Evaluation of the Microbiological Effectiveness of Three Accessible Mask Decontamination Methods and Their Impact on Filtration, Air Permeability and Physicochemical Properties

Abstract

The need to secure public health and mitigate the environmental impact associated with the massified use of respiratory protective devices (RPD) has been raising awareness for the safe reuse of decontaminated masks by individuals and organizations. Among the decontamination treatments proposed, in this work, three methods with the potential to be adopted by households and organizations of different sizes were analysed: contact with nebulized hydrogen peroxide (H2O2); immersion in commercial bleach (NaClO) (sodium hypochlorite, 0.1% p/v); and contact with steam in microwave steam-sanitizing bags (steam bag). Their decontamination effectiveness was assessed using reference microorganisms following international standards (issued by ISO and FDA). Furthermore, the impact on filtration efficiency, air permeability and several physicochemical and structural characteristics of the masks, were evaluated for untreated masks and after 1, 5 and 10 cycles of treatment. Three types of RPD were analysed: surgical, KN95, and cloth masks. Results demonstrated that the H2O2 protocol sterilized KN95 and surgical masks (reduction of >6 log10 CFUs) and disinfected cloth masks (reduction of >3 log10 CFUs). The NaClO protocol sterilized surgical masks, and disinfected KN95 and cloth masks. Steam bags sterilized KN95 and disinfected surgical and cloth masks. No relevant impact was observed on filtration efficiency.

Tailoring the Microstructure of Biodegradable PLA/PBS Melt-Blown Nonwovens with Enhanced Mechanical Performance by In Situ PBS Fibrils Formation

“…Besides, the introduction of the in situ fibrous structure did not destroy the wearing comfort of the nonwovens. The air permeability value and moisture permeability value were 409.42 mm/s and ∼4441 g/(m 2 ·d), respectively, which were similar to the commercial nonwovens reported in recent years. ,,− These findings highlight a new direction in the preparation of biodegradable melt-blown nonwovens with excellent mechanical properties.…”

“…To evaluate the breathability of the MBAS nonwovens, the air permeability values were tested and compared with those of commercial nonwovens reported in recent years. − There was no noticeable difference in the air permeability values of the MBAS nonwovens and the reported commercial nonwovens, as shown in Figure c,d and Table S4. Furthermore, the MBAS nonwovens had a maximum air permeability value of 420.12 mm/s, which was slightly higher than that of the pure PLA nonwoven (407.89 mm/s).…”

Copper-Nanoparticle-Coated Melt-Blown Facemask Filter with Antibacterial and SARS-CoV-2 Antiviral Ability

“…The slight reduction in the air permeability of coated samples (211 ± 15) compared to the uncoated facemask (260 ± 39) can be attributed to the CuNPs filling the melt-blown sample pores, which is noticeable in the SEM images. Notwithstanding, the obtained results are in the same range as those of commercial surgical masks. , On the whole, it can be concluded that the breathability and air flow rate through a facemask with a CuNPs-coated melt-blown fabric as the middle layer are compatible with those of United States National Institute for Occupational Safety and Health approved commercial facemasks.…”

“…Notwithstanding, the obtained results are in the same range as those of commercial surgical masks. 46,47 On the whole, it can be concluded that the breathability and air flow rate through a facemask with a CuNPs-coated melt-blown fabric as the middle layer are compatible with those of United States National Institute for Occupational Safety and Health approved commercial facemasks.…”