As you already know, I receive messages from readers of my blog almost every day. Their most common question is which air quality monitor should they choose. Most of the time in their message, they tell me that they go through Amazon to find a product, but they are confused from their reviews.
Carbon Dioxide (CO2) Monitors are a big hit nowadays due to the pandemic and because they are great tools at helping us understand indoor ventilation in order to mitigate the spread of the virus. Many new CO2 monitors pop up every day like mushrooms. Are they good, well …. you have to be careful!
No offense to Amazon or AliExpress or Facebook but most of their products are garbage for two reasons. Firstly, they are cheap products that come from China but without any quality control. Apple products come from China too, but Apple controls the quality of the shipping products. I have reviewed some cheap air quality monitors here on the blog just to justify their low price tag. Secondly, companies that sell these products don’t offer any kind of support nor updates. If the product has a small bug, you will stick with it forever. Many times the language they come with is badly translated or they come in Chinese if you are not careful enough during the purchase process.
Another big problem with Amazon reviews is that sellers of the products pay people to give a positive review, read this article from The Verge here. As you can understand that makes the star system very unreliable.
Moreover, when you type “air quality monitor” on Amazon’s search engine, it will recommend you a product based on their agenda, which is the product that will offer them more money, and most likely it will be a sponsored product, like on the example above. I would never recommend someone to buy one of these three products. They don’t even have a brand name!
Don’t get me wrong respectable companies sell air quality monitors on Amazon too, but the average buyer cannot distinguish which products offer support and which ones don’t.
For the love of God, I have seen Schools and Businesses buying cheap CO2 monitor that end up in a drawer or closet because they are not able to keep a log file with the CO2 concentrations, so teachers and employees had to manually write the concentrations in a notepad.
If you want to buy an air quality monitor from Amazon, do it once you have chosen the products from unbiased sources. Avoid cheap products as their life span is unknown and very limited. Buy quality products from an ethical background company. Think wise about the sensors/services that will serve you the most and not opting for the one with the most sensors.
FIY, some DIY CO2 monitors that use quality sensors are better than the generic CO2 available on Amazon.