SIBATA SCIENTIFIC TECHNOLOGY LTD.

PM2.5/CO2 Monitor　PCX-1

It can confirm the concentration of carbon dioxide in the air in the living environment and the concentration of fine dust of approximately 2.5 μm or less in diameter in the air.
If there is insufficient ventilation in the room and there are many people, the carbon dioxide concentration in the room air rises, so it is useful as an indicator of good ventilation and density of people.