> ## Documentation Index
> Fetch the complete documentation index at: https://docs.sonohealth.com/llms.txt
> Use this file to discover all available pages before exploring further.

# HEPA 14 vs. True HEPA: What's the Difference?

> HEPA 14 vs. 'True HEPA' explained: what the marketing terms mean, how filtration efficiency really compares, and why the SonoHealth AirPro's medical-grade HEPA 14 captures more.

"True HEPA" is a marketing phrase, not a strict grade, and usually refers to HEPA 13, which captures 99.95% of particles at 0.3 microns. HEPA 14 is a higher, lab-certified medical grade (EN 1822) that captures 99.995% at the same size, letting roughly 10 times fewer particles slip through.

## What does "True HEPA" actually mean?

"True HEPA" was coined to distinguish real HEPA filters from cheaper "HEPA-type" imitations. In practice, most products labeled "True HEPA" meet the HEPA 13 level: 99.95% efficiency at 0.3 microns, the most penetrating particle size (MPPS). It is a genuine HEPA filter, but it is not the highest grade available.

## What is HEPA 14?

HEPA 14 is a classification under the European standard **EN 1822**. A HEPA 14 filter must capture **99.995% of particles at 0.3 microns** in certified testing. The SonoHealth AirPro uses a medical-grade HEPA 14 filter and captures 99.9% of particles down to 0.1 microns, the same filtration class used in hospital cleanrooms and surgical suites.

## HEPA 14 vs. True HEPA: side by side

| Grade               | Efficiency at 0.3 microns | Common label                | Particles passing through |
| ------------------- | ------------------------- | --------------------------- | ------------------------- |
| HEPA-type / HEPA 11 | \~95%                     | "HEPA-type," "99% HEPA"     | 1 in 20                   |
| HEPA 13             | 99.95%                    | "True HEPA," "Medical HEPA" | 1 in 2,000                |
| **HEPA 14**         | **99.995%**               | "Medical-grade HEPA 14"     | **1 in 20,000**           |

At 99.95% (HEPA 13), 1 in 2,000 particles passes through. At 99.995% (HEPA 14), only 1 in 20,000 does, a tenfold reduction over hours of continuous filtration.

## Does the difference matter for allergies, asthma, and smoke?

For most everyday dust, the gap is small. It matters most for **ultrafine particles**, where wildfire smoke, diesel exhaust, and allergen fragments fall well below 1 micron. Higher efficiency at the MPPS means fewer of these breakthrough particles reach your airways over a day of use.

<Note>
  An air purifier reduces airborne triggers and supports cleaner indoor air, but it is not a medical treatment and cannot cure allergies or asthma. The U.S. EPA notes filtration works best alongside removing pollutant sources and ventilating. See the [EPA Guide to Air Cleaners in the Home](https://www.epa.gov/indoor-air-quality-iaq/guide-air-cleaners-home).
</Note>

## Beware "HEPA-type" and "HEPA-like" filters

Labels such as "HEPA-type," "HEPA-like," or "99% HEPA" usually indicate a filter that does **not** meet true HEPA standards, often closer to HEPA 11 (\~95%). If a purifier's filter grade or EN 1822 rating is not stated, treat the claim with caution.

## Which does the SonoHealth AirPro use?

The AirPro uses a **medical-grade HEPA 14** filter (EN 1822, 99.995% at 0.3 microns) with an antibacterial coating, backed by a pre-filter, activated carbon, and fully enclosed UV-C. It captures 99.9% of particles down to 0.1 microns, covers up to 1,200 sq ft, and runs ozone-free.

## Bottom line

"True HEPA" typically means HEPA 13. HEPA 14 is a verified step up, capturing 10 times fewer particles at the hardest-to-trap size. If you are buying a purifier for health reasons, look for a stated HEPA 14 / EN 1822 rating rather than "True HEPA" marketing alone.

***

**Related:** [HEPA 14 Filtration](/air-purifier/hepa-14-filtration) · [HEPA 14 vs. HEPA 13](/air-purifier/questions/hepa-14-vs-hepa-13) · [Best HEPA 14 Air Purifier](/air-purifier/best-hepa-14-air-purifier) · [AirPro vs. Competitors](/air-purifier/vs-competitors) · [AirPro Overview](/air-purifier/overview)