Mask Filtration and Breathability Data

Fix The Mask — the technical.
3 min readOct 27, 2020

Data Updated: 2/12/2021
Text Update: 01/24/2023 — test lab citation added

We’ve tested the most common masks that we could find. This is how they stack up.

Test Method

The problem with mask testing is that most testing standards have a lot of variability.

Getting in touch with the main mask testing labs during the pandemic has been a struggle. This has caused a bunch of research institutions and DIYers alike to create their own test setups. This is a problem because these different test set-ups produce results that cannot be compared side by side. A good score in a non-representative test doesn’t mean anything.

As such, Fix The Mask has chosen the most widely accepted, aggressive test method there is, the NIOSH protocol through which N95 respirators are validated.

Which metrics matter?

There are 3 criteria that matter most: Filtration, Breathability, and Fit. All three are critical to ensuring optimal mask performance. If one of these 3 is inadequate, the resultant mask is poor. We have independently validated fit with the Essential Mask Brace, and data can be found here. We have you covered.

Filtration and Breathability will be guided by the filter that you choose. We’ve tested and reported the data for some commonly available masks, shown below.

Filtration Efficiency

The ideal is to have as high a filtration efficiency as possible. N95 respirators perform between 95% — 100%.

In our tests, surgical masks (made of melt blown fabric) perform way better than any cloth mask. Why? Check out our blog post here.


This is measured by “initial resistance” in the test set-up. Anything above 135Pa is very difficult to breathe through when properly sealed, and it is not recommended wearing for a long period of time.

Source: All data was collected by 4C Air on a TSI 8130A “Automated Filter Tester”, using NaCl as the aerosol with 0.26 um mass median diameter, per NIOSH TEB-APT-STP-0059

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Consumer-available Masks

Armbrust USA
Herogard: discontinued
Safe Warrior
BYD (Costco): discontinued
Outdoor Research

Healthcare-available Masks




Fix The Mask — the technical.

The latest data and information on the Essential Mask Brace and masks in general.