Hidden Costs of My Air Quality Monitors
Considerations when purchasing consumer air quality monitoring equipment
In our attempt to make better decisions, we must know more about the world around us. Air quality inside and outside can have a detrimental impact on health, both short-term and long. It seems every spring and summer, folks across the US take turns getting smoked out by massive wildfires — PNW, Rocky Mountains and the east coast have all had their turns this year.
One of the best sources of Air Quality Monitoring craftsmanship is AirGradient.com. In particular, I want to talk about this article, which focuses on the hidden cost of monitoring Air Quality. The article highlights some things to consider when choosing options for monitoring. The author, Achim Haug, lists the following points to consider when purchasing Air Quality Monitors: proprietary hardware, vendor lock-in, data ownership and life-time/self-repair.
I wanted to look at some of the sensors in my stack and evaluate how they stand up to this. For indoor air quality monitoring, I use the following devices (with affiliate links):
- Airthings 2930 Wave Plus - Radon & Air Quality Monitor (CO2, VOC, Humidity, Temp, Pressure)
- Airthings 2950 Wave Radon - Smart Radon Detector with Humidity & Temperature Sensor
- Nova PM Sensor SDS011 High Precision Laser pm2.5 air Quality Detection Sensor Module Super dust sensor
The Airthings Wave line is battery powered. If you’re flexible on placement, I would recommend getting plug-in AA battery placeholders so you don’t have to change batteries a few times a year.
Let’s investigate my consumer-grade monitors following AirGradient’s script:
- Do you have a subscription free way to send data directly to my own servers, eg. To home assistant via MQTT?
- Do I, as the owner of the monitor, have the full ownership of the data that I collect?
- Do you monetize the data that I provide to your platform?
- Do you share the air quality data with a public non-profit repository like openAQ for common good?
- Is your monitor easy to repair? Do you have a maintenance / repair manual?
- Do you offer spare parts for the monitor? At what cost and for how long?
Airthings 2930 Wave Plus & 2950 Wave Radon
- Do you have a subscription free way to send data directly to my own servers, eg. To home assistant via MQTT?
Yes. This is the way I use my Airthing devices, without using the app. I leverage their waveplus-reader git repo on my raspberry pi to read the sensor data and expose it as a REST sensor to Home Assistant and as a prometheus endpoint to be used as a data source in grafana. If you use the app, you can download the data, but I have not investigated programmatic solutions using Airthings’ servers. I would prefer my data not make it to their servers.
2. Do I, as the owner of the monitor, have the full ownership of the data that I collect?
Yes if I do it my way with waveplus-reader. No if you use the app, which is how most people are expected to use it.
3. Do you monetize the data that I provide to your platform?
According to their website they do not sell data to third parties. However, they have another website https://radonmap.com/. They may not sell the data, but they definitely use the data to try and sell more radon detectors:
radonmap.com uses Airthings sensors from around the world to show live radon levels, broken down by location and anonymized.
4. Do you share the air quality data with a public non-profit repository like openAQ for common good?
No, see 3. They do not share any data with any third parties. However, I am sure that someone could scrape (or maybe there is an API) the radonmap.com dataset.
5. Is your monitor easy to repair? Do you have a maintenance / repair manual?
No and No. I have had my Wave Plus since 2020 and experienced no noticeable problems. However, there are a lot of reviews about inaccurate readings which may be an indication that repair is needed. There are reddit posts about inaccurate readings and some negative sentiment about the accuracy of the product. Comments on reddit say the newer models have inferior hardware and the older models worked better (the ones I have). Regardless, I assume Airthings refurbishes the ones that it replaces through warranty. I think of this more like a $200 smoke detector, it becomes e-waste once the sensors become inaccurate.
6. Do you offer spare parts for the monitor? At what cost and for how long?
No. There are no spare parts to be used. I do not believe this device is intended for self-repair. I reached out to Airthings support about what the expected longevity of their sensors was and this was the response:
To answer your inquiry our Airthings device/sensor it doesn’t have an expiration date or estimated years for the end of life. For our device or sensor ideally, the device should work for a long period of time since the device was designed to get a long-term average for its measurements….
If your device is not working properly or it is indeed faulty, we will notify you as soon as possible and will be happy to offer you a variety of options for your satisfaction, including replacing it under warranty if necessary.
It is interesting to me that Airthings support will notify me if my sensors are degrading, not the other way around. Well, that’s not going to work since I am not sending them my data. Guess I will have to find out for myself, luckily for at least the Radon and CO2, I have multiple sensors for sanity checks.
Nova PM Sensor SDS011
- Do you have a subscription free way to send data directly to my own servers, eg. To home assistant via MQTT?
Yes, it’s just USB.
2. Do I, as the owner of the monitor, have the full ownership of the data that I collect?
Yes.
3. Do you monetize the data that I provide to your platform?
No.
4. Do you share the air quality data with a public non-profit repository like openAQ for common good?
No, but I could publish the data I get with this sensor to openAQ (but I don’t, it’s indoor and not useful).
5. Is your monitor easy to repair? Do you have a maintenance / repair manual?
Their datasheet is pretty comprehensive. I think it would provide someone savvy enough the information they need to fix a component on the board. I am going to go with a “Yes” for this one.
6. Do you offer spare parts for the monitor? At what cost and for how long?
I could not find any spare parts, but the monitors are rather cheap, and I think the board components are standard and could be found online. I think it likely that the fan could be replaced, but the custom housing and laser most likely couldn’t.
Conclusion
Trying to answer some of these questions about Airthings definitely opened my eyes and will change how I approach my next purchase. I initially assumed I would be able to find a PDF online with all the specifics about the sensors in my Airthings devices, but that was not the case. The sensors are proprietary. I have not had any noticeable problems with my Airthings devices, but I think when they do bite the dust I will seek a device and manufacturer with more openness with respect to data and hardware. As for the Nova PM Sensor, I would recommend it for anyone who is looking to monitor indoor particulate with a pretty straight-forward entry point. Thank you for reading.
