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What a useless article. How about some evidence and pointers to things that aren't? Humidity/pressure/temperature are actually the three measurements that pro

by bsder 4y ago

What a useless article. How about some evidence and pointers to things that aren't? Humidity/pressure/temperature are actually the three measurements that probably aren't a scam. The sensor chips you can get are generally well-calibrated and do what they say. Do read the datasheet, though: there are lots of ways you can screw them up (soldering them wrong, for example). The CO2, VOC and particulate sensors seem to be absolute snake oil, though. I have yet to buy any device that "senses" these that has any correlation to anything resembling reality. Which seems kind of stupid because CO2 and particulate sensors shouldn't be that difficult. Volatile organics, though, tend to be difficult as they have a lot of confounding factors. I'd really love to have a recommendation for something that's been validated that isn't $10K+.

_yb2s 4y ago
I agree... I have a bunch of cheap indoor air quality measuring devices, and they all consistently read temp, pressure, and humidity close together. My CO2 meter measures exactly what I'd expect -high levels with windows closed, correct outdoor levels with windows open. My cheap PM2.5 air quality meter reads almost exactly what I see in purple air when I take it outside. Basically, I purchased a bunch of diverse cheap air quality sensor products that I have verified all read correctly, and are not scams. I don't think this article is accurate.
ThrowawayR2 4y ago
Why not look at bare HVAC sensors used for office building air quality monitoring? - https://new.siemens.com/global/en/products/buildings/hvac/sensors/air-quality.html https://new.siemens.com/global/en/products/buildings/hvac/se... - https://buildings.honeywell.com/us/en/brands/our-brands/bms/field-devices/iaq-sensors https://buildings.honeywell.com/us/en/brands/our-brands/bms/... Granted, they're not meant for standalone use but at least you're not wondering whether the vendor is reputable or whether the sensor does what it says it does. For example, at a casual glance, the Siemens QPA2002D VOC and CO2 sensor seems to be available for <$500 and comes with a fairly comprehensive datasheet.

by bsder 4y ago

_yb2s 4y ago

I agree... I have a bunch of cheap indoor air quality measuring devices, and they all consistently read temp, pressure, and humidity close together. My CO2 meter measures exactly what I'd expect -high levels with windows closed, correct outdoor levels with windows open. My cheap PM2.5 air quality meter reads almost exactly what I see in purple air when I take it outside. Basically, I purchased a bunch of diverse cheap air quality sensor products that I have verified all read correctly, and are not scams. I don't think this article is accurate.

ThrowawayR2 4y ago

Why not look at bare HVAC sensors used for office building air quality monitoring? - https://new.siemens.com/global/en/products/buildings/hvac/sensors/air-quality.html https://new.siemens.com/global/en/products/buildings/hvac/se... - https://buildings.honeywell.com/us/en/brands/our-brands/bms/field-devices/iaq-sensors https://buildings.honeywell.com/us/en/brands/our-brands/bms/... Granted, they're not meant for standalone use but at least you're not wondering whether the vendor is reputable or whether the sensor does what it says it does. For example, at a casual glance, the Siemens QPA2002D VOC and CO2 sensor seems to be available for <$500 and comes with a fairly comprehensive datasheet.