2016 ASHRAE Annual Conference

3D printers are used in various applications, by designers and students for their inventions, as well as industrial, medical, and residential purposes. Fused deposition modeling (FDM) is the most common type of desktop 3D printers, where a coil of thermoplastic filament is heated as it extrudes from a nozzle to a moving platform, building the object layer by layer. 3D printers may emit toxic gases and particulates that deteriorate indoor air quality, especially since they are typically operated indoors for hours at a time. Currently, little is known about desktop 3D printer emissions. We have developed a methodology for characterizing and quantifying emissions from an operating 3D printer. The protocol measures for fine particulate and volatile organic compound (VOC) concentrations over time to determine emission factors and human exposure potentials.  Chemical composition and toxicity of raw filaments as well as emitted particulates were also examined. Early findings indicate that 3D printers can be a significant source of indoor air pollution. A review of particulate and VOC emissions from 3D printers using various filaments will be presented. Key factors that influence the emissions and healthier alternatives for consumers will be identified. Implications of this study towards establishing compliance standards for 3D printers and its filaments will be presented.

Humans typically spend 90% of their time indoors. Indoor air pollution in working places is widely recognized as one of the most serious potential environment risks to human health. Three-dimensional (3D) printers are a growing field with the global 3D printing market projected to grow from $2.5B in 2013 to $16.2B by 2018. Previous studies measured that certain 3D-printers emits large numbers of nanoscale particles. Current MHVAC (Mechanical Heating, Ventilation and Air-conditioning) system designs have filtration devices with low to zero effective efficiency against nanoscale particles. Furthermore, there is no consideration of a local ventilation system for the spaces occupied by 3D printers. This situation conceptually leads to a high concentration of nanoscale particles and particle cross-pollution amongst different ventilated spaces. High concentrations of nanoscale particles can cause severe health problem for those occupants with long-term exposure to indoor nanoscale particles because of particle deposition deep into the lungs and potentially crossing the barrier into the blood circulation. It is well established that nanoscale particles can trigger inflammation and cause serious cardiovascular and respiratory problems when inhaled.  Although there have been limited studies on indoor nanoscale particles emitted from 3D printers, no studies have been reported on their dispersion and deposition in ventilated spaces. This paper presents the preliminary measurement of indoor nanoscale particle concentration levels and surface temperatures from different types of 3D-printers in a ventilated space.  The experimental set-up and measurement protocol will be described, followed by some preliminary data analysis. It is expected such data will be used for providing boundary conditions in the latter CFD simulation.  The ultimate objective of this research is to understand the impact of MHVAC strategies and designs on indoor air quality in ventilated spaces with 3D printers.