On this page
HEPA vs HEPA-type vs H13
True HEPA is a defined standard: it captures 99.97% of particles at 0.3 microns. The 0.3 micron figure is the hardest size to catch, and smaller particles are actually captured more easily by diffusion, which is why it is used as the benchmark.
H13 is a European classification roughly equivalent to true HEPA, sometimes quoted at 99.95%. Some brands market H14 (99.995%). For a nursery, H12 or H13 is entirely sufficient; anything better is a diminishing return on particulate you will not measure. Related reading: the air quality guides.
“HEPA-type” is not a standard. It means a filter of some efficiency that the manufacturer has declined to certify. It may be fine, but you have no basis for comparison, and in a nursery there is no reason to accept the ambiguity. Our HEPA vs carbon explainer covers how the two stages divide the work. the newborn-safety guide covers this in more detail.
What a nursery actually needs
A true HEPA filter, correctly sized for the room, is the substance of it. Everything else is support. The particle sizes that matter in a nursery — pollen, dust mite debris, pet dander, smoke particulate — sit squarely in the range HEPA is designed for. For the full breakdown, see the Blueair nursery guide.
What you do not need is an ioniser or any ozone-producing stage. Ozone is a respiratory irritant with no place in an infant room, and there is no safe reason to add it. Our ozone-free explainer covers how to spot it on a box and non-toxic units covers materials more broadly. If that is your situation, the Coway nursery guide walks through it.
Sizing matters as much as the filter grade. A genuine HEPA filter in an undersized unit running flat out delivers fewer air changes than a good filter in a correctly sized one — see air changes per hour.
The three layers and what each does
A washable pre-filter catches hair, lint and large dust. It protects the HEPA layer, and vacuuming it monthly is the cheapest maintenance you can do. Some units embed a thin carbon pad here.
The activated carbon layer handles odours and some volatile organic compounds — cooking smells, pet odour, off-gassing from new furniture. It is not a particulate filter and it does not substitute for HEPA.
The HEPA cartridge does the particulate work. It is the layer that justifies the purchase, and it is the one to check for a real certification. Our filter cost guide shows how these three layers drive the running cost.
Marketing claims to ignore
Four phrases that mean nothing specific: “HEPA-type”, “HEPA-like”, “99% filtration” without a particle size or standard, and “medical grade”. None of them is a certification, and all of them are common on cheap units.
Also ignore “removes 99.9% of viruses” style claims unless a specific test standard is named. Air purifiers do reduce airborne particles that can carry pathogens, but the sizeable claims are usually about a filter test, not a room outcome.
The one claim worth trusting is an AHAM-certified CADR number, because it is independently verified and it tells you how much filtered air the unit actually delivers — see what CADR means.
How to verify the filter you are buying
Check the product page for the words “true HEPA” or “H13” next to a stated efficiency figure. Check whether the replacement filter listing also says true HEPA, because that is what you will be buying for years, not the original.
Look at the filter photograph. A real HEPA cartridge has dense pleated media; a thin sheet of fibrous material in a frame is not HEPA. The pleat depth is also a rough proxy for media area and therefore filter life.
Check that third-party replacements exist and are described as HEPA grade. If the only option is a proprietary cartridge at a premium, factor that into the three-year cost — see the replacement guide.
Replacement and cost
HEPA cartridges typically need replacing every six to twelve months, more often with a pet or a dusty apartment. Carbon layers go sooner, around every three months, because they saturate silently.
Vacuum the pre-filter every two to four weeks. That single habit is the difference between a filter that lasts twelve months and one that lasts six. Our baby-room filter schedule has the full routine.
Budget on the filter cost, not the purifier price. A cheap unit with a $50 proprietary filter can cost more over three years than a mid-range unit with a $20 third-party cartridge — the arithmetic is in filter cost per year.
Filter grades compared
| Label | Is it a standard? | Efficiency | Good for a nursery? |
|---|---|---|---|
| True HEPA | Yes | 99.97% at 0.3 microns | Yes — the baseline |
| H13 | Yes (EN 1822) | ~99.95% | Yes |
| H14 | Yes (EN 1822) | ~99.995% | More than needed |
| HEPA-type | No | Unstated | No — no basis to compare |
| 99% filtration | No | Unstated particle size | No |
Sources: U.S. EPA (Residential Air Cleaners guide; ozone generator warning), AHAM (CADR certification program), EN 1822 (HEPA classification), ASHRAE Standard 62.2.
Frequently asked questions
What HEPA grade is best for a nursery?
Is HEPA-type as good as HEPA?
Do I need a carbon filter in a nursery purifier?
How can I tell if a filter is real HEPA?
Is an ioniser safe in a nursery?
Related guides
