What Would You Do with the Indoor Air Quality HAT for Raspberry Pi

I'm currently running the Honeywell Particulate Matter SensorHoneywell Particulate Matter Sensor to detect for pm2.5 and pm10 levels in the apartment (I've got a project log for that in hackaday https://hackaday.io/project/174293-bleifying-a-honeywell-pm-sensor). This seems to be measuring something else: total volatile organic compounds (tvoc) and not only returns the raw values, but also some sort of air quality level based on a standard. The air quality level seems the most interesting because it already defines for you what "bad quality" means.

Unlike the HPMS though, I don't see any fan or application note regarding air flow recommendations nor orientation. So I'm guessing installation would rely on the passive movement of air around it?

I can't see well from the attached picture but I'm guessing the view is from the top and will sit on top of the pi, and helpfully extends the gpios. This however would likely interfere with common pi cases, or will require that the pi's case have a removable top (and not connect the top). Which might be problematic because the pi4 (almost always) requires a heatsink and a fan even during idle.

kmikemoo's use case (option 4 in the manual) is interesting and is probably the industrial application (especially since it seems it can operate with a very bare mcu, as it can automatically trigger a signal based on quality changes), but I'm just worried that since we can't really enclose the pi we might be subjecting it to a far more corrosive environment than necessary. We can of course use it with a far cheaper pi zero but the hat form factor (as opposed to the pHat) means the hat will overhang the pi zero. Then again, with the extra real estate we also get a relative humidity and temp sensor, which again points to Renesas' intention to have the hat be a comprehensive environmental sensor.

I've got mixed feelings, and like the others I'm looking forward to read the road tests (and depending on the results, might get the sensor to complement my HPMS)

I'm currently running the Honeywell Particulate Matter SensorHoneywell Particulate Matter Sensor to detect for pm2.5 and pm10 levels in the apartment (I've got a project log for that in hackaday https://hackaday.io/project/174293-bleifying-a-honeywell-pm-sensor). This seems to be measuring something else: total volatile organic compounds (tvoc) and not only returns the raw values, but also some sort of air quality level based on a standard. The air quality level seems the most interesting because it already defines for you what "bad quality" means.

Unlike the HPMS though, I don't see any fan or application note regarding air flow recommendations nor orientation. So I'm guessing installation would rely on the passive movement of air around it?

I can't see well from the attached picture but I'm guessing the view is from the top and will sit on top of the pi, and helpfully extends the gpios. This however would likely interfere with common pi cases, or will require that the pi's case have a removable top (and not connect the top). Which might be problematic because the pi4 (almost always) requires a heatsink and a fan even during idle.

kmikemoo's use case (option 4 in the manual) is interesting and is probably the industrial application (especially since it seems it can operate with a very bare mcu, as it can automatically trigger a signal based on quality changes), but I'm just worried that since we can't really enclose the pi we might be subjecting it to a far more corrosive environment than necessary. We can of course use it with a far cheaper pi zero but the hat form factor (as opposed to the pHat) means the hat will overhang the pi zero. Then again, with the extra real estate we also get a relative humidity and temp sensor, which again points to Renesas' intention to have the hat be a comprehensive environmental sensor.

I've got mixed feelings, and like the others I'm looking forward to read the road tests (and depending on the results, might get the sensor to complement my HPMS)

From the road test IDT ZMOD4410 Indoor Air Quality Raspberry Pi HAT

> The Avnet IDT ZMOD4410 Indoor Air Quality Raspberry Pi Hat is an evaluation, development and quick-prototyping tool

Well, that makes sense they didn't design it for deployment but more for evaluation, which does away with the issues of the hat form factor (and heat). Although it might still play a role during dev and eval; as Gough Lui mentioned, the heat from the pi (especially since the hat would likely interfere with any active cooling fans present) might distort some of the measurements being done.