During the Corona crisis, protective masks have become a rare commodity. In order to equip Switzerland with sufficient protective equipment during future pandemics, Empa researchers are working together with a national consortium of researchers, health care experts and partners from industry on the "ReMask" project: New types of masks and technologies for reusing existing protective equipment are being developed - for now, but also for future pandemics. Moreover, information on the manufacture of masks and textile protective systems as well as on standardized test methods have already been made publicly available.
In the Corona crisis, Swiss researchers are joining forces. In order to meet Switzerland’s need for protective equipment, researchers from Empa, ETH Zurich, EPFL and the Spiez Laboratory, together with a large number of partners from the health care sector and industry, have launched the "ReMask" project ( https://www.empa.ch/web/remask ). The aim is to develop technologies to reuse existing masks, domestic production of efficient protective equipment and alternative masks with new properties to trap and kill viruses.
The knowledge gained from ReMask is to support the recently established "National COVID-19 Science Task Force", whose experts advise the Federal Office of Public Health (FOPH) and other federal agencies on tackling the pandemic. One of the Task Force’s high-priority tasks is the endeavor led by Peter Wick (Empa), Sarah Tschudin Sutter (Uni Basel) and Andreas Mortensen (EPFL) to develop projects for the production and reuse of protective masks. With ReMask this multidisciplinary approach is now being implemented. The expert group "Masks" of the Science Task Force has now issued a recommendation for minimum quality requirements for so-called "community masks" for the population. Based on these recommendations , Empa will temporarily investigate such community masks during the current crisis situation, until the relevant know-how can be transferred to an independent institution.
Surgical masks (right) are designed to prevent larger droplets of pathogens from being ejected by the wearer. They therefore protect the user somewhat less, as small particles can pass to the inside, and the mask does not sit tightly on the face. On the other hand, they protect the surroundings from virus-containing droplets from an infected wearer.
Respiratory protection masks of the type FFP-2 ("filtering face piece") are different: FFP-2 masks (left) are designed to protect the wearer from pollutants and pathogens in the environment. The smallest particles that can be trapped are around 600 nanometers in size. Both types of masks are currently only intended to be worn once.
Thirdly, there are the so-called community masks or hygiene masks, which are not covered by the certified standards of the other two types of masks. The use of community masks is - as the name suggests - intended for the general population as a way to minimize the risk of transmission and thus protect the environment. (Images: Unsplash/istock)
In the Empa laboratories, research projects are already underway to overcome bottlenecks in the short term, with the aim of enabling the reuse of masks. This also ensures a more sustainable use of material resources in the long term. Among other things, it must be established how the masks can be sterilized without damaging them, how they can be stored for long periods, and how their effectiveness can be verified beyond doubt even after repeated use.
To avoid the use of dangerous viruses for these experiments, the researchers are working with non-infectious particles that simulate the events on the inside and outside of a mask similar to a droplet infection. "We are currently developing devices that can reproduce these conditions," says Empa researcher René Rossi from the Laboratory for Biomimetic Membranes and Textiles in St. Gallen. Other mask properties such as air permeability (<60 Pa/cm2), splash water resistance (impermeable to splash water) or the efficiency of filtration against small particles (filtration efficiency of 70% for particles with a size of 1 micrometer) must also be investigated. The test protocols that will be developed for this purpose are distributed to companies that manufacture masks, filters and protective equipment. "It’s all about a timely, nationwide effort," says Rossi. That’s why the researchers don’t work with a designated industrial partner, but have brought the entire industry on board.
For the ReMask project, experts from research, health care and industry have joined forces to provide urgently needed products, concepts and services in a timely manner to provide technologies for the control of COVID-19. At Empa the Laboratory for Biomimetic Membranes and Textiles, the Particles-Biology Interactions Lab, the Transport at Nanoscale Interfaces Lab, the Center for X-ray Analytics and the Biointerfaces Lab are involved.
Partners: ETH Zurich, EPFL, Spiez Laboratory, University Hospital Zurich, Inselspital Bern, "Centre hospitalier universitaire vaudois" (CHUV), "Hôpitaux Universitaires de Genève" (HUG), Wintertur Cantonal Hospital, Spital Wallis, Regio 144 AG, Indema AG and 200 companies of the Swiss Textiles industry association ( https://subitex.empa.ch ).
ReMask’s medium and long-term goals also include the development and production of novel masks and mask components. For instance, additional layers on the inside and outside of conventional masks will improve their durability and functionality. On the masks’ inside, a water-binding layer is intended to bind moisture from the breath of the wearer. On the outside, the Corona virus is to be specifically blocked. It is already known that the Corona-like pathogen envelope is negatively charged. "Coatings on fibers or membranes that are positively charged would electrostatically bind and thus block the virus on the outside of the mask," explains Rossi.
The researchers also want to develop textiles with virucidal properties. Rossi: "We are pursuing several approaches, with which Corona viruses that land on the textile can be inactivated. This work will build on the knowledge gained in the course of a previous project. Within this project of Empa and EPFL , a face mask was developed, which is equipped with a novel filter foil. These new, more robust and powerful masks must also withstand the test procedures that are already being implemented for used masks.
For the production and functionalization of protective masks, Swiss companies will be involved. Thus, ReMask is not only a research project but also a business development project, which will provide orders to Swiss companies during the Corona crisis.
In recent years, more than half of all Swiss "deep tech" start-ups have emerged from institutions of the ETH Domain, creating new technologies, services and jobs. To ensure that the innovative and economic performance of start-up companies in Switzerland is not jeopardized by the corona crisis, the ETH Domain recently launched a new initiative, in which Empa is also involved. The "COVID-19 Start-up Task Force" is to support highly qualified young companies in the current crisis situation. It also facilitates synergies and contacts with economic experts of the "National COVID-19 Science Task Force" and the most important stakeholders in the Swiss start-up ecosystem.