Japanese researchers at Kobe University and Riken used a Fugaku supercomputer to simulate the benefits of double masking, concluding that wearing two masks provides only marginal benefits compared to wearing one.
The simulation showed that a single surgical, non-woven mask had 85% effectiveness in blocking particles when worn correctly over the nose and mouth. Adding a polyurethane mask increased effectiveness to 89% — a 4% boost.
“The performance of double masking simply does not add up,” according to the researchers. These findings, however, contradict the CDC’s recommendations to double mask by wearing a cloth covering over a surgical mask.
The study advised against wearing two non-woven masks because the air resistance accumulates and causes leakage at the edges. It also concluded that N95 masks are most protective against infection, followed by surgical, cloth, and then polyurethane masks.
