AAAR 36th Annual Conference October 16 - October 20, 2017 Raleigh Convention Center Raleigh, North Carolina, USA
Abstract View
Sub-10 nm Particle Emissions from Industrial 3D Printers
ANDREA TIWARI, Jeremy Kolb, Severine Dubroecq, Juergen Spielvogel, Robert Anderson, Brian Osmondson, TSI Incorporated
Abstract Number: 305 Working Group: Indoor Aerosols
Abstract Desktop 3D printers have been previously shown to emit ultrafine particles. While these emissions may pose an inhalation health hazard to the many users of desktop 3D printers, the emissions of industrial printers may pose a workplace health hazard. The focus of this work was to characterize the emissions of a professional 3D printer, with sampling occurring both inside the device’s internal print volume, and in the breathing space of a user standing near the device. One feature available in industrial printers (and more recently in less expensive models) is the use of a water-soluble support material, to permit the printing of more geometrically complex objects. Sampling was conducted during the extrusion of the acrylic copolymer water-soluble support material as well as the acrylonitrile-butadiene styrene (ABS) feedstock. Particle sizes and concentration were measured using an Engine Exhaust Particle Sizer (EEPS), an Optical Particle Sizer (OPS), and a 1 nm SMPS, all from TSI.
Measurements from the interior of the printer show particle concentrations exceeding 1 x 107 #/cm3 during the printing of the acrylic copolymer. The onset of the acrylic copolymer printing was characterized by generation of particles ranging in size from 2.1 nm to over 1 μm. The size distribution at the onset of acrylic copolymer printing had a mode particle size above 60 nm, while the majority of this period was characterized by a particle size distribution peaking around 10-15 nm. To the authors’ knowledge, this is the first study to measure particle production during the printing of a water-soluble support material. ABS printing, in contrast, showed very little particle production; particle counts declined steadily following acrylic copolymer printing until stabilizing at ambient room number concentrations during the ABS print.
Outside of the printer (which was operated with a closed and locked door), acrylic copolymer printing coincided with a sudden elevation of particle number concentration, exceeding 1 x 104 #/cm3, and a mode particle size generally smaller than 40 nm. These results suggest that printing water-soluble support materials may produce measurable particle concentrations within a worker’s breathing space, and may pose a worker health hazard.