Calibrating PM2.5 sensors looks difficult. Relative humidity, temperature, different mixes of inorganic and organic aerosols, probably air pressure, integration times -- lots of dimensions.
PALMA[1] has a lot of work.
Air quality monitors: paying more does not get you more accuracy
11–20 of 218 posts
Re: Air quality monitors: paying more does not get you more accuracy
#12I bought a fairly expensive air quality monitor. Accuracy wasn’t what caused me to go with a more expensive model. I wanted CO2 readings, which most models under $200 don’t provide.
I suspect I know exactly which one you bought ;)
I wish I could find a good source for "outside CO2 levels" as I think they've been elevated but I have no way to prove it (beyond my indoor sensor showing high).
Re: Air quality monitors: paying more does not get you more accuracy
#13I bought a fairly expensive air quality monitor. Accuracy wasn’t what caused me to go with a more expensive model. I wanted CO2 readings, which most models under $200 don’t provide.
I suspect I know exactly which one you bought ;) I wish I could find a good source for "outside CO2 levels" as I think they've been elevated but I have no way to prove it (beyond my indoor sensor showing high).
Aranet4 is the way to go.
Tried going cheap and getting a bunch of Vitalights later as additional monitors but ended up finding out that their results were all over the place.
Returned the Vitalight. Kept the Aranet4.
I do have plans to build a few Airgradients when I have time.
Re: Air quality monitors: paying more does not get you more accuracy
#14I bought a fairly expensive air quality monitor. Accuracy wasn’t what caused me to go with a more expensive model. I wanted CO2 readings, which most models under $200 don’t provide.
I suspect I know exactly which one you bought ;) I wish I could find a good source for "outside CO2 levels" as I think they've been elevated but I have no way to prove it (beyond my indoor sensor showing high).
Airthings! It’s great.
Re: Air quality monitors: paying more does not get you more accuracy
#15I bought a fairly expensive air quality monitor. Accuracy wasn’t what caused me to go with a more expensive model. I wanted CO2 readings, which most models under $200 don’t provide.
Airgradient's kit has CO2!
Re: Air quality monitors: paying more does not get you more accuracy
#16They probably all use the same Taiwanese component
Re: Air quality monitors: paying more does not get you more accuracy
#17Author here. I wrote this article a few weeks ago after discovering that a well known air quality monitor in the market that retails for more than USD 1000 actually uses a PM module that costs less than USD 20. Often people assume that the more expensive, the better but as you can see in the article this is often not the case -especially when it comes to the accuracy of the monitor. If you are looking for an open sou…
While I admire the efforts of the SC-AQMD, and generally agree with the article, using R2 from a higher-end, but not quite perfect instrument, can be quite misleading, and is not a great indicator of actual sensor performance. Also, there are a lot of potential improvements in sensor tech, but instead almost everyone is relying on the same cheap sensor modules instead of innovating, which have have pretty bad deficie…
The R2 is between the tested monitor and the AQMD reference instruments (BAMs and Grimms). They also test if the two reference instruments agree with each other before calculating the correlation to the tested monitor.
So I believe their testing method is quite accurate.
Re: Air quality monitors: paying more does not get you more accuracy
#18Author here. I wrote this article a few weeks ago after discovering that a well known air quality monitor in the market that retails for more than USD 1000 actually uses a PM module that costs less than USD 20. Often people assume that the more expensive, the better but as you can see in the article this is often not the case -especially when it comes to the accuracy of the monitor. If you are looking for an open sou…
The same is true of digital bathroom scales. In fact almost all consumer grade digital scales have “fake accuracy” built into the firmware that ensures the same exact weight shows up when you step on the scale twice in a row, even if you pick up e.g a quarter-pound weight in your hand the second time
Re: Air quality monitors: paying more does not get you more accuracy
#19Author here. I wrote this article a few weeks ago after discovering that a well known air quality monitor in the market that retails for more than USD 1000 actually uses a PM module that costs less than USD 20. Often people assume that the more expensive, the better but as you can see in the article this is often not the case -especially when it comes to the accuracy of the monitor. If you are looking for an open sou…
The same is true of digital bathroom scales. In fact almost all consumer grade digital scales have “fake accuracy” built into the firmware that ensures the same exact weight shows up when you step on the scale twice in a row, even if you pick up e.g a quarter-pound weight in your hand the second time
Yes, but do you(or someone else) have a recommendation of which scale does not do this? Something that's not consumer grade, but not "enterprise cost"
Re: Air quality monitors: paying more does not get you more accuracy
#20Author here. I wrote this article a few weeks ago after discovering that a well known air quality monitor in the market that retails for more than USD 1000 actually uses a PM module that costs less than USD 20. Often people assume that the more expensive, the better but as you can see in the article this is often not the case -especially when it comes to the accuracy of the monitor. If you are looking for an open sou…
Out of interest what are your thoughts on the Aranet4? (other than it's quite high price of course).