Carbon filters are used for trapping unwanted smells, toxic fumes and other volatile organic compounds (VOCs). When polluted air is pushed through the filter, the high surface area of the activated charcoal traps the unwanted gases. Carbon filters are not good for trapping particulate matter, such as PM2.5, and that’s why they should be paired with an HEPA filter to provide a complete filtration of your indoor air.
Please note: the carbon filter shouldn’t be used along with a HEPA on the Original as the air flow rate is not sufficient. It is possible to use just a Carbon filter on the Original (no HEPA filter) if you think you have a serious VOC problem.
Filter stacking order:
Not sure if you have a VOC problem?
You can run a “poor man’s VOC test” by sniffing the air where you air. If you can smell any plastics smells, or the kind of smells you get in a new car, off paint, or from new furniture, you may well have a VOC issue.