Start with the room where you will actually run your purifier. Floor area, ceiling height, open doorways and the fan speed you use all affect how much clean air your space needs.
Measure your space first
Multiply room length by width. A 15 ft by 12 ft bedroom is 180 sq ft. Include connected dining or living areas in an open-plan space. Bedrooms with closed doors should be assessed separately; a whole-home square-footage claim does not guarantee effective cleaning in every room.
Understand CADR and coverage
Clean Air Delivery Rate (CADR) describes particle-cleaning capacity. Higher CADR means more clean air under the stated test conditions. CADR does not measure odor or gas removal. The EPA air-cleaner guide explains sizing, airflow and the differences between particle and gas filtration.
| Model | CADR | Listed room range |
|---|---|---|
| Pawtent | 250 m³/h (about 147 CFM) | 320–430 sq ft |
| Pawtent Ultra | 500 m³/h (about 294 CFM) | 650–860 sq ft |
The listed room ranges do not specify an air-change rate. For a like-for-like illustration, assuming an 8 ft ceiling and 4.8 equivalent clean-air changes per hour gives approximately 230 sq ft for Pawtent and 460 sq ft for Ultra. These are calculations from published CADR values, not separately certified room ratings or sleep-mode performance.
Calculation: room area in sq ft = CADR in CFM × 60 ÷ ceiling height in feet ÷ equivalent clean-air changes per hour. Taller ceilings or a higher air-change target reduce the area served at that target.
Match performance to your daily routine
Published noise ranges are 23–55 dB for Pawtent and 23–58 dB for Ultra, measured at 1 meter. The lowest noise figure and maximum CADR should not be assumed to occur at the same fan speed. If you plan to use a quiet setting overnight, consider its airflow as well as its sound level.
Choose with confidence
Compare your room dimensions, the fan speed you can comfortably use, filter upkeep and replacement costs. Keep the air intake and outlet clear and follow the model's placement instructions. Air cleaning supplements source control and ventilation; it does not remove every pollutant.
Compare Pawtent models · Understand filter care and costs · Ask for product help