Using surgical wrapping material for the fabrication of respirator masks

Abstract

Given the current shortage of respirator masks and the resulting lack of personal protective equipment for use by clinical staff, we examined bottom-up solutions that would allow hospitals to fabricate respirator masks that: (i) meet requirements in terms of filtering capacities, (ii) are easy to produce rapidly and locally, and (iii) can be constructed using materials commonly available in hospitals worldwide. We found that Halyard H300 material used for wrapping of surgical instruments and routinely available in hospitals, met these criteria. Specifically, three layers of material achieved a filter efficiency of 94%, 99%, and 100% for 0.3 μm, 0.5 μm, and 3.0 μm particles, respectively; importantly, these values are close to the efficiency provided by FFP2 and N95 masks. After re-sterilization up to 5 times, the filter’s efficiency remains sufficiently high for use as an FFP1 respirator mask. Finally, using only one layer of the material satisfies the criteria for use as a ‘surgical mask’. This material can therefore be used to help protect hospital staff and other healthcare professionals who require access to high quality masks but lack commercially available solutions.

A Sew-Free Origami Mask for Improvised Respiratory Protection

“…Importantly, alternative materials such as other fabrics with known filtration efficacy (e.g., see ref. 29–34 ) can be used with the proposed fabrication technique. The origami fabrication procedure represents a flexible solution that can accommodate different facial sizes, and, depending on material choice, realize the full range of filtration properties allowing a user to tune improvised masks to their particular needs.…”

“…The origami fabrication procedure can be used with alternative materials not included here, such as other fabrics with known filtration efficacy (e.g., see ref. 29–34 ).…”

Are surgical masks manufactured from sterilisation wrap safe?

“…Long et al detail a filtration efficiency of 96.5% with two layers of H500 wrap [17]. Meijer et al claim a filtration efficiency of 93.8% through three layers of Halyard H300, whilst Walawalkar et al report an efficiency of 92.1% through two layers [18,19]. However, their methods differ considerably to those outlined in NIOSH regulations with variation in particle size, type, flow rates, and particulate counters.…”

Addressing the global challenge of access to supplies during COVID-19

“…One study looked at repurposing surgical wrapping for creating masks that performed close to the filtration capacity of N95 masks, and with a single layer of the material, worked well to replace surgical masks. 95 Some others looked at using commonly available materials such as polyester, silk, nylon, etc., what their filtration and breathability is, and in one case, whether these materials could be triboelectrically charged to increase filtration. 96 , 97 Another study looked at the effect of combining different fabrics such as silk, chiffon, and cotton to create hybrid masks.…”