may be able to improve the air quality overall. It should be noted, however, that a lot of harmful contaminants, such as chemicals or particles that are found in smoke, are significantly smaller than what HEPA filters are capable of trapping. Additionally, there is a chance that mold growth can occur on a HEPA filter, and as such, the filter can push the contaminants back into the air. A Korean study found that mold growth can occur within HEPA filters, and that the mold spores can be released into the air.

Can HEPA Filters Be Cleaned?

So, can you clean a HEPA filter? It depends. You need to look at the filter. If it has a label affixed to it that reads “permanent” or that is not specifically labeled “washable”, then no, you cannot wash it. You can knock off any excess debris or use a vacuum to loosen and suck up excess debris with a vacuum; however, do note that doing so can damage the fibers that the filter is made of. If the fibers are damaged, a HEPA filter will not be able to effectively remove particles from the air; even if the filter looks as if it isn’t damaged.

If the fibers that a HEPA filter are stretched out or torn in any way, gaps will be created in the filter, and those gaps can be big enough for airborne particles to pass through. Additionally, the condition of the frame that holds the filter is important. If the frame or the gaskets that create a seal between the frame and wherever it is mounted are compromised, air – and the contaminants that it contains – can flow around the filter rather than through it.

If, on the other hand, a HEPA filter is marketed as “washable”, then you can try to clean it. You can either run it under water after knocking off excess dust, or you can use a vacuum cleaner to remove buildup dirt and debris, and it may still be able to function the way that it did before. Do note, however, that no standard has been set for washable HEPA filters. Moreover, no studies that involved testing how well washable HEPA filters work after they have been cleaned have been conducted.

Should You Clean a HEPA Filter?

As long as the filter says “washable”, you can try your hand at cleaning your HEPA filter. However, do be aware that the filter may not function the same as it did before, even if it is marketed as “washable”. That’s because cleaning a HEPA filter – even those that claim to be washable – can damage the fibers that the filter is made of. When the fibers are damaged, the efficacy of the filter can be compromised. As such, the HEPA filter may not be able to trap airborne pollutants as well as it did prior to being cleaned.

Tips to Improve Indoor Air Quality

HEPA filters can certainly help to improve the indoor air quality of your home; however, you might be wondering if there are other ways that you can increase your indoor air quality, either in combination with a HEPA filter or in lieu of one. Some of the different options that you can try include:

  • Remove sources of pollution; for instance, avoid smoking indoors and keep pets confined in specific areas.
  • Clean your home on a regular basis. Vacuum, mop, dust, and change linens frequently.
  • Improve the ventilation of your home by opening windows and doors, and running ventilation fans.
  • Use an air purifier, which can help to remove several types of airborne contaminants.
  • Invest in regular mold testing. Indoor mold growth often goes unnoticed, but it can cause several adverse health effects. By having your home tested by a professional on a regular basis, mold growth can be detected and corrected so that you can improve the quality of your home’s indoor air.

Contact MI&T

If you’re looking for a reliable professional indoor mold growth testing professional, contact the team at Mold Testing and Inspection. Our certified, licensed, and insured technicians use the most advanced tools, state-of-the-art technologies, and proven techniques and strategies to test the surfaces and air inside your home. With our services, you’ll be able to breathe a whole lot easier.