Why it matters
The Blueair Signature SP1i Air Purifier is a compact / desktop air purifier that its maker rates for 250 square feet.
At the usual 4.8 air changes an hour and an 8-foot ceiling, a 250-square-foot rating implies about 160 cubic feet of clean air a minute. In a 12-by-15-foot bedroom that would turn the air over roughly 7 times an hour.
Filtration: Activated Carbon. Quietest setting, per the listing: 50 db. Power draw: 20 watts.
Price-wise it sat in the middle third of the 30 compact / desktop models we cover when we checked; the button shows today's price.
It qualifies for our lists Best Air Purifiers for Apartments and Dorms, Best Air Purifiers for Home Offices, Best Air Purifiers for Multiple Pets, where it is ranked against every model that meets the same rule.
Its rated room size of 250 square feet is one of the smallest ratings we cover: 13 of the 152 purifiers with a stated figure come in lower, and the range runs from 62 square feet to 4,800 square feet.
Compared with the Blueair Blue Pure 511i Max: rated room size 250 square feet here vs 237 sq ft.
The listing gives a weight of 5.64 pounds.
Who it's for, and who should skip it
Good fit if
- Rooms up to about 250 square feet
- Allergy season
Look elsewhere if
- Whole-home filtration on its own
- Rooms far larger than its rating
Pros and cons
Pros
- Rated for 250 square feet
- Low setting 50 db
- 20 watts draw
Cons
- Filters are an ongoing cost
- Size to the room at 4.8 air changes per hour
Limitations to weigh
- Specifications are the maker's or seller's own figures; check fit against your equipment's model number and the actual size.
Specifications
The bracket shows where each figure comes from.
| Model number | 4512311000 | Retailer |
|---|---|---|
| Room coverage | 250 square feet | Retailer |
| Noise (seller) | 50 db | Retailer |
| Wattage | 20 watts | Retailer |
| Filter type | Activated Carbon | Retailer |
| Filter class | AirPurifierFilter | Retailer |
| Particle size captured | 0.1 micron | Retailer |
| Product weight | 5.64 pounds | Retailer |
| Unit count | 1 Count | Retailer |
Alternatives worth comparing
More air purifiers we cover
- Blueair Blue Pure 411i+ Max $118.99
- Coway Airmega 200M $229.99
- Alen BreatheSmart 45i $449
- FreAire HAP605 Air Purifier
- AirDoctor AD4000 $679
All air purifiers, compared in one table · Every Blueair product we cover
Final verdict
A sensible choice for rooms up to about 250 square feet. Confirm the model it fits before ordering.
Where to buy
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