A VOC sensor system installed on a 3D printer [Source: Hackaday]
I’m reading an intriguing post on Hackaday, where a contributor has provided a design for a 3D printer emissions sensor.
3D printers do indeed emit some nasty materials. When materials are heated they tend to emit nanoparticles that, due to their low weight, become airborne in the printer’s vicinity. Worse, however, are the emissions of volatile organic compounds, or “VOCs”. These are chemicals that could be toxic, carcinogenic or harmless. The problem is that once emitted, these could be inhaled and cause health troubles later on.
3D Print Emissions
Sometimes this is noticeable as certain materials present odors when used. Resins in particular can evaporate and place a myriad of substances in the nearby air. But just because you cannot smell anything doesn’t mean there are no VOCs.
The standard advice is that any 3D printer setup should include a method of ventilation, where the VOCs and nanoparticles are simply blown outside. In cases where there are no possibilities for venting, a standalone filter unit should be used. These units include powerful filtration elements that catch virtually all of the nanoparticles and VOCs.
Homebuilt 3D Print VOC Sensor
Now I see how Hackaday contributor Gary Peng has provided an easy-to-build design for a VOC sensor. The idea is to place the sensor near or on an operating 3D printer, where it will quietly monitor VOCs and alert the operator when VOCs exceed tolerance levels.
Peng has designed the unit to employ three alert levels — green, yellow and red — based on an average of parts per billion recommendations from various health agencies. When the sensor turns yellow, it provides an alert to a smartphone app and it’s recommended that you “open a window for ventilation”. If it turns red, meaning the tolerances have been exceeded, Peng says the user should “leave the area”.
The device can be built at relatively low cost and it seems fairly straightforward to do.
Using A 3D Print Emissions Sensor
But does this mean you should?
I’m all for getting more information about, well, everything, but there has to be a point. Information is not useful unless action can be taken based on that information.
In this case, an installation of this sensor or any similar system would be of limited use. The only actions that could be taken would be either: provide ventilation or filtration, or stop 3D printing.
This is why we simply suggest providing ventilation. You’re going to do it anyway, unless you would be willing to receive a “red” level alert and continue 3D printing.
Comments on the Hackaday post also point out that VOCs are not always harmful. You’ll easily get a super high reading if you evaporate any alcohol into the air, and that happens all the time in many places. There are other VOCs that are extremely toxic even in small amounts that might not be detected by this particular sensor. Finally, the sensor is not able to detect all VOCs, but instead only a reasonable set of VOC types. What if there is a VOC outside of its detection range? Green alert level.
I’m sure many people are curious about whether VOCs are present in their 3D printing setup, but in truth there is little value in that information. Just ventilate and take common sense precautions.