Does an Air Purifier Help With Pet Hair? What It Catches and What It Can't
An air purifier helps with the smallest pet particles, the fine dander that stays in the air long enough to be pulled through a filter. It does very little for the hair you can actually see. The US Environmental Protection Agency explains that larger particles settle out of the air and onto surfaces quickly, so air cleaners are not likely to remove them. If the problem is hair on your furniture and in your carpet, a purifier won't fix it. Brushing your pet and removing hair that has already settled will.
That doesn't make a purifier useless in a pet home. It just does a different job from the one most people buy it for.
Where pet hair actually ends up
| Where the hair is | Can an air purifier reach it? | What actually removes it |
|---|---|---|
| Fine dander still floating in the air | Yes, while the unit is running | A purifier sized for the room; a clean HVAC filter |
| Loose hair still on your pet | No | Brushing, ideally outdoors |
| Settled on hard floors | No | Vacuum or damp mop |
| Walked into carpet, rugs and carpeted stairs | No | A vacuum, plus a carpet rake for embedded hair |
| On the couch, bedding, clothes and car seats | No | A rubber or electrostatic glove, a lint roller, a no-heat dryer tumble |
| Caught in vents and returns | No | Vacuum and wipe the grilles; change the filter |
Source: particle settling and air-cleaner limits per the US EPA; surface methods per the Fido Fave guides linked below.
The short version: of the six places pet hair ends up, a purifier reaches one, and it's the one you can't see.
What a purifier actually catches
A purifier can only filter what is floating past it. In the EPA's words, particles "must first be suspended in the air to be removed." Anything lying on the floor or woven into a cushion is out of reach, however powerful the machine.
The EPA sorts household particles by size. A significant share of cat and dog dander is small, stays airborne longer, and is more likely to be caught by an air cleaner. Larger particles, including a smaller share of dander, behave differently: most of them settle before they ever reach a filter. A whole shed hair is far bigger than either.
So a purifier running in a room with a shedding dog will pull in a lot of fine dander, and its filter will grey faster than in a home without pets. What it won't do is stop tufts collecting under the couch. Those were never in the air long enough to be pulled in.
If you're buying one anyway
There are good reasons to run a purifier in a pet home, particularly if someone in the house reacts to dander. A few things matter more than the brand:
Size it to the room. The EPA's advice is to choose a portable air cleaner whose clean air delivery rate (CADR) is large enough for the room. Its consumer guide sets a minimum CADR of 130 for a 200 sq ft (19 m²) room, and suggests sizing up if your ceilings are higher than 8 ft (2.4 m).
Put it where your pet sleeps, and leave it on. The American College of Allergy, Asthma and Immunology recommends running a HEPA air cleaner continuously in a bedroom or living room; the Asthma and Allergy Foundation of America says at least four hours a day. Both also advise keeping pets out of the bedroom.
Keep expectations modest. The EPA notes that the health improvements from air cleaners are typically small and not always noticeable to the person. A purifier works alongside cleaning, not instead of it.
Your heating and cooling system is a large air filter too. If you have forced air, a clean HVAC filter does part of what a purifier does, across the whole house. We walk through clearing pet hair out of vents and filters in a separate guide.
Where the hair problem gets solved
At the source. Every hair you brush out is one that never reaches your floor. The Asthma and Allergy Foundation of America even suggests having someone brush the pet outside to remove fur. It's the cheapest fix and the one that shrinks everything downstream. Our piece on less shedding starting before the brush covers how often and with what.
In the carpet. Hair that's been walked into carpet pile doesn't lift with a single vacuum pass. Our Dual-Sided Carpet Rake is made for carpets, rugs and carpeted stairs: the copper-and-rubber edge on its 11.8 in (30 cm) head drags embedded hair up into a pile you can pick up, and the handle extends to 54 in (137 cm) so you can do it standing. It's a carpet tool, not one for sofas or car seats.
On fabric. For the couch, the dog's blanket, your clothes and car upholstery, a hand tool works better than anything with a long handle. Our Reusable Pet Hair Remover Glove uses static from its Oxford-fabric face to lift hair off upholstery and roll it into strips, and it rinses clean. A damp rubber kitchen glove does a similar job on smooth upholstery if you'd rather not buy anything.
For the room-by-room version, see our guide to getting rid of pet hair in your house. If allergies are the real reason you're looking at purifiers, our piece on managing dog dander is the more useful read.
Frequently Asked Questions
Q: Do air purifiers help with cat hair more than dog hair?
A: For cat dander, a little. An allergist quoted by the American College of Allergy, Asthma and Immunology describes cat dander as the smallest dander, staying airborne for at least 30 minutes after it's disturbed. Cat hair itself still settles, and once it's on a surface a purifier won't pick it up.
Q: Will an air purifier make my dog shed less?
A: No. Shedding comes from your dog's coat, not the air in the room. A purifier only deals with what has already come off your pet and is still floating.
Q: How big an air purifier do I need for a pet home?
A: Size it by CADR to the room it will run in. The EPA's consumer guide sets a minimum CADR of 65 for a 100 sq ft (9 m²) room and 195 for a 300 sq ft (28 m²) room. Go bigger for high ceilings.
Q: Does an air purifier help with dog smell?
A: Not much. Most pet smell comes from fabric, bedding and carpet, which a purifier never touches, so that's where the cleaning has to happen.
Sources
- US EPA — Guide to Air Cleaners in the Home (https://www.epa.gov/indoor-air-quality-iaq/guide-air-cleaners-home)
- US EPA — Guide to Air Cleaners in the Home, 2nd Edition (PDF) (https://www.epa.gov/sites/default/files/2018-07/documents/guide_to_air_cleaners_in_the_home_2nd_edition.pdf)
- US EPA — Residential Air Cleaners: A Technical Summary, 3rd Edition (PDF) (https://www.epa.gov/sites/default/files/2018-07/documents/residential_air_cleaners_-_a_technical_summary_3rd_edition.pdf)
- American College of Allergy, Asthma and Immunology — Pets, Dog and Cat Allergies (https://acaai.org/allergies/allergic-conditions/pet-allergies/)
- Asthma and Allergy Foundation of America — Allergic to Your Pet? Learn About Dog and Cat Allergies (https://aafa.org/allergies/types-of-allergies/pet-dog-cat-allergies/)