Floyd Evan L, Wang Jun, Regens James L
a Department of Occupational and Environmental Health, College of Public Health , University of Oklahoma Health Sciences Center , Oklahoma City , Oklahoma.
J Occup Environ Hyg. 2017 Jul;14(7):523-533. doi: 10.1080/15459624.2017.1302587.
3-D printing is an additive manufacturing process involving the injection of melted thermoplastic polymers, which are then laid down in layers to achieve a pre-designed shape. The heated deposition process raises concerns of potential aerosol and volatile organic compounds (VOC) emission and exposure. The decreasing cost of desktop 3-D printers has made the use of 3-D printers more acceptable in non-industrial workplaces lacking sufficient ventilation. Meanwhile, little is known about the characteristics of 3-D printing fume emission. The objective of this study was to characterize aerosols and VOC emissions generated from various filaments used with a low-cost 3-D printer in an environmental testing chamber. A pre-designed object was printed in 1.25 hours using eight types of filaments. A scanning mobility particle sizer and an aerodynamic particle sizer were employed to measure the particle size distribution in sub-half-micron fraction (<0.5 µm) and super-half-micron fraction (0.5-20 µm), respectively. VOC concentration was monitored real-time by a photoionization detector and sampled with a tri-sorbent thermal desorption tube, and analyzed by thermal desorption gas chromatography mass spectrometry (TD-GC/MS). Results showed high levels of fume particles emission rate (1.0 × 10 to 1.2 × 10 #/min) in the sub-half-micron range with mode sizes of 41-83 nm. Particle concentrations peaked during the heat-up and solid layer printing periods. Total VOC concentration in the chamber followed a first-order buildup, with predominant VOC species in the chamber were breakdown and reaction products of the filaments, such as styrene from ABS filaments. These findings and exposure scenario estimation suggest that although the VOC concentrations were much lower than occupational exposure limits, particles with size less than micron might be a concern for users of low-cost 3-D printers due to high respirablity, especially if used in settings without proper guidance and engineering control.
3D打印是一种增材制造工艺，涉及注入熔化的热塑性聚合物，然后将这些聚合物逐层铺设以形成预先设计的形状。加热沉积过程引发了对潜在气溶胶和挥发性有机化合物（VOC）排放及暴露的担忧。桌面3D打印机成本的降低使得在通风不足的非工业工作场所使用3D打印机变得更可接受。与此同时，人们对3D打印烟雾排放的特征知之甚少。本研究的目的是在环境测试舱中对使用低成本3D打印机的各种细丝产生的气溶胶和VOC排放进行特征分析。使用八种类型的细丝在1.25小时内打印出一个预先设计的物体。分别采用扫描迁移率粒径分析仪和空气动力学粒径分析仪测量亚半微米级（<0.5 µm）和超半微米级（0.5 - 20 µm）的粒径分布。通过光离子化探测器实时监测VOC浓度，并用三吸附剂热解吸管进行采样，然后通过热解吸气相色谱质谱联用仪（TD - GC/MS）进行分析。结果表明，在亚半微米范围内，烟雾颗粒排放率较高（1.0×10至1.2×10#/分钟），模态粒径为41 - 83纳米。颗粒浓度在加热和实体层打印期间达到峰值。测试舱内的总VOC浓度遵循一级累积规律，舱内主要的VOC种类是细丝的分解和反应产物，如来自ABS细丝的苯乙烯。这些发现和暴露场景估计表明，尽管VOC浓度远低于职业暴露限值，但由于小于微米级的颗粒具有高可吸入性，对于低成本3D打印机的使用者来说可能是一个问题，尤其是在没有适当指导和工程控制的环境中使用时。
