Design of customizable personal protective equipment for 3-D printing: Performance evaluation of N95 respirators using computational fluid dynamics

Abstract

3-D printing the structural components of facemasks and personal protective equipment (PPE) based on 3-D facial scans creates a high degree of customizability. As a result, the facemask fits more comfortably with its user’s specific facial characteristics, filters contaminants more effectively with its increased sealing effect, and minimizes waste with its cleanable and reusable plastic structure compared to other baseline models. In this work, 3-D renditions of the user’s face taken with smartphone laser scanning techniques were used to generate customized computer-aided design (CAD) models for the several components of an N95 respirator, which are each designed with considerations for assembly and 3-D printing constraints. Thorough analyses with computational fluid dynamics (CFD) simulations were carried out to verify the respirator’s efficiency in filtering airborne contaminants to comply with industry safety guidelines and generate data to showcase the relationships between various input and output design parameters. This involved a comparative study to identify the ideal cross-sectional geometry of exposed filter fabric, a sensitivity study to evaluate the respirator’s ability to protect the user in various scenarios, and the 3-D printing of several prototypes to estimate printing time, cost of materials, and comfort level at the user’s face. Results showed that the combination of different digital tools can increase efficiency in the design, performance assessment, and production of customized N95-rated respirators.

Keywords:

• Additive manufacturing
• computer-aided design
• facemask design
• numerical simulation
• three-dimensional face scan

Acknowledgments

The authors would like to thank Anna Bruno (Mr. and Mrs. Milton K. Morgan III Makerspace at the Charles H. Diller Jr. Center for Entrepreneurial Leadership and Innovation) and Scott Donald (Shippensburg University Media Services) for the collaboration on the 3-D printing of the prototypes used in the analysis, and Reiner Heydemann for allowing to use his face as the template for respirator design. The authors report there are no competing interests to declare.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This research project was funded by the Faculty Professional Development Council Annual Grant Program of Shippensburg University of Pennsylvania.