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Air Flow - showing you when your central air system is on and when it's off
Particles (Particulate Matter) - displayed in both counts per meter cubed and microgram per meter cubed
Chemicals (Volatile Organic Compounds)- displayed in both counts per meter cubed and microgram per meter cubed
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Carbon dioxide
Carbon monoxide
Mold
Radon
Check out this article on what causes poor air quality, and this article on what you can do to improve it What Causes Poor Air Quality?, and How do I improve poor air quality in my home? for more info.