Any ideas what it could be? I can provide more details on all the things that aren't causing it if people have specific questions.
Any ideas what it could be? I can provide more details on all the things that aren't causing it if people have specific questions.
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solutionz: UV?
How would UV affect VOC counts, and why at night when there's no UV? That's meant as a serious question, it could well be something like that but I can't see how it would specifically be UV.
I've got LED lighting in the house but it's probably not that because the counts decrease over time when, with prolonged LED light exposure, you'd expect them to increase of that was the cause.
gzt: Sensor just installed?
vs installed for a long time, stable readings, and now this.
Had it for about a year. I never noticed the spikes until a month or two back.
And to anticipate the obvious question, there's nothing that changed a month or two back that I can think of. I thought it might be a new couch outgassing solvents, but you'd expect that to be worse during the day with warmer temps.
neb:solutionz: UV?
How would UV affect VOC counts, and why at night when there's no UV?
neb:
And to anticipate the obvious question, there's nothing that changed a month or two back that I can think of. I thought it might be a new couch outgassing solvents, but you'd expect that to be worse during the day with warmer temps.
JP:If your room is located and situated as such that it begins receiving the direct afternoon sun; and the UV is causing furnishings in said room to off gass it could account for such a situation (begins to raise 4-5pm and drops off in evening).
Ah, of course! So that's now made it the most plausible explanation, the room does indeed get direct sun after about 2pm, finishing about 5pm at the moment, and there were a few temperature peaks that correspond to the VOC peaks which would indicate a lot of sun that day. The winter sun angle could be the reason why it's appeared in the last month or two. It's also easily tested, I can keep the curtains (heavy blockouts) closed during the afternoon.
What VOCs does the sensor detect?
Big difference IMO between a constant near 1ppm if it's benzene or if it's methane.
What the outgassing is - could be anyone's guess - phthalates from vinyl, coalescing solvents (glycol ethers) in water-based paints, cleaning product residues etc, some relatively harmless - some perhaps cause for concern.
Fred99:What VOCs does the sensor detect?
It'll be a cheap MEMS sensor rather than something like a photoionization detector so it doesn't specify, it's just "VOCs" ("It's chunky soup" / "What's in it?" / "Chunks").
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