(in German)

Additive manufacturing - also called 3D printing - is increasingly used for the production of prototypes (rapid prototyping), tools (rapid tooling) and the series production of industrial components (rapid manufacturing). Powders consisting either of metallic alloys or of synthetic polymers of varying composition are used for these powder-bed processes.

In the framework of the investigation program, workers' inhalation exposure to released airborne particles of the applied powders and reaction products has been determined by means of workplace measurements. Both personal air sampling and stationary sampling in accordance with the Technical Rule for Hazardous Substances (TRGS) 402 took place in ten enterprises. The workplace measurements focused on processes in automotive, aeronautical engineering and tool manufacturing industry. Additionally, producers of 3D devices were included in the investigation. In powder-bed processes workers are exposed to the respirable and inhalable particle fraction and hazardous substances contained in these particle fractions. Furthermore, gases and volatile organic compounds (VOC), e.g. as decomposition products, contribute to the exposure.

The occupational exposure limits (OEL) were adhered to both for inhalable and respirable particles in nine out of ten enterprises. Exceedings of the OEL for the respirable particle fraction have been found in one enterprise processing polymer powders. For all other substances - including the decomposition products - the OELs were adhered to when polymer powders were processed. On the other hand, when processing metallic alloy powders exceedings of the OELs have been measured for some metal species.

Based on measured workers' exposure general recommendations for good practice have been derived to support the enterprises ensuring safe work with hazardous substances in additive manufacturing.

Please download the complete report "Determination of hazardous substances exposure during 'Additive Manufacturing' - Application of powder-based systems" (in German only).