Background: The main function of respiratory protective devices is to provide an intact physical barrier between the environment and the user. To ensure that, a leak-tight fit of the facepiece to the user's face is essential, regardless of the user's individual facial features.
Objective: The main objective of this study was to assess the possibilities of developing customized respirators well-fitting to the anthropometric dimensions of the user's face using 3D scanning and 3D printing techniques and to evaluate this custom-made device in terms of protective, usage and strength parameters.
Methods: Commercially available twin-filter half-mask type MP22/2 was selected as base model for customization. The 3D scans of the half-mask facepiece were performed using ATOS Core optical 3D scanner. Simultaneously anthropometric measurements of the test subject face were carried out with hand-held 3D scanner Artec EVA. Then digital model of the facepiece was matched to the shape of user's face using Geomagic Touch X haptic device. Customized facepieces were printed out with use of selective laser sintering technique from thermoplastic polyurethane. After assembling, respirators were tested for compliance with the requirements of the European standards.
Results: The developed respirators proved to be very well-fitted to the user's face, did not cause any imprints or skin irritations and were assessed positively in terms of protective, usage and strength parameters.
Conclusions: The application of 3D scanning and 3D printing techniques for designing and fabricating customized half-mask facepieces constitutes a viable option for the future development of respiratory protective devices.
Keywords: Respiratory protective devices; additive manufacturing; fit of respirators; total inward leakage.