![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
I finally ordered a more portable CO2 monitor than the QingPing pro. Main choices seemed to be the Aranet4 or Vitalight Mini; while I have enough income to blow $250 on a single-purpose toy, I don't want to, so I tried the Mini.
Review that helped push me over, and guided my initial use: https://breathesafeair.com/vitalight-mini-co2-detector-review/
I was rather grumpy at first; I didn't understand its behavior. I think that it was reading around 100 PPM lower than the QP, and in my well-ventilated room, that often meant it was trying to go under 400. Per the review, I did multiple manual calibrations, in particular I reset _both_ monitors in the same place at the same time outside -- and in a cross-breeze, rather than right by the door where it's recessed, at first. That got them both yielding similar values, and plausibly low ones where they should.
Yesterday I finally took the Vitalight out for a walk (it's been raining a lot) and measured CO2 at the public library and in Safeway. Mostly in the 600-800 range; there was a burst of 3000 at the pharmacy counter, but I might have been breathing in its direction, and it's quite sensitive to that.
Is 800, or even 600, indicative of enough ventilation to be able to attend unmasked? I dunno. Maybe, in a quiet area. In a talkative area, less so.
Related paper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8043197/
and spreadsheet https://docs.google.com/spreadsheets/d/16K1OQkLD4BjgBdO8ePj6ytf-RpPMlJ6aXFg3PrIQBbQ/edit#gid=519189277
How does a $40 sensor manage to compete with a $250 sensor?
Cheaper brand of NDIR, with +/- 50 ppm instead of +/- 30.
Doesn't measure pressure or temperature or humidity.
Doesn't keep a record of readings or connect to wifi or have an app.
The Aranet was actually just $150 before the pandemic, so 40% of the price seems to be profit-taking...
The review complains about a weekly automatic recalibration, with the advice of taking the sensor out for a walk at least that often, otherwise it may take a high indoor baseline as '400'.
Anyway, I'm fairly happy with it. I figure it 'only' having 8 hours of battery life, and even the recalibration thing, might be avoidable by leaving it off except when I go somewhere, which isn't that often.
Review that helped push me over, and guided my initial use: https://breathesafeair.com/vitalight-mini-co2-detector-review/
I was rather grumpy at first; I didn't understand its behavior. I think that it was reading around 100 PPM lower than the QP, and in my well-ventilated room, that often meant it was trying to go under 400. Per the review, I did multiple manual calibrations, in particular I reset _both_ monitors in the same place at the same time outside -- and in a cross-breeze, rather than right by the door where it's recessed, at first. That got them both yielding similar values, and plausibly low ones where they should.
Yesterday I finally took the Vitalight out for a walk (it's been raining a lot) and measured CO2 at the public library and in Safeway. Mostly in the 600-800 range; there was a burst of 3000 at the pharmacy counter, but I might have been breathing in its direction, and it's quite sensitive to that.
Is 800, or even 600, indicative of enough ventilation to be able to attend unmasked? I dunno. Maybe, in a quiet area. In a talkative area, less so.
Related paper https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8043197/
and spreadsheet https://docs.google.com/spreadsheets/d/16K1OQkLD4BjgBdO8ePj6ytf-RpPMlJ6aXFg3PrIQBbQ/edit#gid=519189277
How does a $40 sensor manage to compete with a $250 sensor?
Cheaper brand of NDIR, with +/- 50 ppm instead of +/- 30.
Doesn't measure pressure or temperature or humidity.
Doesn't keep a record of readings or connect to wifi or have an app.
The Aranet was actually just $150 before the pandemic, so 40% of the price seems to be profit-taking...
The review complains about a weekly automatic recalibration, with the advice of taking the sensor out for a walk at least that often, otherwise it may take a high indoor baseline as '400'.
Anyway, I'm fairly happy with it. I figure it 'only' having 8 hours of battery life, and even the recalibration thing, might be avoidable by leaving it off except when I go somewhere, which isn't that often.