THD NewsDesk, CALIFORNIA: Amidst an acute shortage of protective gear, the medical staff were forced to reuse the same N95 masks triggering increased risk of infection. To counter this, a team of Stanford University researchers devised an innovative technique for sterilising facemasks that would allow health workers to reuse the same facemasks. The researchers experimented with a mixture of moderate heat and high relative humidity that was ultimately found beneficial in disinfecting N95 mask materials.
Steven Chu from Stanford University who is also the study’s prime author said,
“You can imagine each doctor or nurse having their own personal collection of up to a dozen masks. The ability to decontaminate several of these masks while doctors are having a coffee break will lessen the chance that masks contaminated with COVID-19 viruses would expose other patients,”.
The researchers, worried about the unavailability of surgical masks, explored a variety of options for disinfection of masks. They employed the use of ultraviolet light, hydrogen peroxide vapours, autoclaves and chemical disinfectants which ultimately degraded the N95 masks’ filtering abilities. Fortunately, sterilisation of N95 masks through a combination of heat and humidity did not distort the masks’ efficiency in filtering out the Covid-19 virus.
The team tested the method by subjecting the mask materials to a liquid form of SARS-CoV-2 virus and subsequently, heated them at moderately high temperatures, with relative humidity up to 100 per cent. Necessary care was taken to ensure that the temperatures were not too high as to deteriorate the mask’s virus-filtering potential.
The team declared their research successful when they could find no trace of coronavirus after exposing the mask fabric to 85°C temperature with 100 per cent relative humidity. Further, the results revealed that the masks disinfected this way could be reused up to 20 times. The discovery is predicted to reduce the requirement of facemasks multifold. Moreover, the study now published in the journal ‘ACS Nano’ also suggests that this technique can be utilised on a minimum of two other viruses, at least.
