Solutions by situation
A home with pets: the allergen filtration actually helps with
The problem
Pet allergen behaves differently from most household allergens, and the difference decides what works.
Dust mite allergen travels on large particles that settle within minutes, so filtration catches very little of it. Cat allergen — Fel d 1 — is small, sticky and stays airborne for hours, which puts it squarely in the range where a HEPA unit does real work.
The complicating factor is persistence: Fel d 1 adheres to walls, clothing and soft furnishings and remains detectable in a home for months after a cat has gone.
What this situation actually needs
Requirements first, in the order they matter. Note that several of these are not products.
Continuous filtration in the sleeping room
Eight unbroken hours, and the allergen stays airborne long enough for filtration to reduce it meaningfully.
H13 HEPA at 4–5 air changes per hour, running continuously, door closed
A pet-free zone
Excluding the pet from one room reduces the allergen arriving there to what is carried on clothing.
Bedroom permanently pet-free, door kept closed
Reservoir reduction
Soft furnishings accumulate allergen and release it when disturbed.
Hard floors, washable covers, weekly hot washing of pet bedding
Effective vacuuming
An unsealed vacuum exhausts fine allergen back into the room, which is worse than not vacuuming.
Sealed-system HEPA vacuum
The specification
Written as a specification rather than a product name, deliberately. A specification survives a model being discontinued and can be taken to any shop; a product recommendation expires.
| Attribute | Target | Why |
|---|---|---|
| Filter class | H13 HEPA; carbon optional unless odour is also a concern | The allergen is particulate; carbon addresses smell, which is a separate complaint |
| Sizing | Room volume × 4–5 ACH | Continuous allergen generation means the unit needs to keep up rather than catch up |
| Placement | Bedroom, pet excluded, door closed, running continuously | Concentrating capacity where exposure is longest |
| Pre-filter | Washable, cleaned every two weeks | Pet hair loads a pre-filter far faster than dust alone |
| Noise | Under 40 dB(A) at the overnight speed | Continuous running is the whole strategy, and it only works if the unit stays on |
What to avoid
In every one of these situations there is a purchase that looks obviously right and is wrong.
An ioniser for pet allergen
It deposits allergen onto walls and furniture, from which movement resuspends it. That is relocation, not removal.
Buying a breed marketed as hypoallergenic
No breed is free of the allergen. Individual animals vary in production, and breed is not a reliable predictor of it.
Rehoming the pet and expecting immediate relief
Fel d 1 persists in a home for months. If it comes to that decision, expect a lag and a deep clean.
An unsealed vacuum with a HEPA cartridge
A HEPA filter in a leaky body exhausts fine allergen through the gaps. Sealed system is the specification that matters.
Frequently asked questions
Do air purifiers help with pet allergies?
Are there hypoallergenic cats or dogs?
How long does pet allergen last in a house?
Budget bands are indicative Indian market ranges for planning, last reviewed 2026-08-08. Where this page recommends a test before a purchase, that ordering is deliberate — the specification depends on the result, and a recommendation made without one is a guess wearing a table.