I bought a Chinese indoor/outdoor air quality monitor [NEW JSM-131 CO]. It reports on: Carbon Monoxide (CO) Carbon Dioxide(CO2), Formaldehyde(HCHO), Volatile Organic Compounds (TVOC), plus has an Air Quality Index summary number.
It is powered by a Micro USB socket, I've seen it draw up to 300 mA when charging the internal battery, but once the internal battery is charged the current draw drops down to 180 mA.
I purchased mine for $35 on Ebay, but had to wait several weeks for it to ship from China. You can also find them from Amazon ranging from $40-$60 (such as the link below).
Amazon Affiliate link:
HEI LIANG AIR: [ Ссылка ]
