You’ll always want a unit with a tobacco smoke CADR at least 2/3 your room’s area. For example, a 10′ x 12′ room -120 square feet – would require an air cleaner with a tobacco smoke CADR of at least 80. If your room size is smaller, the unit will simply clean the air more often or faster. If you have ceilings higher than 8′, you’ll want an air cleaner rated for a larger room.
