Evaluating Measuring Techniques for Occupational Exposure during Additive Manufacturing of Metals : A Pilot Study

Additive manufacturing that creates three-dimensional objects by adding layer uponlayer of material is a new technique that has proven to be an excellent tool for themanufacturing of complex structures for a variety of industrial sectors. Today, knowl-edge regarding particle emissions and potential exposure-related health hazards forthe operators is limited. The current study has focused on particle numbers, masses,sizes, and identities present in the air during additive manufacturing of metals. Mea-surements were performed during manufacturing with metal powder consisting es-sentially of chromium, nickel, and cobalt. Instruments used were Nanotracer (10 to300 nanometers [nm]), Lighthouse (300 nm to 10 micrometers), and traditional filter-basedparticle mass estimation followed by inductively coupled plasma mass spectrometry. Resultsshowed that there is a risk of particle exposure at certain operations and that particle sizestended to be smaller in recycled metal powder compared to new. In summary, nanosizedparticles were present in the additive manufacturing environment and the operators wereexposed specifically while handling the metal powder. For the workers’ safety, improvedpowder handling systems and measurement techniques for nanosized particles will possiblyhave to be developed and then translated into work environment regulations. Until then,relevant protective equipment and regular metal analyses of urine is recommended