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Air purifier size chart
A printable air purifier sizing chart using AHAM's two-thirds rule, with the higher CADR for wildfire smoke.
What is on this chart
AHAM's two-thirds rule: the CADR should be at least two-thirds of the room's area in square feet.
| Room | Area | Minimum CADR (2/3 rule) | For wildfire smoke |
|---|---|---|---|
| 10 x 10 ft | 100 sq ft | 67 | 100 |
| 10 x 12 ft | 120 sq ft | 80 | 120 |
| 12 x 12 ft | 144 sq ft | 96 | 144 |
| 12 x 14 ft | 168 sq ft | 112 | 168 |
| 14 x 16 ft | 224 sq ft | 150 | 224 |
| 16 x 20 ft | 320 sq ft | 214 | 320 |
| 20 x 20 ft | 400 sq ft | 267 | 400 |
For pollen allergies , check the pollen CADR on the box as well as the smoke figure. A bigger CADR than you need just cleans the air more often.
