Why do I sign and add a thank-you card for every air quality monitor we sell?

More than a year ago, we started to put a small thank you card into each of the air quality monitors we sell.

It looks like this:

I’m signing every single card by hand and now a few thousand cards later, I am still doing it and I have no intention at all to stop.

Some people might not pay much attention to a simple thank-you card but for me it’s actually a big deal.


Every day, I’m thankful for the great community of thousands of people around the world that are using an AirGradient indoor or outdoor monitor. It’s an extremely positive community and we get so much great feedback from people all around the world. The open-design nature of the monitors enabled many people to voluntarily contribute to make the monitor better. There have been countless contributions on the hardware side as well as on the firmware side. Additionally, we were able to set up a global research network and the best air quality scientists are supporting us to make the monitor more accurate. The thank you card is a way to show our community how thankful we are for your contributions!


Signing the card makes me feel responsible for each single box we ship. It’s like I’m guaranteeing with my very name that it’s a good product. I’m making a promise to each of our customers that we have put all our knowledge and best quality into the design and manufacturing of your monitor. If I knew that there is even a small problem with the air quality monitor, I would feel I am betraying our customers. So for me signing the card is like approving every single shipment.


With increasing sales numbers, I’m signing more and more cards and I’m proud of every unit we sell because I strongly believe that open-hardware and open-data is a major benefit for the customer and the planet. When we decided to go fully open-hardware in 2022 and open-sourced our previously proprietary designs, we entered uncharted territory. We are currently the only major manufacturer for air quality monitors that is open-hardware and at that time we really did not know if that big decision would turn out to be a success or a disaster. So signing these cards really gives me a feel for the growth and popularity of our monitors and shows that it is possible to be fully open and successful at the same time.


As you can read in our manifesto, we want to make a positive impact with improved air quality monitoring. It is part of our core values and our foundation. The thank-you card is also a call to our community to join our efforts to make accurate air quality monitoring more accessible and affordable. Only together can we fight air pollution and create a healthier environment and hopefully we can inspire as many people as possible to join us!

That’s all for now. Please reach out to me if you have any comments.


PS: Forgot to say, signing these cards also sometimes makes me feel like a superstar… Who knows, maybe one day people will buy the monitors just for the thank-you card…

by Achim Haug
Nov 12, 2023

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