3D-printed masks a good alternative to N95 respirators

Reusable 3D-printed respirators offer a cost-effective alternative to N95 masks in providing protection against respiratory pathogens, such as SARS-CoV-2, suggests a recent study. In addition, fit testing results show that some 3D-printed mask designs appear to exceed the fit of N95 masks.

“One of the best methods for protection against respiratory diseases is the use of an N95 mask,” the authors said. “Supply shortages have demonstrated a significant need for effective alternatives to N95 masks.”

This study adjusted the designs of three of the most popular 3D-printed respirators to allow for the Occupational Safety and Health Administration (OSHA) quantitative fit testing that disperses saline into the ambient air and determines concentrations within the mask during multiple trials.

Five volunteers carried out standardized fit tests of these masks, as well as an N95 and a KN95. The authors then compared the results.

Low poly COVID-19 face mask respirator, one of the 3D-printed respirators tested, achieved a fit factor >100 in each trial. This signified a sufficient fit based on OSHA protocols. In contrast, the N95 mask achieved a sufficient fit in 60 percent of the trials, whereas none of the other masks demonstrated a suitable fit factor reliably according to the OSHA fit test.

No change in fit factor was observed in other trials when different 3D-printable plastics were used or when a widely available high-efficiency particulate air filter was used.

“Benefits of 3D-printed respirators over N95s include reduced cost and ease of production, widespread availability, reusability/sterilizability, and customizability,” the authors said.