Many companies and educational establishments are now incorporating 3D printing into their activities. Whilst 3D printing beings great new possibilities it also brings some specific risks which must be managed.
There are various 3D printing technologies but this post refers to Fused Filament fabrication (FFF) and uses the CLEAPSSS Design and Technology guidance as its basis; CLEAPSS Guidance If you have specific questions or would like to look at exposure for your own printer please contact us using the call back request or the chat link at the bottom right of this page.
FFF technology is the most common form of 3D printing used in SME’s and educational premises, laying down melted plastic filament in a series of layers. The adjacent layers cool and bond together before the next layer is deposited.
In common with most substances which are exposed to high temperatures (over 200oC is not uncommon), the filament printing process can give rise to substances which present a risk to health when inhaled in sufficient quantity or when someone with pre-existing asthma or other breathing issues is exposed. Thought, therefore, needs to be given to how we might prevent these risks through control of exposure and this requires some knowledge of the process itself.
In general, the higher the temperature the greater the generation of fume and the greater the potential for more noxious fume to be generated. In simple terms, you should try to ensure that the printer head is at a temperature which is hot enough for the work to be completed well but not over the temperature (this will vary with print speed and filament thickness). If fume is generated the next risk relates to how exposure occurs, generally you do not need to be close to the print whilst it is in progress and so personal exposure can often be very limited, particularly over an extended print time. A useful control is ventilation, both at the print point and within the room itself. For most situations, a larger room with good ventilation as required under the Work Place Regulations will serve the purpose adequately. For multiple machines operating frequently a more advanced Local Exhaust Ventilation system might be required.
Other safety considerations
In addition to the fume advice above also consider the following points of best practice;
- Some print runs can take many hours, so the ability to pause the print or to split the print job into smaller components may be necessary.
- In a school workshop, the power supplies to equipment should be controlled via a key-controlled electrical shut off. This switch should be lockable, accessible and checked regularly to establish that it is working at all times. This is an essential requirement for workshops, and other rooms, where machines are used; such as graphics rooms; rooms used for systems and control work and preparation rooms where machines are located.
- A 3D printer and any associated LEV may need to be on the same circuit as PCs and other equipment that does not get switched off if the emergency stop button is activated.
- The electrical supply to the machine will need to be fed via a conduit from a fused, labelled switch, which allows the machine to be isolated from the supply when maintenance or servicing is to be carried out. This should not be a standard stand-alone 13A plug which could be accidentally plugged in restoring power to the machine during maintenance.
- Additional stop switches which provide ‘no voltage release ’capacity may need to be provided.
- Third limb switches, such as foot stops, may need to be added.
- Appropriate and effective guards should be provided, which could be interlocked to the machine start system.
- Access to moving parts such as gearbox or belt covers should be secured so that a specialist tool must be used to open the cover(s).
- Subject to a local risk assessment, the machine may require LEV to be installed e.g. an exposure control cabinet.