Emission of particulate matter from a desktop three-dimensional (3D) printer

Abstract

Desktop three-dimensional (3D) printers are becoming commonplace in business offices, public libraries, university labs and classrooms, and even private homes; however, these settings are generally not designed for exposure control. Prior experience with a variety of office equipment devices such as laser printers that emit ultrafine particles (UFP) suggests the need to characterize 3D printer emissions to enable reliable risk assessment. The aim of this study was to examine factors that influence particulate emissions from 3D printers and characterize their physical properties to inform risk assessment. Emissions were evaluated in a 0.5-m3 chamber and in a small room (32.7 m3) using real-time instrumentation to measure particle number, size distribution, mass, and surface area. Factors evaluated included filament composition and color, as well as the manufacturer-provided printer emissions control technologies while printing an object. Filament type significantly influenced emissions, with acrylonitrile butadiene styrene (ABS) emitting larger particles than polylactic acid (PLA), which may have been the result of agglomeration. Geometric mean particle sizes and total particle (TP) number and mass emissions differed significantly among colors of a given filament type. Use of a cover on the printer reduced TP emissions by a factor of 2. Lung deposition calculations indicated a threefold higher PLA particle deposition in alveoli compared to ABS. Desktop 3D printers emit high levels of UFP, which are released into indoor environments where adequate ventilation may not be present to control emissions. Emissions in nonindustrial settings need to be reduced through the use of a hierarchy of controls, beginning with device design, followed by engineering controls (ventilation) and administrative controls such as choice of filament composition and color.

Evaluation of 3-D printer emissions and personal exposures at a manufacturing workplace.

“…In our chamber testing, we have observed higher particle emissions from ABS relative to PLA [Yi et al, 2016]. In an early study of 3-D printers, Stephens and colleagues reported that printing with ABS increased particle levels in a room relative to when operating with PLA filaments [Stephens et al, 2013].…”

“…In general, the number concentration of particles ranged from 50,000 particles/cm 3 to 200,000 particles/cm 3 of air (see Figure 2) but increased to 450,000 particles/cm 3 of air when printing when using white PLA filament. We have previously evaluated emissions from 3-D printers in a test chamber and observed that some filament colors emit higher levels of particles than others even when made by the same manufacturer [Yi et al, 2016]. The reason why emissions differ by color is not fully understood at this time but may be due to the additives used for coloring the plastics.…”

“…It is known from existing research that 3-D printer-and filament-related factors influence emissions [Yi et al, 2016;Stefaniak et al, 2016]. Changes in printer parameters such as the thickness of each printed layer, the extrusion temperature, build plate temperature, filament feed rate, and number of printers can all influence emissions.…”

“…Once deposited in the lung, it is difficult for the body to efficiently remove these small particles. Breathing in small particles and some organic chemical vapors is associated with irritating the lungs or asthma [Yi et al 2016;Stefaniak et al 2017].…”

Benefits and limitations of three-dimensional printing technology for ecological research

“…Three-dimensional printing is energy intensive and often uses fossil fuel derived virgin plastics which can exist in the environment for ages after disposal and can be toxic to aquatic organisms, especially resin-based printed objects [61]. The printing process itself generates waste due to printers jamming, misprinted models, and scaffolding necessary for more complex 3D objects, as well as harmful emissions in the form of ultra-fine particles and volatile organic compounds [62, 63], which is especially worrisome as most 3D printers are housed in indoor office settings [64]. With respect to the manufacturing of any plastic item, these negative aspects are not completely unique to 3D printing, they just become more obvious when one is directly involved in the manufacturing process.…”