Fix The Mask Data — V1.0, V2.0

Latest fit and filtration data for V1.0 and V2.0. Last Updated 5/24/2020

Fit Data

There are two ways to validate mask fit that are widely used in hospitals. The first if the Saccharin/Bitrex Test, which involves shoving your head in a bag while an unpleasant gas is released — if you can smell the gas, you fail. An alternative method is a quantitative metric called a Porta Count Pro. We use a Porta Count Pro to validate the fit of our designs.

The rating system goes from 0 to 200+, anything over 100 is a passing score for an N95 mask according to OSHA. “The test subject shall not be permitted to wear a half mask or quarter face piece respirator unless a minimum fit factor of 100 is obtained” (OSHA)

V1.0 DIY Mask Brace

Publication here: https://medrxiv.org/cgi/content/short/2020.05.18.20099325v1
https://onlinelibrary.wiley.com/doi/epdf/10.1002/emp2.12335

Performed by: University of Iowa, Carver School of Medicine
Study: Assessing fit of the surgical mask brace using the PortaCount Pro+
Status: Submitting for publication
Principal Investigator: Daniel Runde, MD, MME, Clinical Associate Professor of Emergency Medicine

V2.0 Mask Brace

Performed by: Independent Study

V2.0 Mask Brace + Cushions

Performed by: Independent Study

Cloth is not good enough

Filtration Research

• ASTM standard for Surgical Masks, F2100, ensures surgical mask material has a particle filtration efficiency of 95% or above.
• CDC/NIOSH 42 CFR 84, the method for testing N95s, test guarantees a filtration efficiency of 95% or above.

Research Papers

• “one electrostatic surgical model in this study and one dust mask model tested in the previous study (Rengasamy et al. 2008) obtained from different manufacturers, showed <5% penetration level when tested similar to NIOSH respirator certification test conditions at 85 liters/minute flow rate.” (source)
• “The number of particles penetrating through the faceseal leakage of the tested respirator/mask far exceeded the number of those penetrating through the filter medium.” (source)
• “Most of FLTF ratios were >1, suggesting that the faceseal leakage was the primary particle penetration pathway at various breathing frequencies.” (source)
• “suggesting that the face seal leakage was the primary particle penetration pathway for the tested FFR/SM at various breathing frequencies.” (source)
• A filtration test was performed comparing N95s to surgical masks to sealed surgical mask on a mannequin head. The sealed surgical mask was created by taping the mask to the head. “All versions of the sealed [fitted] face mask were as effective as the N95 with insignificant differences after sealing” Skaria, S. (2014).
• More papers

Next Steps:

• Determine which brands of surgical masks/filtration materials pass 42 CFR part 84.