Mechanical Design Specifications
Figure 1: An exploded view (left) and an assembled view (right) of the components of the iMASC system
Design and generation of injection molded liquid silicone rubber mask
The iMASC system was designed to function as an N95-comparable mask (Fig. 1). The shape of the iMASC system was modeled from disposable regular N95 masks used in the hospital, which are amenable to many different face sizes and shapes. Medical grade liquid silicone rubber (LSR) was identified as an optimal material for mask fabrication due to its conformable capacity, sterilizability through multiple methods and compatibility with injection molding for fabrication scalability. The weight of the iMASC system was 44.84 ± 0.05 grams (n = 3) compared to 10.41 ± 0.13 grams (n = 3) of current N95 masks. We employed a dual filter approach similar to half-mask elastomeric respirators to increase breathability and filtration area. A single regular N95 mask generated up to 5 filters for the iMASC system, thus extending the N95 material use. Furthermore, based upon the material selection of a medical grade LSR, the iMASC system is reusable after sterilization by cleaning with hospital grade bleach/alcohol wipes, autoclave and heating methods.
Figure 2: Front (A) and side (B) images of the completed iMASC system.