Fix The Mask Data —the Essential Mask Brace

Fix The Mask — the technical.
3 min readAug 11, 2020


Latest fit and filtration data for the Essential Mask Brace. Last Updated 10/19/2020

The Essential Mask Brace — now available on Kickstarter


  • According to recent statistical analysis, 75% of people need to be wearing masks that are 75% effective in order to slow the pandemic.
  • SARS-CoV-2 is spread through aerosolized particles that are emitted through activities such as breathing and talking (link, link).
  • Surgical masks alone are not adequate protection from the user inhaling aerosolized particles due to the leak paths on the sides of the mask.
  • The Fix The Mask Essential Mask Brace helps block leak paths.



The Essential Mask Brace was designed using the 3D printed heads from the NIOSH Anthropometric Data. There was no cyclic flow through our head forms during testing, but these different head shapes did help us solidify a design that works well on a variety of different face shapes.

“Surface scans and 26 three-dimensional (3D) landmark locations were collected for 947 subjects using a Cyberware 3-D Rapid Digitizer…Using anthropometric data gathered during the 2003 NIOSH survey, parameters for new headforms in five size categories were developed by the National Personal Protective Technology Laboratory (NPPTL) of NIOSH.”

NIOSH Anthropometric Heads
Passing score of 200+ on all 5 head forms with the Essential Mask Brace

Human Fit Testing

We then tested on human subjects, following the OSHA-standard ambient aerosol condensation nuclei counter (CNC) quantitative fit testing protocol.

*As of 2/7/2021 we have had 60+ passes with the quantitative fit tester, and we are in the process of compiling the data into chart format.

We are currently also collecting data with the Bitrex (Denatonium Benzoate) Solution Aerosol Qualitative Fit Test Protocol. So far we’ve had 40 individuals pass.

If you would like to add to our dataset, please reach out to us at


We found an independent lab to perform the NIOSH 42 CFR 84 procedure TEB-APR-STP-0059 (85L/min, NaCl, 0.075 micron count median diameter, 0.26 micron mass mean diameter). They created a fixture to increase the surface area of the test sample to better match what’s actually used in practice (see why here).

Find our latest dataset comparing different masks here.


The level of breathability of N95 respirators is measured by inhalation resistance and exhalation resistance. We tested a few different types of masks using the NIOSH test protocol, and found the below results. Fix The Mask does not recommend the use of cloth masks in combination with the Essential Mask Brace.

Find our latest dataset comparing various different masks here, and a separate official report from ATOR Labs below.

Next Steps

  • We will be testing more samples of the most promising surgical masks to confirm repeatability.
  • We will be partnering with different surgical mask suppliers that can guarantee a high-filtering, reliable product.



Fix The Mask — the technical.

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