Moldable Mask: A Reusable, Hot Water Moldable, Additively Manufactured Mask to Be Used as an N95 Alternative

Abstract

There has been high demand for personal protective equipment (PPE) during the COVID-19 pandemic, especially N95 respirators. Unfortunately, at the early stage of the pandemic, the supply could not meet the demand for N95 respirators, leading to a shortage and unsafe reuse of this form of PPE. We developed the Moldable Mask to ease the demand for N95 respirators by creating a 3D-printed mask that uses a piece of N95 material as a filter. A sheet of N95 material could be used or one N95 respirator to be turned into two masks. The main feature of the mask is the ability to easily mold it in hot water to create a custom fit for each user. It can also be easily assembled at home with affordable materials. The final mask design was qualitatively fit tested on 13 subjects, with all subjects showing an improvement in fit with the hot water molding technique and 10 (77%) subjects passing the fit test. This shows that the Moldable Mask is a viable option for a safe, affordable N95 alternative when N95 mask supply is strained.

A systematic review of passing fit testing of the masks and respirators used during the COVID-19 pandemic: Part 1-quantitative fit test procedures

“…Thirteen studies reported that there were significant differences in passing fit test rates of masks or respirators [ 39 – 41 , 65 , 69 , 77 , 94 , 108 , 111 , 127 – 131 ]. In the study by Martelly et al, the significant level was not reported; however, due to the considerable difference between the two studied respirators, it could be considered as a statistically significant difference in terms of FF (7.0 vs. 143) [ 129 ]. Whereas, no significant differences were determined between the studied masks or respirators in the six studies [ 32 , 48 , 51 , 63 , 131 , 132 ].…”

“…Keeping the top strap from sliding to the back of the head caused problems for the subjects with short and smooth hair, which in turn influenced the fitting during fit testing. Other subjects with long or short, textured hair keep the strap from sliding by either using a ponytail or friction [ 129 ]. It is evident that the subjects’ hairstyle acted as an interference factor, causing the head straps to slip and loosen, thereby disrupting the proper fit.…”