How to Clean and Reuse a HEPA Filter

Most of the best HEPA air purifiers for babies and newborns as well as those for everyone else use non-washable, disposable air filters. But filter replacement costs can add up to a pretty penny real quick. Fortunately, some baby air purifiers use permanent, reusable washable air filters. You probably own a unit with a washable filter. And I guess that’s why you’re here seeking to learn how to clean and reuse a HEPA filter.

Or maybe you own a non-washable filter air purifier but still wonder whether you can rinse its permanent air filter at the faucet. Perhaps you’d also like to know if vacuuming or air-compressing this kind of filtration media works better than washing it. This post addresses all these critical questions and more.

Without further ado, here’s how you should wash or vacuum-clean a HEPA filter. But first off….

Understand Whether Your HEPA Filter Is Washable/Vacuumable

Carefully read the manufacturer’s manual and learn whether the HEPA filter can actually be washed or vacuumed. There are tons of air purifiers with permanent, washable filters on Amazon and lots of other locations online.

Honeywell provides some of the most virile air purifiers with a permanent filter. Lots of reviewers (including yours truly) can’t stop preaching about the awesomeness of the Honeywell HFD-120Q or its smaller sibling the Honeywell HFD-010.

These devices work pretty well, but they’re not real HEPA air filters. Rather, they use the much-praised HFD filter which some claim performs even better than a True HEPA filter. But I’ll say it again: HFD filtration technology and all other indoor air purification technologies fall short of the HEPA Standard.

But some HEPA (usually HEPA-Type) air filters are non-washable. These ones can be vacuumed but most are usually disposable. In most cases, these air filters should be replaced every couple months (or years in some instances).

Do not under any circumstances rinse a non-washable HEPA filter under a faucet. Giving a non-washable permanent filter a rinse no matter how quick harms it.

What If You Can’t Find Your Air Purifier Manual?

Maybe you didn’t for some reason get the user manual or you somehow misplaced it. Now what? Not to worry.  Instead, ask your preferred search engine. Open your browser and type in X air purifier manual. You should get the digital version of the care and maintenance instructions in no time.

Step-by-step Guide to Washing a HEPA Filter

First, decide where you’ll do the air filter cleaning job. If the filter is rather small and you can clean it without releasing tons of dirt back into your indoor environment, clean it at the sink.

You can also do the job in your garage if you like. But wherever you choose to do it, be sure you can easily access water. Maybe you can transport water to the spot using a garden hose?

What if the filter media is extremely dirty? What if the filter is all gunked up with dirt, debris, and all kinds of filthy pollutants? In that case, it’s best to clean it outside.

Do you have asthma, COPD, or some other breathing challenge? If yes, I’d advise you to not handle the task yourself. Instead, get someone to do it for you, maybe your spouse or someone else.

We are about to clean a washable, permanent filter for your baby air purifier or for your faithful and hardworking HEPA vacuum cleaner.

Steps to Follow When Washing a HEPA Filter

Here’s the step-by-step process to follow.

Method 1: Wash the

Step 1: Take the Filter Out of Its Compartment

Turn off the baby air purifier or whichever other air purifier you have. Next, disconnect the home appliance from the power supply.

Then, proceed to take off the canister that contains the filter, in the case of a vacuum cleaner. For a purifier, open the cover to the filter chamber and remove the filter/filters.

If the HEPA is part of a 3-in-1 filtration system (a cartridge-type filter), simply grab it and uproot it from the filtration chamber. Most purifiers have a cartridge-type filter. But with others, you’ll have to remove each filter (prefilter, HEPA filter, and activated carbon filter) one after the other. Some filters are pretty easy to access while others may require a bit more time (and work) to pull out.

Step 2: Shake the Filter a Little to Release Debris and Dirt

Now, it’s time to shake off some of the dust and debris. If it’s been a while since you last cleaned the filter, it’s probably all clogged up. It’s buried in dirt and filth.

Walk over to the trashcan and give it a few light taps with the filter. That loosens the unsightly debris and dirt that’s built up over time. Get all the dirt into the trashcan, not onto the floor or into the sink.

Step 3: Turn On the Faucet or Garden Hose

Turn on the faucet and hold the filter under the stream that gushes out of it. Keep moving the filter or hose around so that every area receives adequate attention. Also, make sure to not use excessive water pressure. Otherwise, you’ll degrade the filter.

Another thing to keep in mind is what manufacturer recommends as the best water temperature for the particular filter you’re cleaning. While some companies recommend using cold water, others recommend lukewarm water.

Very important: If the filter you’re washing features a cylindrical design, be careful not to get the inner side wet. Direct the hose or faucet to the exterior of the filter.

But if the filter has a flat, rectangular shape, you can safely wet both sides. You know the filter is clean when the water starts running clear.

Step 4: Dry Out the Filter and then Reinstall It

Place the filter on some surface (maybe a table) and let it dry out completely. How long should you dry a washed HEPA filter?

Some experts say dry it for 24 hours. I’d say it depends on what the day’s temperatures look like. To prevent dust from covering my drying filter, I place it inside a wooden box I made for that purpose. The box has an open top side (wind rarely blows from the top, right?). I put the box over the filter (the box’s bottom is open, too) so that its four sides prevent dust and debris from reaching my filter.

Finally, re-insert the air filter into the chamber and turn on the machine.

*If the appliance uses a washable prefilter, give it a quick rinse under the faucet. I assume they’re washable since most are, but always consult your manual. Have the filters dry out thoroughly before re-installing them.

How to Vacuum a HEPA Filter

Another way to clean a HEPA filter, especially a non-washable one, is to vacuum it. But this cleaning method applies to pretty much every type of filter. Still, I encourage you to follow the manufacturer’s advice in every situation.

Here are the steps to follow when vacuuming a non-washable HEPA filter.

1. Step 1

Shut down the home appliance and keenly follow the manufacturer’s instructions to remove the filter(s). With a few exceptions, you usually won’t need help accessing and removing the filter cartridge or canister from the unit.

Step 2

Grab your vacuum cleaner (preferably one with a HEPA filter). Then, direct the vacuum’s nozzle over the filter. Maybe your vacuum features a brush attachment instead. Run the attachment as you would a nozzle, that is, vertically from the filter’s top to the bottom. Remember: it’s not uncommon for people to ruin their filter by poking them with the nozzle. So, be extra careful when using a vacuum.

Step 3

Run a garden hose or faucet over the prefilter or charcoal filter for a couple minutes (about 2 minutes). Only stop when the water starts running clear. Then, put these filters in a clean place and let them dry out completely.

Step 4: Correctly Reinstall the Filters

Get the HEPA filter back into the device along with the washable ones if the unit uses such. Be sure to click the filters back into place the right way. Otherwise, the unit just won’t function properly. Next, plug the filtration system back in and fire it up to enjoy clean, crisp air.

Additionally, remember to reset the clean filter indicator where applicable after you reassemble the air purifier.

Use an Air Compressor to Clean Your Filter

You can also use an air compressor to clean a HEPA filter. Simply grab the compressor and use it like you would a vacuum. Follow the same procedure we used when vacuuming the filter above.

Creating a Problem to Solve a Problem?

It seems to me like using an air compressor or a vacuum cleaner to clean a HEPA filter is like creating a problem to solve a problem. In the end, you have a dirty filter inside of the vacuum or air compressor that may need cleaning or even replacement soon.

How to Maintain a HEPA Filter

Here’s what to do if you want your air purifier functioning at peak performance.

·Periodically Remove the Filter and Inspect It

HEPA filters aren’t cheap. So, it makes perfect sense to show them some love consistently. It’s critical to check the filter regularly to decide whether it needs a quick rinse or vacuuming.

·Regularly Monitor the Clean Filter Reminder

Also, be sure to check the electronic clean filter indicator if your air purifier has it. But what if my device lacks the clean filter indicator?

As a general rule, clean your washable HEPA filter every 3-6 months. At least, that’s what most manufacturers recommend.

But each allergy sufferer’s situation is different. What works for my indoor air pollution situation may not necessarily work for you. Most reviewers say to clean a HEPA filter every month. Generally, the dustier your indoor environment, the sooner your filter needs cleaning – or replacing.

Oh, there’s no problem if you clean a filter earlier than the manufacturer’s recommendation. You can choose to clean it before the indicator light comes on if you deem it necessary.

·Replace Underperforming HEPA Filters

Vacuum-only HEPA filters and washable permanent ones tend to outlast disposable filters. However, no air filter lasts forever no matter how permanent it may be. Over time, a device’s air cleaning capacity wanes no matter how religiously you stick to the filter cleaning schedule.

But how do you know that a filter has outlived its usefulness? Here’s a simple test. Place a hand over the air outlet when the machine is running on high. If it feels like the airstream blowing out is weak-ish even after cleaning the filter, it’s time to replace your HEPA filter.

Additionally, if you’re beginning to notice dust on surfaces even after the purifier has been operating for hours, the filter clearly needs to be replaced.

So, Can You Wash a HEPA Filter?

You can wash a HEPA filter by rinsing it under the faucet if you so wish. However, that’s rarely a good idea. Real tests measuring the efficacy of HEPA filters after giving them a rinse at a faucet consistently show that washing these allergen removers is a bad idea.

Someone conducted a series of tests designed to assess how well HEPA filters clean the air after being washed or vacuumed. Well, the person that ran the tests isn’t me. But they sure come with tons of credibility. Otherwise, I’d never ever endorse or report their “research” and its findings on this baby products review site.

The testing lab in this small study belongs to an air quality improvement expert with vast knowledge of this all-important subject. The findings of the study clearly show that cleaning HEPA filters with water isn’t a smart way to save them. So is vacuuming them. More about this down the road.

Not everyone agrees on precisely what to do with dirty HEPA air filters…..

Opinion Remains Divided On How to Clean a HEPA Filter

The internet groans under the weight of myriads of opinions pertaining to whether HEPA filters should be washed or vacuumed at all.

A bunch of self-proclaimed experts out there teach that one can wash a HEPA filter at the kitchen sink to prolong its usefulness. But is that sound advice? I’ll let the findings from the small study I referred to above answer that.

Other experts — probably the type that oppose pretty much everything — assert authoritatively that you should NEVER clean a HEPA filter. They support their claim by arguing that washing this type of filter demotes it to uselessness.

For this camp, the best way to make sure your filter keeps capturing allergen triggers consistently is to replace it with a brand-spanking-new air filter. But are the proponents of this school of thought right? We’ll see.

Then there are those that believe that banging the dust and other air pollutants out of the filter is the way to go. Others convincingly state that the smartest method of resuscitating dead HEPA filters is by vacuum-cleaning them. But does shaking and banging dust and other particulates out a reliable way of re-vitalizing clogged HEPA air filters? The research answers that, too.

But before I move forward any further, I must explain a key term I see lots of people confused about: HEPA vs HEPA-type filters.

What’s a HEPA Filter and How Does It Work?

Now, let’s discuss what HEPA air filters are and what benefits they offer, if any. HEPA filters are mechanical filters that take out air pollutants by trapping them through numerous micro fibers.

A motor forces polluted air packed with bacteria, animal dander, pet hair, human skin flakes, pollen, dust mite feces, and mold spores through this filter. And as the air passes through, particulate matter remains trapped in the rather intricate fibrous network.

To increase its surface area and particle filtration power, a HEPA filter is folded many, many times, forming tons of pleats. That’s why these air filters are so effective at removing health-threatening airborne particles that stay suspended in indoor air in every American home.

According to the U.S. EPA (Environmental Protection Agency), no air filter can be called a True HEPA filter unless it can take out at least 99.97% of sub-0.3 micron particles from the air. But I don’t want to create the impression that a true HEPA filter ONLY removes microscopic particles in the 0.3 micron range.

What’s a HEPA Filter Made of?

Maybe you’ve wondered at some point: what are HEPA filters made of? HEPA air purifier manufacturers use a variety of materials to make HEPA filters. Some of the materials used to produce HEPA filters include synthetic fibers (usually durable polyester or nylon) and artificial foam. They also use vegetable fibers, animal hair including metallic wool as well as fiberglass.

The producer then compresses the filter material in question, ending up with sheets that look pretty much like pleated paper. These paper-like sheets are pleated mainly to multiply the overall surface area, making the final product excellent at stopping air pollutants.

Then, the sheets are cut up into air filters of varying sizes that go into air purifiers of different dimensions and filtration capabilities. Manufacturers devise ways to make the filter easy to use. One of those ways is mounting the filter onto a frame.

The filter frame can be made from various materials including cardboard, wood, plastic, or even metal. But I’d say I’ve seen plastic frames more often than I’ve seen any other material.

What Makes a HEPA Filter Special?

So, why can’t the entire world and their grandma stop talking about the HEPA standard? It’s because there’s something truly special about True HEPA air filters.

Unlike other effective but not excellent air filtration technologies used in competing devices, HEPA purifiers are incredibly good at capturing 0.3 micron particles and extremely small particles. The EPA in fact says that HEPA filtration has an easier time removing particles smaller than 0.3 microns in size.

So, these air filters eliminate the smallest particles (PM2.5/ultrafine particles) just as easily as they do the largest particles (PM10/course particles). What’s the conclusion here? It’s that HEPA filtration is the best protection against PM2.5 airborne particles.

My previous post Do HEPA Baby Air Purifiers remove PM2.5? amounts to an even more comprehensive answer as to whether these filters really capture ultrafine particles. And yes, air purifiers that use HEPA air filters are safe for babies, provided they’re not using ionization to clean the air. At least, the ionizer should be optional.

HEPA Filters vs HEPA-Type Air Filters: What’s the Difference?

At this point in your learning journey, I intend to shine some light on a critical matter. It’s about the difference between real HEPA and HEPA-like air filters.

If you lack an eye for detail, chances are high someone might end up delivering a fake HEPA filter pretending it’s the real thing. Be wary of anyone who says that the filter they’re hawking works pretty much like a True HEPA air filter.

A salesperson or marketer may say all they want, but remember: their air filter just isn’t a True HEPA filter. If someone says their HEPA filter captures 99.00% of pet dander, dust, mold spores, and other allergy triggers with a diameter of 2 microns or larger, they’re not selling a True HEPA filter.

They just want you to buy filtration media that works OK but not as well as a real HEPA filter while making you feel like you’re getting the real deal. If that happens to you and the person is sitting across the desk facing you, tell them to take a hike. Or slap them really hard and tell them you did that because they’re a despicable, classless liar. Just kidding.

Other Filters: Prefilter and Activated Odor Filter

Here’s a critical fact about HEPA filters. HEPA filters do not remove odors/bad household smells. Nor do they remove indoor air pollutants of a gaseous nature including wildfire smoke, tobacco smoke, paint fumes, kitchen cooking fumes, and Volatile Organic Compounds such as formaldehyde.

But tell you what? Many HEPA air purifiers actually remove odors of different kinds as well as wildfire smoke, marijuana smoke, cigarette smoke, and VOCs. How so? Because most HEPA air purifiers don’t exclusively use HEPA filters to complete the air filtration job. Instead, these air purifying devices come with other kinds of filters that make work for the main filter easier and more comprehensive.

The additional filters may include a prefilter or prefilters in some cases as well as activated carbon filter (filters in some cases). Note that some baby room air purifiers may come with more than one prefilter and carbon filter. The Medify MA25 is one such example.

The prefilter does the initial and extremely important job of capturing a variety of PM10 particulates, or relatively large particles. I’ve seen quite a few air purifiers that lack a prefilter(s). But I’d be wary of a unit like that since that often means that the device’s main filter automatically becomes a workaholic.

The main filter in a prefilter-less purifier does a lot more filtration work than it would if there was a prefilter. That means you’d end up buying replacement filters more frequently with such a deal. And you still have that money-saving goal needed to achieve financial freedom soonest possible, remember?

Then there’s the odor filter. This is a specialized air filter that puts tons of active carbon to work during air purification, eating up smoke and odors quite effectively. Of course, not every air purifier removes smoke and VOCs as well as others. Typically, the amount of active carbon packed into the smoke filter determines its overall efficiency.

Should I Wash My HEPA Filter?

Now, I present the results from the experiments the researcher conducted. One of the most critical findings from the mini-study is that washing a HEPA or even a HEPA-type filter substantially decreases its air purification power. It really doesn’t matter whether the product manual says you can wash it or not.

Some air purifiers such as the Honeywell HFD-120Q are marketed as having a washable filter that can be cleaned with water. I know at least 3 people in my social circle that wash their baby’s air purifier filter like once or twice each month. And for these parents, a washable filter purifier works as well as any. Well, that’s anecdotal evidence, and it’s what it is.

I, too, have used this purifier, the Honeywell HFD-120Q. And, I can say the product performs relatively well for a unit that uses reusable air filters. But again, that’s anecdotal evidence. The experimental data extracted from the air cleaning efficiency study proves the contrary, though, that washing filters immensely ruins them. So, make up your mind about what type of filter to use for the nursery, mom.

Washing a HEPA Filter ALWAYS Ruins It

According to the results from the small study, washing a HEPA is always a bad idea. The numbers from the experiment clearly indicated that washing the filtration media reduces its clean air delivery rate by a staggering 32%! Let that sink in — 32%. Evidently, there’s no point of washing this type of air filter if that’s what washing it does to it.

Below is a graph that illustrates what happens when a HEPA filter is washed:

washing hepa filter not OK
Data and Image Source:

Is Vacuuming a HEPA Filter Better Than Washing It?

Surely, vacuuming a HEPA is better than washing it, huh? Well, not quite. Admittedly, vacuuming a HEPA filter may be a better filter maintenance practice than is washing it. But real tests have shown that vacuuming isn’t the perfect solution for getting used filters back into shape. At least, vacuuming a HEPA filter isn’t the most ideal strategy if you desire squeaky clean air all year round.

The researcher I mentioned earlier found that vacuuming a HEPA filter may help a little since it increased the device’s Clean Air Delivery Rate by about 10% on average. In some of the instances, vacuuming did nothing as far as improving the filter’s effectiveness. In fact, vacuuming actually caused more harm than good some of the time.

While a vacuum suctions dust and other particles off the filter, it can also end up ruining the fiber structure. Look at the Hepa filter efficiency data below and see what vacuuming can do to your filter in some situations.

vacuuming marginally improve hepa filter efficiency
Image and data Credit:

As you can see below, the fibers loosen up considerably. And some of the fibers might get blown back into your home when you’re running your device.

a dirty hepa air filter
Image Credit: Look at what suctioning dirt and debris off does to a HEPA filter.

Conclusion: While vacuuming a HEPA filter may be somewhat better than rinsing it under a faucet, it doesn’t help restore the clogged up media back to its initial filtration credentials. In the end, there’s no running away from buying replacement HEPA filters for people who want allergen-free indoor air.

Don’t Pay an Arm and a Leg for Replacement Filters, Though

Fact: Replacing HEPA filters every few months ALWAYS translates to better filtration performance than  washing or vacuuming them. And reading baby air purifier filter replacement reviews can help save a few bucks over time.

While pricier HEPA filtration media generally outperforms the cheapest alternatives, it’s fallacious to think that the pricier the replacement filter for a baby room purifier the better quality it is.

You don’t want to end up tossing your little one’s device in the attic or basement because you can’t afford the $300 replacement filter it uses.  So, be sure you can afford the replacement filters right from the get-go.

How to Clean and Reuse a HEPA Filter: Conclusion

In the end, HEPA filters weren’t created to be washed or vacuumed for that matter. Rather, this filter type was designed to be disposed of after the recommended duration. It was created to serve the user really well for a couple months before replacing it with a clean set of air filters becomes absolutely necessary.

Ok, I get it. Nobody enjoys shelling out for a new set of replacement filters.  Plus, many people these days seem to be laser-focused on retiring early after achieving financial freedom. And buying HEPA replacement filters every 6 months isn’t the quickest route to massive savings.

Not surprisingly, most allergy sufferers and everyone else that craves roomfuls of disinfected air would rather wash, vacuum, or just bang dirt out of their filter. But here’s a little fact that needs to get ingrained in your mind: replacing a HEPA filter will always be better than cleaning it.

Author: Esther Moni

I'm Esther Moni, a proud stay-at-home mom and a psychology graduate of the United States International University (USIU) . I hate it when anyone calls me a housewife, because what does housewife even mean? Being a mother of two babies and a pup, Bailey, as well as being Ricky's wife tires me to no end, but I still manage a smile at the end of it all. And when my boys aren't done doing mischief, I juggle writing a post on parenting or baby gear performance for this blog and running my little counselling office based out in Nairobi. <a href="">Visit my Facebook profile here</a>, and this is my <a href="">LinkedIn profile</a>, and here's my <a href="">nascent youtube channel.

Esther Moni

I'm Esther Moni, a proud stay-at-home mom and a psychology graduate of the United States International University (USIU) . I hate it when anyone calls me a housewife, because what does housewife even mean? Being a mother of two babies and a pup, Bailey, as well as being a wife tires me to no end, but I still manage a smile at the end of it all. And when my boys aren't done doing mischief, I juggle writing a post on parenting or baby gear performance for this blog and running my little counselling office based out in Nairobi. Visit my Facebook profile here, and this is my LinkedIn profile, and here's my nascent youtube channel.