I have gone a while without an air quality meter / VOC meter and it looks like I’ve been missing something all this time.
I’ve been working on a graphing VOC meter to see how good or bad my own print room was doing. I mostly print PLA and PETG so should be ok, right?
I’m using the Sensiron SGP41 VOC sensor and an Adafruit MagTag to collect and display VOC data and it’s kind of startling. The data is processed using Sensiron’s own algorithm to kind of normalize results. The VOC data out of that algorithm ranges from 0 to 500 “index units” with a 100 score taken as “clean air”.
For this data capture I put the sensor right next to the side of my X1C with the door open while printing a part in white Bambu Basic PLA. 1 hour and 10 minutes print. The VOCs reported by the sensor went almost half scale and lasted hours longer than the print took.
Just one print with PLA but looks like even though PLA doesn’t have much odor, it’s no slouch at putting out fumes. Likely fairly benign with PLA but something is definitely there that VOC sensors respond to. VOC sensors need to be calibrated for what they may sense and this is uncalibrated.
For whatever it’s worth. Unfortunately VOC sensors don’t say what they are responding to but the major emissions from printing PLA are a chemical called “lactide” (3,6-dimethyl-1,4-dioxane-2,5-dione), with smaller amounts of IPA and acetaldehyde. Lactide is non-sensitizing but is listed as a respiratory and eye irritant.