Overview of Additive Manufacturing and Potential Occupational Hazards Gary Roth, MS, PhD NIOSH Health Scientist DOE Office of Worker Safety and Health Policy, and IH/OS SIG Webinar 8 January 2019 The findings and conclusions in this presentation have not been formally disseminated by the National Institute for Occupational Safety and Health and should not be construed to represent any agency determination or policy. The National Institute for Occupational Safety and Health The U.S. Federal agency responsible for conducting research and making recommendations for the prevention of work-related injury and illness. Mission: To develop new knowledge in the field of occupational safety and health and to transfer that knowledge into practice. Market Impact of AM Consumer Electronics Aerospace Automotive Medical Comparative Advantages Attribute Traditional Additive Manufacturing Manufacturing Materials Options Vast Small, but growing Quality Control High Varies Throughput High Low Scalability High Low (parallelization) Tool requirements Multiple Single Maximum Complexity Low High Process Modification Difficult Easy Waste material generation High Low Power consumption Low High Labor Pool Existing Training Benefits of AM/3DP •Computer-Aided Design (CAD) Development •Rapid iteration & prototyping •More innovation space •Novel geometries •More complex parts Products •Efficiently use high-cost materials •Customization •Lower material use •Fewer tools Logistics •Just-in-Time fulfillment •Distributed manufacturing PROCESSES The Basics Computer-Aided Design (CAD) Feedstock material Selective x-/y-axis binding Stepwise vertical (z-axis) build Post-Processing Materials & Feedstocks Liquid Resin Solid Plastic Metal Powder … or any permutation thereof. … or something else entirely. Binding/Joining Mechanisms Curing Heat/Cooling Cementing Taxonomy Stereolithography Vat Polymerization Liquid Feedstock Digital Light Processing Material Jetting Material Extrusion Fused-Filament Fabrication Solid Feedstock Sheet Lamination Additive Additive Directed Energy Deposition Selective Laser Melting Manufacturing Powdered Feedstock Powder-Bed Fusion Electron Beam Melting Binder Jetting Selective Heat Sintering Material Extrusion Build Material • Thermoplastic Feedstock Form • Solid filament Selector • Deposition nozzle Binding Mechanism • Melting Powder Bed Fusion Build Material • Metal/Plastic/Ceramic Feedstock Form • Powdered Selector • Laser Binding Mechanism • Sintering / Melting Vat Polymerization Build Material • Photopolymer resin Feedstock Form • Liquid Selector • UV Laser/Projector Binding Mechanism • Curing Binder Jetting Build Material • Metal/Plastic/Ceramic Feedstock Form • Powdered Selector • Printer Head Binding Mechanism • Adhesion/cementing Post-Processing • Wet-chemistry Removing • Powder evacuation material • Manual removal • Annealing Retreating • Curing • Sanding/Polishing Finishing • Texturing • Coating POTENTIAL HAZARDS AM requires a Holistic Approach to Risk Management Materials •Toxicity •Safety •Formulation Process Environment •Energy/Mechanism •Transport/Storage •Consumables •Contamination •Support Processes •Organization Process, Post-Process, and Support Process Hazards Process Support Processes • UV Light, Lasers, Radiation • Ergonomic concerns • Fire/explosion • Falls & falling objects • Cutting injuries • Crushing injuries • Compressed gases • Burns Post-Processing Machine • Ergonomic concerns • Electrical shock • Cutting & grinding injuries • Noise generation • Chemical exposures • Heat generation • Burns • Crushing injuries Materials & Hazards Polymers Acrylonitrile-butadiene-styrene Polylactic acid Particle Emissions Propylene fumarate Poly(vinyl alcohol) Outgassing/VOC Emissions Polystyrene Solvents Dimethyl fumarate Isopropanol Dermal Toxicity Acetone Methyl Ethyl Ketone Reactivity 2-Butanone Metals Aluminum Titanium Flammability Steel Superalloys Combustibility Nanomaterials nFe (steel sintering) nAg (sintering, conductivity) Specific formulation nCB, CNT (conductivity, stiffness, tensile strength) Process-induced changes nSiOx (polymer strength) Environment Transport & Storage Waste Management Workspace Ventilation & Airflow Area Contamination Robotics & Automated Systems Scheduling Psychosocial Stresses Example Hazards Thermoplastic Extrusion Stereolithography • Burns • Chemical dermal contact • Particulate emissions • VOC emissions • VOC emissions • Post-process exposure • Post-process chemical use • Ergonomic hazards Aluminum Laser Sintering Plastic Binder Jetting • Fire/explosion • Fire/explosion • Powder inhalation • Powder inhalation • Powder dermal contact • VOC Emissions • Ergonomic hazards • Post-processing AM users and knowledge will vary Users may differ in terms of … • Budget for OSH activities (controls) Large Enterprises Small-to-Medium Service Locations • Expertise (in both OSH and additive Enterprise manufacturing) • Synergistic exposures • Demographics • Communication preferences • Decision-making structure Hospitals Schools Libraries • Safety culture Safe AM requires Communication Safety Officers • Hazard identification • Risk assessment • Safety controls Designers Operators • Product application • Build operations • Material properties • Support operations • Process principles • Practicalities SUMMARY Additive Manufacturing … Is substantially impacting multiple market sectors Includes many materials and processes Hazards will vary significantly based on particulars Requires rapid and responsible development NIOSH Performs On-Site Research • Over 100 visits (65 sites) • Uses existing methods • Evaluate processes & personal exposures • Provide Guidance and recommendations • Seeking more partnerships and collaborations! References & Image Sources • Bloomington Public Schools (2014) Poplar Bridge Elementary to incorporate 3D printing. URL: https://www.bloomington.k12.mn.us/node/3121478 (accessed 20-Nov-2017). • Florida Public Library (2017) Our 3D Printer. http://www.floridapubliclibrary.org/news/our-3d-printer/ (accessed 20-Nov-2017). • GE Additive (2017a) GE Additive takes bold moves in aerospace industry. https://www.ge.com/additive/press- releases/ge-additive-takes-bold-moves-aerospace-industry (accessed 20-Nov-2017). • GE Additive (2017b) GE Additive to certify new production partners. https://www.ge.com/additive/press- releases/ge-additive-certify-new-production-partners (accessed 20-Nov-2017). • Hewitt, Cooper (2014). Design Dictionary: Powder Bed 3D Printing. Youtube. URL: https://youtu.be/kBHsfNDsbCs (accessed 8-Feb-2017). • McCue, TJ (2018). Wohlers Report 2018: 3D Printer Industry Rises 21 Percent To Over $7 Billion. Forbes. URL: https://www.forbes.com/sites/tjmccue/2018/06/04/wohlers-report-2018-3d-printer-industry-rises-21-percent-to- over-7-billion/#4875d8092d1a (accessed 14-Jun-2018) • O’Conner, Daniel (2013). Formlabs launch new Resin and win CES award. TCT Magazine. URL: https://www.tctmagazine.com/tct-events/formlabs-launch-new-resin-and-win-ces-award/ (accessed 13 Feb 2017). • Open Biomedical Initiative (2016) Japanese medical insurance to cover cost of 3D printed organ models. URL: http://www.openbiomedical.org/japanese-medical-insurance-to-cover-cost-of-3d-printed-organ-models/ (accessed 20-Nov-2017). • Pesce, Mauizio (2015). 3D Printing Materials. Wikimedia Commons. URL: https://commons.wikimedia.org/wiki/File:3D_Printing_Materials_(16837486456).jpg (accessed 13 Feb 2017). • Sęk, Matylda (2011). Crosslinker, UV Stratalinker 2400. Wikimedia Commons. URL: https://commons.wikimedia.org/wiki/File:Crosslinker_UV_Stratalinker_2400-1.jpg (accessed 13 Feb 2017). • Sols Systems (2016) Mapp3D. http://www.sols.com/mapp3d/ (accessed 20-Nov-2017). • Vít, Tomáš (2017). Selective Laser Sintering (or LaserCUSING) cycle. Youtube. URL: https://youtu.be/5-y8iep7jTk (accessed 8-Feb-2017). Acknowledgments • Charles Geraci • Laura Hodson • Kevin L. Dunn • Eric Glassford • Kevin H. Dunn • Duane Hammond • Aleksandr Stefaniak [email protected].