Some indoor weather stations keep track of CO<sub>2</sub> levels, furthermore there are some mobile, commercial air quality monitors such as the [[Plume Labs Flow]].
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Some indoor weather stations keep track of CO<sub>2</sub> levels, furthermore there are some mobile, commercial air quality monitors such as the [[Plume Labs Flow]]. Researchers are always making new devices that are not available to the market yet.<ref>https://www.sciencedaily.com/releases/2022/04/220406101734.htm</ref>