See-through mask filters air with nanoparticle fibres

Two years since the start of the Covid-19 pandemic, masks are a ubiquitous part of life thanks to their vital role in preventing the spread of infection. Their rapid and necessary uptake is not without drawbacks for some members of society however, as their opaque fabric can obscure emotions and cover important visual cues during speech, creating barriers to communication for people with speech and hearing disabilities.

With the huge economic potential of a successful product, a see-through mask that shows expressions while protecting the wearer and people around them could be something of a Holy Grail for the PPE industry. Now, a team of researchers from Kaunas University of Technology (KTU) and start-up Assero in Lithuania claim to have developed just that.

The prototype mask, which is more translucent than transparent, includes a thin fibre of nanoparticles – developed by the team – between two layers of see-through fabric. It recently won international recognition by taking second place in the Silicon Valley Innovation Competition. 

“The masks are made of very small filaments that are 15–20 times smaller than a hair. They have pores through which air can penetrate, but dirt and very small particles are effectively trapped,” said KTU professor Dainius Martuzevičius, who led the work.

Even though the mask is extremely thin, the researchers said the filtration efficiency is not inferior to other respirators. Professional Engineering contacted Professor Martuzevičius for more information on the filtration efficiency and how it compares to other types of mask.

Online sellers promote other types of transparent masks, but they appear to use sheets of plastic more akin to ‘shields’ than filtering fabric. Previous attempts are uncomfortable to wear, fog up, or fail to provide adequate protection, the researchers said.

The start-up Assero was established to commercialise the product, and the team aims to improve filtration efficiency and other important mechanical properties. According to Pranas Šileika, the head of Assero, the product still needs to be tested and improved, with mass production planned for next year.

“We need quality products that allow us to communicate and see other people’s emotions,” Šileika said. “Based on the market's interest in our solution, I think we should reach a production capacity of several million within a couple of years.”

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Content published by Professional Engineering does not necessarily represent the views of the Institution of Mechanical Engineers.