New device set to recharge masks

A new device, designed by an OIST scientist, can effectively recharge the electrocharged filtration in N95 facepieces, which could help curb the global shortage of facemasks.

The COVID-19 pandemic has heightened the demand for N95 facepiece respirators and face masks, leading to a global shortage. Scientists and engineers around the world have thought creatively about how to counteract this. OIST’s scientists are no exception, with one of them – Professor Mahesh Bandi, who leads the Nonlinear and Non-equilibrium Physics Unit – designing and developing two treatment devices based on commonly available household parts.

N95 facepieces include an electrocharged filtration, which has been shown to be effective at reliably filtering out the virus. Most other facemasks do not possess this electrocharged filtration capability. But even with the N95 facepiece, repeated decontamination and reuse can degrade the embedded charge. Thus, there is a necessity to be able to re-charge N95 facepieces and to also be able to charge the standard surgical and cloth facemasks. 

“The goal of our work was to develop simple designs of a device that could re-charge the N95 facepieces. We also wanted to see if this device would impart charges on standard knitted cloth fabrics,” said Professor Bandi. “It was important that the designs were somewhat accessible, so we used a standard household microwave oven and a commercial Neon sign power supply.”

The resulting device uses a centrifugal fan and an electrode system to create a jet of ions, called corona discharge, which is similar to that produced by the sun. This can effectively clean N95 facepieces and re-charge them. Professor Bandi found that it was also successful, to a degree, at imparting charges on some knitted cloth fabrics, though never to the same level as with the polymeric fabrics that are used for the N95 facepieces.  

Read more about this project on Professor Bandi’s website, at "Electrocharging Face Masks with Corona Discharge Treatment."