Reusable N95 Face Mask is Easily Sterilized

Researchers at MIT and Brigham and Women’s Hospital have developed an N95 face mask made from silicone rubber, which is reusable and is easily sterilized.

The researchers hope that the mask could help with the response to the COVID-19 pandemic, as masks are in high demand and supplies are low.

The COVID-19 pandemic has seen a huge demand for personal protective equipment (PPE). This is particularly important for healthcare staff who may be exposed to COVID-19 patients on a daily basis. However, as lockdowns in various countries wind down, there is an increasing need for PPE for public use, to help prevent transmission as people go about their business in the community.

Masks are particularly important in helping to reduce the chances of transmission, and those containing N95 filters are among the most effective. Existing N95 masks can be sterilized through exposure to hydrogen peroxide vapor, and then reused, but the equipment used to perform this sterilization procedure is quite specialized, and is not available in every healthcare facility, particularly in low-resource regions.

This group of researchers has developed an N95 mask that can be easily sterilized using a variety of methods, and safely reused. In doing so, they made sure that the masks could be produced at scale, using injection molding as the means of production. “One of the key things we recognized early on was that in order to help meet the demand, we needed to really restrict ourselves to methods that could scale,” says Giovanni Traverso, a researcher involved in the study. “We also wanted to maximize the reusability of the system, and we wanted systems that could be sterilized in many different ways.”

By using silicone rubber for the main body of the masks, the researchers ensured that they could be sterilized using different techniques, including steam and oven sterilization, and alcohol or bleach soaks. The durable silicone body contains areas where one or two small N95 filters can be popped in, and then removed before sterilization and replaced with a fresh filter thereafter. “With this design, the filters can be popped in and then thrown away after use, and you’re throwing away a lot less material than an N95 mask,” said Adam Wentworth, another researcher involved in the study.

A group of 20 volunteers have tried out the new masks, and they passed a fit test, and the volunteers did not find the masks any less comfortable than a conventional N95 mask. “We know that COVID is really not going away until a vaccine is prevalent,” said James Byrne, a third researcher involved in the study. “I think there’s always going to be a need for masks, whether it be in the healthcare setting or in the general public.”