Blueair Blue Signature Air Purifier: CADR, Noise, Coverage & Specs
Last verified: Aug 22, 2026
Aug 2026
Quick verdict
The Blueair Blue Signature is best suited to large rooms where high airflow, quiet minimum operation, and app control are priorities. Its 455 CFM smoke CADR supports about 705 sq ft at approximately 4.8 air changes per hour. Buyers should separately evaluate filter cost, maximum-speed noise, and Blueair’s HEPASilent filtration before deciding.
Best for
- Large open rooms
- Low-noise minimum settings
- App or Wi-Fi control
Consider alternatives if
- You need a verified maximum-speed noise figure
- Filter replacement interval or cost is a deciding factor
- You are planning around the manufacturer coverage claim rather than CADR-based room size
Verified strengths
- 455 CFM smoke CADR (~705 sq ft at ~4.8 ACH)
- 23 dB published minimum noise
- HEPASilent filtration (as published)
- Wi-Fi or app control
Verified limitations or missing information
- Maximum-speed noise is not in our sources
- Filter replacement interval is not verified
Blueair Blue Signature overview
The Blueair Blue Signature is a large-room air purifier with a smoke CADR of 455 CFM. Based on our CADR-based room-size method, it is suitable for approximately 705 sq ft. It includes HEPASilent filtration, 23 dB minimum noise, and Wi-Fi or app support.
- Smoke CADR
- 455 CFM
- Recommended room size
- 705 sq ft
- Claimed coverage
- 3385 sq ft
- Minimum noise
- 23 dB
- Filter type
- HEPASilent
- Wi-Fi / app
- Yes
- Power
- 42 W
- Dimensions
- 17.2 × 15.5 × 15.5 in
- Weight
- 13.2 lb
- Last verified
- Aug 22, 2026
Blueair Blue Signature CADR and room size
Recommended room size is about 705 sq ft (CADR × 1.55). That is approximately 4.8 air changes per hour in a room with an eight-foot ceiling. The manufacturer figure of 3385 sq ft corresponds to about 1.0 air change per hour at the same ceiling height and is shown separately. Our recommended room size uses approximately 4.8 air changes per hour with an eight-foot ceiling. Manufacturer coverage figures may use a lower air-change rate and are shown separately.
The manufacturer coverage claim is higher than 3× CADR, so it is not used for ranking.
Blueair Blue Signature noise level
Published minimum noise is 23 dB.
Maximum-speed noise is not in our sources.
Blueair Blue Signature filtration
Published filter type: HEPASilent.
Blueair describes HEPASilent as a combination of mechanical and electrostatic filtration. We do not independently verify particle-removal efficiency.
Filter replacement interval is not verified in our sources.
Blueair Blue Signature smart features
7 stages of filtration, 10x more odor removal, Smart VOC sensor, Dynamic display
Blueair Blue Signature specifications
- CADR (smoke)
- 455 CFM
- Recommended room size
- 705 sq ft
- Manufacturer claimed coverage
- 3385 sq ft
- Minimum noise
- 23 dB
- Filter type
- HEPASilent
- Power
- 42 W
- Dimensions
- 17.2 × 15.5 × 15.5 in
- Weight
- 13.2 lb
- Wi-Fi / app
- Yes
About Blueair air purifiers
Blueair models in this catalog are compared by CADR, recommended room size, noise, and filter type.
Blueair Blue Signature comparisons
Compared with the Blueair Blue Pure 211i Max, the Blueair Blue Signature has 5% higher CADR.
What is the CADR of the Blueair Blue Signature?
Smoke CADR is 455 CFM.
What room size is the Blueair Blue Signature suitable for?
About 705 sq ft at approximately 4.8 air changes per hour with an eight-foot ceiling.
How loud is the Blueair Blue Signature?
Minimum reported noise: 23 dB.
Does the Blueair Blue Signature have Wi-Fi?
Yes — app or Wi-Fi features are listed.
What filter does the Blueair Blue Signature use?
HEPASilent.
Methodology
Specifications are compiled from manufacturer documentation, product listings and other cited sources.
How we calculate recommended room size.
Sources
All air purifiers · Blueair air purifiers · Best air purifiers for allergies · Methodology