Skip to main content

What are HEPA filters, and can you clean them?

HEPA filters have become an increasingly common option in smart homes for those who really, really want to make sure they’re removing every bit of allergen or potential infectious particle. Often found in air purifiers, a HEPA (high-efficiency particulate air) filter is designed to remove at least 99.97% of particles 0.3 micron in size or larger.

Such a highly efficient filter can quickly fill with clogging particles as you vacuum, which means users should be ready to regularly clean them, too. But HEPA filtration can get complicated based on the type of filter your device uses. Let’s go through the important FAQs you should know about HEPA filters in vacuums.

Are all vacuum filters HEPA?

A woman holds a Dyson V7 Allergy Cordless HEPA Vacuum.
Image used with permission by copyright holder

No, and this can get tricky. A true HEPA filter is what we mentioned above — a filter rated to capture at least 99.97% of particles 0.3 micron or greater. That’s a lot of air particles, including anything that might be dangerous like viruses, pet dander, and even the tiniest pollen particles. The catch is that few filters are actually true HEPA, and they are even rarer on home vacuums.

This doesn’t stop marketing blurbs from claiming that vacuum filters are HEPA, often using the word “HEPA” or “HEPA-like” as a catchall to insinuate, “It’s a really good filter, guys.” True HEPA filters are large and generally shaped like thick columns: That makes them rare on vacuum cleaners and more common on air purifiers that have lots of room for filters. You can find HEPA-level filtration on some larger canister and upright vacuums, usually combined with advanced sealing to trap all possible dust particles, but don’t confuse this with a certified HEPA filter.

Can you clean a true HEPA filter?

Not really. In nearly every case, HEPA filters are designed to be replaced entirely. If a HEPA filter is marked permanent, it’s almost certainly not a true HEPA filter.

HEPA filters are so efficient at filtering out particles, most of the particles they capture end up embedded deep inside the filter’s substrate. That means you can’t clean out a HEPA filter by vacuuming it, which would only take off some of the surface particles and increase the chance of permanently damaging the filter.

HEPA filters are also not designed to be washed. Washing a true HEPA filter can easily damage it so that it can no longer filter properly. Plus, the amount of particles washing it will remove will be low anyway.

How do you clean a HEPA-like filter?

Dyson Zone earcup-mounted filters.
Image used with permission by copyright holder

All right, what about vacuum filters that aren’t true HEPA but are designed to be permanent? How do you wash them? As always, it’s a good idea to read the manual and see what sort of cleaning it suggests. If it’s all right to wash the filter, then run it under cool (not warm) water with a tiny amount of detergent until the water runs clean. After that, it’s important to leave the filter out to air dry for around 24 hours, until it is entirely dry. Otherwise, a little moisture could cause mildew problems when the filter is put back into the vacuum cleaner.

If your HEPA-like filter or true HEPA has a pre-filter to trap larger particles, you should always take these out and wash them every few months. Pre-filters are sturdy, and almost always designed to be permanent, so frequent washing won’t hurt them.

When do you need to replace HEPA vacuum filters?

When to replace a HEPA vacuum filter can vary based on use. Generally, HEPA filters in residential use can last two to three years before they need to be replaced. In commercial scenarios, HEPA filters are replaced every several months or so. Generic “HEPA” filters may need to be cleaned every several months too, especially smaller filters used on stick vacs and similar models. Manuals can provide more specific information. There are also signs that a filter has outlived its purpose — mildewy smells or the sudden return of allergies can indicate it’s time to look up your device model and order a compatible replacement filter.

What about robot vacuums? Do they have HEPA filters?

irobot roomba i7+ review filters.
Terry Walsh/Digital Trends

No. Although again some may use the word HEPA, robot vacuums are too small for true HEPA filtration. However, models can use high-efficiency filters that still do a solid job of capturing particles. iRobot, for example, claims that its high-efficiency Roomba filters can capture 99% of dog and cat dander.

Are Roomba filters washable?

No, Roomba filters are generally not designed to come into contact with liquid, which can damage them. However, basic filters are designed to be cleared up from time to time by tapping the filter against your trash to displace debris. The high-efficiency filters we mentioned above often need to be replaced entirely.

Editors' Recommendations

Tyler Lacoma
Former Digital Trends Contributor
If it can be streamed, voice-activated, made better with an app, or beaten by mashing buttons, Tyler's into it. When he's not…
How to clean the Roborock S8 MaxV Ultra
The Roborock S8 MaxV Ultra vacuuming.

The Roborock S8 MaxV Ultra is a highly automated robot vacuum. Capable of vacuuming, mopping, and cleaning itself after each cycle, the premium gadget lets you go for days (or even weeks) without providing any manual input. However, like all electronics, it still needs regular maintenance. And while maintenance is fairly simple, there are still a lot of tasks you'll need to keep track of.

Here's how to clean the Roborock S8 MaxV Ultra. This includes everything from checking its brushes and mops to cleaning its sensors and checking on its water reservoirs.
Check all the brushes, mops, wheels, and filters on the robot

Read more
The best smart light switch for Alexa, Google Home, and HomeKit
The Kasa app being used to control the Kasa Smart Dimmer Switch.

One of the most satisfying smart home devices to see in action are smart lights. The thrill of dimming bulbs and changing colors with an app or voice commands has yet to wear off, and it’s one of the easiest products to set up, schedule, and troubleshoot. But what if you want to add smart capabilities to an existing light fixture? If you’re dealing with a ceiling fan, sconce, or some other pre-wired bulbs, you’ll just need to invest in a smart light switch.

These web-connected products come in multiple gang box sizes, and are sold by many different companies. Not all switches are created equal though, and we wanted to round up the best options for those with Alexa, Google Home, and HomeKit ecosystems. So we’ve done just that!

Read more
What to know before connecting the Roborock S8 MaxV Ultra to your drainage system
The Roborock S8 MaxV Ultra model that hooks up to plumbing.

One of the coolest features of the Roborock S8 MaxV Ultra is its ability to connect to your existing plumbing. This allows it to automatically refill its clean water supply and drain its dirty water after each cleaning cycle. In other words, it turns the robot vacuum into a highly automated floor cleaner that needs little to no manual input.

The most demanding portion of owning this version of the Roborock S8 MaxV Ultra is installing it. Unlike the traditional model, which comes with water reservoirs and plugs into an electrical outlet, this model needs to connect to both your water and drain lines. And depending on how your home is set up, it might be more of a hassle than it's worth.

Read more