Code Requirements for Industrial Additive Manufacturing and 3D Printing Equipment

Industrial additive manufacturing (AM) has been used for several years, but it continues to gain traction as more companies adopt the technology to produce complex parts with specific material properties for advanced manufacturing applications. By using a layered approach to build components directly from digital models, these systems enable complex designs while helping reduce material waste.

Industrial AM equipment includes large-scale 3D printers along with pre-processing and post-processing systems that support the entire production workflow. These polymer and metal 3D printing systems serve sectors such as manufacturing, aerospace and automotive, offering the ability to create lightweight, high-performance components. However, these technologies also introduce safety risks.

Industrial AM equipment builds parts layer by layer using technologies such as Fused Deposition Modeling (FDM), Selective Laser Sintering (SLS), Stereolithography (SLA) and Powder Bed Fusion (PBF). These polymer and metal 3D printing systems often work with combustible metal powders, high-energy lasers and reactive materials, creating significant risks of fire, electrical shock and hazardous atmospheres. The equipment is now found in a wide range of facilities, including industrial machine shops, contract manufacturers, R&D laboratories, aerospace and automotive manufacturing plants, and medical and dental laboratories — supporting operations such as production of metal parts for aircraft and high-performance machinery, prototype development, tooling, dental components and more. Beyond the printers themselves, the ecosystem includes pre-processing equipment for material handling and preparation and post-processing equipment for curing, heat treatment and finishing — each introducing additional safety risks.

Recent advancements in equipment capabilities and cost reductions have accelerated AM technology adoption globally. Many jurisdictions are now seeing installations in manufacturing facilities across industries, making it important for code authorities to understand the safety risks and code requirements.

Industrial AM systems introduce hazards that differ from traditional equipment. Common risks include:

• Hazardous atmospheres – Combustible dusts, powders and flammable vapors can create ignitable atmospheres within the machine that may lead to flash fires or explosions.  
• Fire hazards – Heat sources, electrical components and process materials can create ignition sources that may result in fire.  
• Electrical shock – High-voltage systems pose shock hazards during use or maintenance.  
• Energy hazards – Lasers, motors and heaters create serious energy-related hazards.  
• Injury hazards – Moving parts and pinch points can cause operator injuries.  
• Laser hazards – Without safeguards, high-intensity beams can damage eyes and skin.  
• Ingestion hazards – Fine metal or polymer powders can contaminate surfaces or become airborne, creating risks of accidental ingestion during handling or maintenance.
• Asphyxiation hazards – Inert gases such as argon or nitrogen used in metal AM systems can displace oxygen in the workspace, creating oxygen‑deficient atmospheres that — without proper ventilation or monitoring — pose serious risks to personnel.

Real‑world incidents underscore these hazards. In 2024, a fire in a San Francisco office building originated in its 3D‑printing laboratory,[1] highlighting that AM areas can present significant fire hazards without proper safeguards. In another case, a dust collector explosion at a metal 3D printing facility in Shanghai[2] occurred when water contacted aluminum alloy powder inside the collector, triggering a hydrogen‑generating reaction that led to a deflagration that killed two workers and injured two others. The U.S. Occupational Safety and Health Administration (OSHA)[3] cited a metal 3D printing shop where reactive metal powders were accumulating in the workspace and ventilation and safeguards were lacking — creating fire and deflagration hazards. 

The International Fire Code (IFC) and NFPA 1 Fire Code include specific provisions for industrial AM equipment. Both model codes require that this equipment be listed and labeled in accordance with UL 2011, the Outline of Investigation for Machinery, or approved for the application based on a field evaluation conducted by an approved agency.

UL 2011 addresses the fire and explosion hazards associated with combustible powders and dusts used in powder bed additive manufacturing systems, incorporating the relevant requirements in NFPA 484 (Combustible Metals), NFPA 652 (Fundamentals of Combustible Dust), NFPA 654 (Combustible Particulate Solids) or NFPA 499 (Hazardous Locations), as applicable. The requirements also consider ignition risks from flammable liquids and vapors used in certain AM processes, with guidance tied to NFPA 497 (Classification of Flammable Vapors and Gases) and NFPA 30 (Flammable and Combustible Liquids Code).

Industrial 3D printers are considered industrial machinery and are therefore subject to the installation requirements in Article 670 of the National Electrical Code® (NEC®). Evaluation to UL 2011 addresses safety considerations and incorporates code requirements for electrical equipment used in industrial settings.

When reviewing plans or conducting inspections, code authorities should verify that industrial AM equipment is either listed in accordance with UL 2011 by an approved certification body (testing laboratory) or has documentation of an approved field evaluation in jurisdictions that have adopted IFC or NFPA 1 as well as the NEC®. This helps code authorities determine whether industrial AM systems comply with applicable fire code requirements and supports operational safety in industrial settings.

Additional hazards may arise across the material-handling chain, including powder storage, transfer mechanisms, printing operations, thermal processes and post‑processing steps such as depowdering or finishing. When flammable gases, vapors, combustible dusts, fibers or flyings may be present in the area surrounding the machinery, the installation is also subject to the applicable provisions of NEC® Articles 500, 501, 502 and 503, depending on the nature of the hazardous material encountered.

UL Solutions certifies (lists) AM equipment under the product category Machinery (GPNY) for compliance with UL 2011, the Outline of Investigation for Machinery. Guide information and certifications (listings) can be viewed on Product iQ®.  Product iQ is available at no cost but requires a one-time registration. Once registered, enter GPNY in the search field.

To learn more about UL Solutions’ services for AM and 3D printing equipment, visit our Additive Manufacturing service page.