You are here

3D Printed Manufacturing of Respiratory Protection

Description:

TECHNOLOGY AREA(S): Chem Bio_defense, Materials 

OBJECTIVE: Develop additive manufacturing processes to produce a fully functional Air Purifying Respirator (APR). Demonstrate advantages of 3D printed manufacturing to provide innovations such as custom sizing and use of multifunctional elastomeric composites. 

DESCRIPTION: Many respiratory protection systems are designed for a high threat environment. These threat levels and quality assurance requirements posed upon respiratory protection devices currently drive the utilization of expensive and timely production processes such as rubber and plastic injection molding. Limitations of injection molding include cost, time, and an inability to produce multifunctional composite materials. Also, small run respirator modifications or customizations are typically cost prohibitive. Additive manufacturing allows for improvement in manufacturing cost and time but does not currently account for the production of materials that offer the strength or permeation resistance required for respiratory protection systems. Also, layered 3D printing techniques do not result in smooth surfacing and some resin based options do not have the print bed or working time requisite for a full facepiece respirator. This effort seeks to overcome these challenges by pursuing a technological manufacturing innovation that is critical to a strong manufacturing sector in the U.S. economy. The focus of this effort is to develop a respiratory protective device utilizing innovative additive manufacturing technologies and processes. Innovative technologies and multifunctional elastomeric composite materials are needed to allow custom sized manufactured respirators to be produced at a cost effective price and in a timely manner. Additive manufacturing processes of composite elastomeric materials offer many potential advantages. Potential advantages could include a respirator facepiece consisting of a soft internal comfort layer near the face and a rugged threat agent resistant layer on the exterior. Even further, a composite layer providing ballistic, fire, or other operationally tailored levels protection could be achieved. Materials developed shall have threat agent permeation resistance characteristics required by the NIOSH Statement of Standard for Chemical, Biological, Radiological, and Nuclear (CBRN) Full Facepiece Air Purifying Respirator (APR). Durability and tensile requirements shall compare favorably to existing military respirator materials and shall comply with requirements set forth in MIL-STD 810G. 

PHASE I: Investigate innovative elastomeric and/or composite materials and additive manufacturing processes that would result in eight vertically printed coupons (4” diameter; .05” thickness) that are resistant to chemical warfare agent materials as required by the NIOSH Statement of Standard for CBRN Full Facepiece Air Purifying Respirator APR. Provide eight coupons to the Government for testing. Perform and demonstrate in house durability and tensile strength testing of additional coupons of simple and complex geometries. Referencing Government-owned and provided M40 APR technical data, develop designs that illustrate in detail how these elastomeric and/or composite materials would be used to develop a full facepiece system. Show how the necessary production quality attributes can be met, especially those related to a good respirator to face seal. Assess materials chosen for human safety. 

PHASE II: Refine the material and production technology chosen to develop a full elastomeric facepiece of size equivalent to the M40 APR. Technology demonstrated will be capable of printing a minimum of 10” (L) x 8” (W) x 8” (H) print volume and will exhibit smooth sealing surfaces. Exact APR face seal size and shape produced will be based on head and facial anthropometric characteristics of five test subjects. A full facepiece APR will be constructed using these custom facepieces and government provided M40 component hardware, to include the filter. The ability to co-print multiple materials to reduce hand assembly will be demonstrated. A preliminary laboratory respiratory protection level (LRPL) test of these five constructed APRs on the chosen test subjects will be performed at this stage. The LRPL of the APR shall be 2000 or greater, for 95% of trials, sampled in the breathing and ocular zone of the respirator. The APRs developed should comply with the NIOSH Statement of Standard for CBRN Full Facepiece Air Purifying Respirator APR. PHASE III: Improve the APR design by demonstrating the incorporation of customized hardware, allowance for improved human factors, and operational tailoring. Demonstrate the scalability of the technology to print a NIOSH compliant APR in under 12 hours. 

PHASE III: PHASE III: Improve the APR design by demonstrating the incorporation of customized hardware, allowance for improved human factors, and operational tailoring. Demonstrate the scalability of the technology to print a NIOSH compliant APR in under 12 hours. PHASE III DUAL USE APPLICATIONS: Potential alternative applications include industrial, pharmaceutical, healthcare, international, and other commercial respiratory protection uses as well as protection systems beyond the respirator. 

REFERENCES: 

1: Anonymous. (2017, June 29). "3D printers start to build factories of the future." The Economist, retrieved from http://www.economist.com

2:  Anonymous (2017, June 29). "3D printers will change manufacturing." The Economist, retrieved from http://www.economist.com

3:  Exec. Order No. 13329 (2004). Encouraging Innovation in Manufacturing.

4:  Melnikova, R., Ehrmann A., and Finsterbusch, K., (2014). 3D printing of textile-based structures by Fused Deposition Modelling (FDM) with different polymer materials. Paper presented at 2014 Global Conference on Polymer and Composite Materials.

5:  Military Standard, MIL-STD-810G, Environmental Engineering Considerations and Laboratory Tests, Revision G (DOD 31 Oct 2008).

6:  National Institute for Occupational Safety and Health (2004). Statement of Standard for Chemical, Biological, Radiological, and Nuclear (CBRN) Full Facepiece Air Purifying Respirator (APR). Retrieved from https://www.cdc.gov/niosh/npptl/standardsdev/cbrn/apr/standard/aprstd-a.html

7:  Rudykh, S., Ortiz, C. and Boyce, M. (2015). Flexibility and protection by design: imbricated hybrid microstructures of bio-inspired armor. Soft Matter, 11, 2547-2554.

8:  Yakout, M. and Elbestawi, M. (2017) Additive Manufacturing of Composite Materials: An Overview. Paper presented at the International Conference on Virtual Machining Process Technology.

KEYWORDS: Individual Protection, Respiratory Protective Mask, 3D Printing, Additive Manufacturing 

CONTACT(S): 

Daniel Barker 

(410) 436-4770 

daniel.j.barker.civ@mail.mil 

US Flag An Official Website of the United States Government