Predicting Concentrations of Ultrafine Particles and Volatile Organic Compounds Resulting from Desktop 3D Printer Operation and the Impact of Potential Control Strategies

Abstract

SummaryRecent studies have shown that potentially hazardous volatile organic compounds (VOCs) and ultrafine particles (UFPs) are emitted from many desktop three-dimensional printer and filament combinations. We use recently published measurements of UFP and speciated VOC emission rates from a number of desktop 3D printers and filaments to predict the magnitudes of human exposures to airborne pollutants that would be expected in multiple locations within a typical small office environment. We also model the impacts of several control strategies for reducing occupational exposures. Results demonstrate that UFP and VOC concentrations within close or moderate proximity (i.e., within 3 and 3 to 18 meters, respectively) to some desktop 3D printer and filament combinations with the highest emissions can exceed recommended exposure levels (RELs) for some VOCs and typical indoor concentrations for both UFPs and VOCs. Concentrations of caprolactam within close proximity to a printer using some nylon-based filaments are predicted to exceed both acute and chronic RELs set by the California Office of Environmental Health Hazard Assessment. UFP concentrations are predicted to reach as high as 80,000 particles per cubic centimeter in close proximity to the highest emitting printer and filament combinations. The printer and filament combinations with the lowest UFP and VOC emission rates are not expected to yield concentrations at levels of concern. The most effective control strategies for reducing both UFP and VOC concentrations included installing a high-flow spot ventilation system and operating the printer in a sealed enclosure with high-efficiency gas and particle filtration.

Research needs and recommendations on environmental implications of additive manufacturing

“…Most of these studies use acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA) filaments and in general ABS leads to higher VOC emission (more than half as styrene). To reduce exposure, enclosing printers and installing high-efficiency particulate air (HEPA) filters at exhaust have been suggested [31], among other strategies [32]. One pilot study has also confirmed the operator's exposure to metal particles during powder handling and laser sintering [33].…”

Charting the Environmental Dimensions of Additive Manufacturing and 3D Printing

“…Mendes and colleagues () characterize emissions from a low‐end 3D printer based on the extrusion of polymers, showing that the process emits nanoparticles inside the chamber, and negligible emissions in room experiments, with emission rates depending strongly on extruder temperature. Following a similar rationale, the article by Azimi and colleagues () predicts the magnitudes of human exposures to airborne pollutants originating from low‐end AM systems that would be expected in multiple locations within a typical small office environment. The results reached demonstrate that emission concentrations within proximity to some systems can exceed recommended exposure levels.…”

“…The investigation of these phenomena, which may all pose potential health risks, will require tailored approaches due to the large number of AM processes, build parameters, and materials. Three articles in this Special Issue address these topics (Graff et al 2017;Mendes et al 2017;Azimi et al 2017).…”

3D Printing and Industrial Ecology

“…Some papers in this special issue advance this line of research (see, e.g., Yang et al 2017;Gutowski et al 2017 Mami et al 2017). It is hoped that the papers on emissions from 3D printing (Bours et al 2017;Azimi et al 2017;Graff et al 2017;Mendes et al 2017) and unit energy consumption will contribute building blocks to future LCA and other systems-oriented work that is typical of IE. The special issue nonetheless provides insights on topics central to IE such as the impact of 3D printing on supply chains (Holmström and Gutowski 2017) and localization of production enabled by 3D production from an environmental perspective (Cerdas et al 2017;Holmström and Gutowski 2017).…”