Health and safety
Research on the health and safety concerns of 3D printing is new and in
development due to the recent proliferation of 3D printing devices. In
2017 the European Agency for Safety and Health at Work has published a
discussion paper on the processes and materials involved in 3D printing,
potential implications of this technology for occupational safety and
health and avenues for controlling potential hazards. Most concerns
involve gas and material exposures, in particular nanomaterials,
material handling, static electricity, moving parts and pressures.
A National Institute for Occupational Safety and Health (NIOSH) study
noted particle emissions from a fused filament peaked a few minutes
after printing started and returned to baseline levels 100 minutes after
printing ended. Emissions from fused filament printers can include a
large number of ultrafine particles and volatile organic compounds
(VOCs).
The toxicity from emissions varies by source material due to differences
in size, chemical properties, and quantity of emitted particles.
Excessive exposure to VOCs can lead to irritation of the eyes, nose, and
throat, headache, loss of coordination, and nausea and some of the
chemical emissions of fused filament printers have also been linked to
asthma. Based on animal studies, carbon nanotubes and carbon nanofibers
sometimes used in fused filament printing can cause pulmonary effects
including inflammation, granulomas, and pulmonary fibrosis when at the
nanoparticle size.
As of March 2018, the US Government has set 3D printer emission
standards for only a limited number of compounds. Furthermore, the few
established standards address factory conditions, not home or other
environments in which the printers are likely to be used.
Carbon nanoparticle emissions and processes using powder metals are
highly combustible and raise the risk of dust explosions. At least one
case of severe injury was noted from an explosion involved in metal
powders used for fused filament printing. Other general health and
safety concerns include the hot surface of UV lamps and print head
blocks, high voltage, ultraviolet radiation from UV lamps, and potential
for mechanical injury from moving parts.
The problems noted in the NIOSH report were reduced by using
manufacturer-supplied covers and full enclosures, using proper
ventilation, keeping workers away from the printer, using respirators,
turning off the printer if it jammed, and using lower emission printers
and filaments. At least one case of severe injury was noted from an
explosion involved in metal powders used for fused filament. Personal
protective equipment has been found to be the least desirable control
method with a recommendation that it only be used to add further
protection in combination with approved emissions protection.
Hazards to health and safety also exist from post-processing activities
done to finish parts after they have been printed. These post-processing
activities can include chemical baths, sanding, polishing, or vapor
exposure to refine surface finish, as well as general subtractive
manufacturing techniques such as drilling, milling, or turning to modify
the printed geometry. Any technique that removes material from the
printed part has the potential to generate particles that can be inhaled
or cause eye injury if proper personal protective equipment is not used,
such as respirators or safety glasses. Caustic baths are often used to
dissolve support material used by some 3D printers that allows them to
print more complex shapes. These baths require personal protective
equipment to prevent injury to exposed skin.
Although no occupational exposure limits specific to 3D printer
emissions exist, certain source materials used in 3D printing, such as
carbon nanofiber and carbon nanotubes, have established occupational
exposure limits at the nanoparticle size.
Since 3-D imaging creates items by fusing materials together, there runs
the risk of layer separation in some devices made using 3-D Imaging. For
example, in January 2013, the US medical device company, DePuy, recalled
their knee and hip replacement systems. The devices were made from
layers of metal, and shavings had come loose Ė potentially harming the
patient.