It’s been mentioned by professional 3D printer vendors and users for a couple of years now—many desktop 3D printers should be installed in well-ventilated areas, just like the larger professional machines. Now, there is research to back up this suggestion.

In a recent paper, Emissions of ultrafine particles and volatile organic compounds from commercially available desktop three-dimensional printers with multiple filaments, published by the American Chemical Society, authors Parham Azimi, Dan Zhao, Claire Pouzet, Neil E. Crain, and Brent Stephens, released their findings.

They tested the following 3D printers:
MakerBot,
XYZ,
FlashForge,
Dremel,
LulzBot,

using the following materials:
ABS,
PLA,
transparent Polycarbonate,
TGlase (a transparent polyester resin filament),
high-impact polystyrene (HIPS),
PCTPE (a semitransparent nylon-based plasticized copolyamide thermoplastic elastomer),
semitransparent Nylon,
Laywood (an imitation wood material of unknown chemical composition),
and Laybrick (an imitation brick material of unknown chemical composition).

These lists of printers and materials were not meant to be exhaustive, noted the authors. They represent a range of currently popular printers, filament type, nozzle and bed temperatures, and the presence or absence of a partial enclosure.

Previous research, noted the authors, indicated that desktop 3D printers can emit large numbers of ultrafine particles (UFPs) of less than 100 nm and some hazardous volatile organic compounds (VOCs) during printing.

Exposure to emissions from thermal decomposition of thermoplastics has been shown to have toxic effects in animals and exposure to UFPs from other sources has been linked to a variety of adverse human health effects.

The results of this research show that more testing is needed but that these desktop printers do give off emissions of ultrafine particles and volatile organic compounds, in some cases in sufficient quantity to cause health issues. The research also indicates that proper installation in a well-ventilated area reduces the risks of these particles and compounds and the printers can be used under such conditions.

Key points about the research:

–A 10 × 10 × 1 cm standard sample from the National Institute of Standards and Technology (NIST) was used for all but one of the tests. Particle concentrations were continuously measured inside the exhaust port of the chamber with a TSI model 3007 condensation particle counter (CPC) logging at 1 min intervals.

–Chamber air was also sampled during the tests for VOC analysis using Tenax-GR sorbent tubes.

–The Dremel, XYZprinting, and MakerBot printers are enclosed although not airtight. The FlashForge and LulzBot printers do not have enclosures. Those with enclosures emitted slightly fewer ultrafine particles and volatile organic compounds.

–High amounts of ultrafine particles occur during the first 20 minutes or so of printing. Then they taper off. “However,” noted the report, “the magnitude and shape of dynamic UFP concentrations varied widely depending on the printer, filament, shape of printed object, and nozzle and bed temperatures.”

–The highest UFP emission rates occurred with the printers using ABS filaments, across all ABS printers with or without enclosures.

–The lowest UFP emission rates occurred with PLA filaments, regardless of printer make and model.

–Median UFP emission rates were highest for polycarbonate filament, followed by PCTPE, T-Glase, HIPS, nylon, laywood, and laybrick.

–The concentration of styrene was found to be about 20 times higher than that typical of what is found in commercial buildings. There are reports that suggest exposure to styrene at these levels could affect human health.

Interestingly, filament material had the most variations in volatile organic compounds. But these variations were strongly influenced by the printer make and model.

Symptoms users may experience with these emissions include irritated eyes and some respiratory problems. Some of these emissions may also affect the central nervous system.

How do we reduce user exposure to these emissions? The authors make the following suggestions:

–Manufacturers should work to develop low-emitting filament materials or low emitting 3D printers.

–Manufacturers might want to evaluate the effectiveness of sealed enclosures on these emissions or include filtration systems in their printers.

–Other suggestions include installing desktop printers in a well-ventilated area.

To read the full report, click here.

Leslie Langnau
llangnau@wtwhmedia.com