To overcome the challenge of shortage of supplies of N95 masks, a hospital in United States collaborated with the Washington University School of Medicine to implement a method to disinfect and reuse N95 masks up to 20 times each. The method utilizes vaporized hydrogen peroxide (VHP) as a disinfectant and ensures that the healthcare workers receive their own masks back after disinfection. The approach can help reduce the demand for protective masks and allow hospitals to operate on limited supplies.
The process begins with the healthcare worker, at the end of their shift, removing the mask and placing it into a sterilization pouch, writing their name, id, and other identifying information on the pouch and placing it in a soiled collection bin. A designated worker, wearing proper protection, gathers the collection bins twice a day and takes them to a specially designed, sealed disinfection (VHP) room.
The pouches are arranged, and a hydrogen peroxide vapor generator (Bioquell Z-2- is a complete solution for zone bio-decontamination offering user friendly operation. It fills the room with decontaminating hydrogen peroxide vapor. The disinfection takes 4.5 hours, after which a worker moves the racks of masks to another area to off gas hydrogen peroxide with the help of fans. The masks stay in this room until sensors no longer detect hydrogen peroxide in the air. The pouches are then returned to their respective hospital units. The whole process takes about 7 hours total and can be repeated about twenty times. The researchers found that after 20 disinfection cycles the masks no longer fit well.
This program is a welcome improvement for extended usage of N95s during the shortage that medical facilities are facing today.