You want your vacuum to catch as many allergens as possible, rather than blowing them back out into the air, which is why HEPA filters are sought after by many buyers. You might be wondering if your current Shark vacuum has a HEPA filter, or which model to buy if you want a HEPA filter.

Because some Shark vacuums have HEPA filters and others do not, it's not as simple as saying your vacuum definitely does or definitely doesn't have a HEPA filter. We have some information below to help you figure it out, plus more about HEPA filters and how they work.

HEPA is short for high-efficiency particulate air. A HEPA filter is a type of air filter that's capable of trapping at least 99.97% of particles of 0.3 microns. This doesn't mean that it can't capture particles smaller than 0.3 microns — particles smaller and larger than 0.3 microns are more likely to be captured by a HEPA filter, which is why tests focus on this size. Although some non-HEPA filters may be equally good at filtration, HEPA filters must be officially tested and certified. To get an idea of how small the particles a HEPA filter can trap are, a single hair has a diameter of roughly 50 to 100 microns, so a particle of 0.3 microns is extremely tiny and imperceptible to the human eye.

HEPA filters are placed somewhere inside a vacuum cleaner where the air sucked in by the appliance will be forced through the filter. HEPA filters generally consist of several layers — some more basic sieve-like layers to filter out larger particles, plus one accordion layer of fiberglass that's designed to trap smaller particles.

No, HEPA filters aren't essential. You can find many vacuums, including some Shark vacuums that don't have HEPA filters that perform just fine and trap an adequate amount of tiny particles to not cause issues for most users. HEPA filters are more of a draw for people who suffer from allergies to substances like dust, pet dander and pollen, since a true HEPA filter will catch the vast majority of these particles. They can also trap mold spores and some bacteria and viruses, which is a big positive.

Some Shark vacuums have HEPA filters, and some don't, so you'll need to investigate further to discover if your Shark vacuum has a HEPA filter. Below you'll find some of the different types of Shark vacuums and how likely they are to have HEPA filters.

Although not all Shark upright vacuums have HEPA filters, we've found that the vast majority do, so if you have an upright model, it's quite likely that it has a HEPA filter. The Shark Rotator Lift-Away DuoClean PowerFins Upright Vacuum is one popular model that features a HEPA filter. It has a range of other great features too, such as a lift-away canister and a self-cleaning brush roll. Another great model with a HEPA filter is the Shark Navigator DLX Upright Vacuum Cleaner, which has an effective power nozzle and a handy hose extension.

Fewer Shark stick vacuums have HEPA filters compared to upright models, but you can still find a decent number that do. The Shark IZ462H Vertex Cordless Stick Vacuum is an excellent choice as its HEPA is fully sealed, making it even better for allergy sufferers. The Shark Cordless Pet Plus Lightweight Stick Vacuum is another great option, particularly for homes with pets or high-traffic homes.

Shark produces several robot vacuums, including the Shark IQ AV1002AE Robot Vacuum. At the time of writing, none of these contained certified HEPA filters, probably due to the small space inside the vacuum to fit a filter. Some higher-end Shark robotic vacuums do contain high-efficiency filters, however, which do a great job filtering out allergens and other small particles, even though they don't have HEPA certification.

You can buy handheld vacuums from Shark for spot cleaning, cars, upholstery and more. The Shark UltraCyclone Pet Pro Plus is great for cleaning up pet hair, especially from couches and other upholstery, while the Shark WANDVAC is extremely compact and great for spot cleaning small messes. No Shark handheld vacuums currently on the market have HEPA filters, but since they aren't used as a main vacuum, the filter type isn't as important.

If you're still unsure whether your current Shark vacuum has a HEPA filter, check the filter itself. After removing the filter from your vacuum, check for a serial number and test results. These must be printed on a true HEPA filter. If the test results state that the filter can capture 99.97% or more of 0.3-micron particles, then it's a HEPA filter. If it doesn't have a serial number or test results printed anywhere on it, or the test results indicate it traps less than 99.97% of 0.3-micron particles, it isn't a HEPA filter.

Like all vacuum filters, HEPA filters need semi-regular cleaning. Once every two to three months should suffice for most households. The filter will be housed behind a removable grate or panel, though you may need to check your vacuum's user manual to locate it if you're unsure. Once you've found the filter, remove it and clean it under warm running water. Don't use soap or other cleaning products, but you can gently scrub it to remove dirt, if necessary. Once cleaned, leave it to dry in a sunny spot, and don't put it back in your vacuum until it's completely dry.

Lauren Corona is a writer for BestReviews. BestReviews is a product review company with a singular mission: to help simplify your purchasing decisions and save you time and money.

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