New replaceable, more efficient filter for N95 masks developed

Researchers from King Abdullah University of Science and Technology (KAUST) in Saudi Arabia have developed a more efficient membrane filter that can be attached to a regular N95 mask and replaced when needed. The filter has a smaller pore size than normal N95 masks, potentially blocking more virus particles. The new study has been published  in ACS Nano.

Since the outbreak of COVID-19, there's been a worldwide shortage of face masks -- particularly, the N95 ones worn by health care workers. Although these coverings provide the highest level of protection currently available, they have limitations.

Now, researchers have developed a membrane that can be attached to a regular N95 mask and replaced when needed. The filter has a smaller pore size than normal N95 masks, potentially blocking more virus particles.

N95 masks filter about 85% of particles smaller than 300 nm. SARS-CoV-2 (the coronavirus that causes COVID-19) is in the size range of 65-125 nm, so some virus particles could slip through these coverings. Also, because of shortages, many health care workers have had to wear the same N95 mask repeatedly, even though they are intended for a single use. To help overcome these problems, Muhammad Mustafa Hussain and colleagues wanted to develop a membrane that more efficiently filters particles the size of SARS-CoV-2 and could be replaced on an N95 mask after every use.