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Corsi-Rosenthal Box Air Purifier Review

Tested using Methodology v1.0
Reviewed May 13, 2024 at 01:24 pm
Corsi-Rosenthal Box Picture
7.7
Pets
4.3
Bedroom
9.5
Air Purification

The Corsi-Rosenthal Box is a build-it-yourself air purifier. The original design was drafted by engineers Richard Corsi and Jim Rosenthal during the COVID-19 pandemic and is pretty basic, consisting only of four furnace filters duct-taped together and supporting a large box fan. Overall performance and feature sets can vary depending on what components you use. However, as long as you stick to using high-quality filters and a relatively potent box fan, your own build will return broadly similar results. We built our own Corsi-Rosenthal box using this guide.

Our Verdict

7.7 Pets

Our Corsi-Rosenthal Box is a good fit for pet owners. While it's exceedingly noisy and will likely be a source of anxiety for animals that are particularly sensitive to loud noises, it also does a fantastic job of trapping a variety of particle sizes, including pet dander.

Pros
  • Superb overall particle filtration performance.
  • Very high clean air delivery rate.
Cons
  • Very noisy.
  • No smart functionality or sleep mode.
4.3 Bedroom

A Corsi-Rosenthal Box might not be the best choice for use in bedrooms. Depending on your filters and fan, these can be large, ugly, and very noisy machines. They do a fantastic job of trapping most airborne particles and are highly effective in larger spaces.

Pros
  • Superb overall particle filtration performance.
  • Very high clean air delivery rate.
Cons
  • Very noisy.
  • No smart functionality or sleep mode.
9.5 Air Purification

Our Corsi-Rosenthal Box is fantastic for general-purpose air purification. While there's no carbon filter to help trap VOCs and odors, using a powerful box fan allows for highly efficient operation even in larger spaces, while high-quality MERV 13 filters effectively trap most airborne particles. That said, it's bulky, noisy, and lacks smart features.

Pros
  • Superb overall particle filtration performance.
  • Very high clean air delivery rate.
Cons
  • Very noisy.
  • No smart functionality or sleep mode.
  • 7.7 Pets
  • 4.3 Bedroom

Performance Usages

  • 9.5 Air Purification
  1. Updated May 07, 2024: Review published.

Differences Between Sizes And Variants

Since this is a build-it-yourself device, overall performance can differ depending on component choice. It's worth noting that we tested a single-filter variation of the Corsi-Rosenthal Box, and it returned a drastically different overall performance.

Compared To Other Air Purifiers

It can be difficult to compare a Corsi-Rosenthal Box to most commercially available alternatives out there; as we determined in our research and development process, this homemade solution is very effective when it comes to particle filtration specifically because it doesn't have to follow the trends that dictate normal air purifier design, like size, noise, and even aesthetics. If you plan on using a Corsi-Rosenthal Box in an area where none of those things are a significant factor, it's certainly worth building your own.

Test Results

perceptual testing image
Design
Design
Body
Height 29.3" (74.5 cm)
Width 20.5" (52.0 cm)
Depth 21.9" (55.5 cm)
Weight
9.0 lbs (4.1 kg)
Power Cord Length 72.1" (183.1 cm)
Wheels
No
Design
Display And Control
Filter Change Indicator
No
Air Quality Sensor Auto Mode
No
Remote Control
No
App
No
Display On/Off
No
Timer Function
No
Number Of Fan Speeds
3

The Lasko 20-inch box fan in our Corsi-Rosenthal box has a three-level fan speed adjustment dial.

Design
Filter Configuration
Filtration Layers
1 Stage
Activated Carbon
None

Our Corsi-Rosenthal Box's filter system consists of four 3M Filtrete 20x25x1 MPR 1900 Premium Allergen, Bacteria & Virus Smart Air Filters. These filters have an estimated lifespan of three months when used in a home furnace, air conditioning, or HVAC system; their lifespan in an air purifier will fall within a similar ballpark, depending on how often you run it. You can buy a set of four filters here

Performance
9.5
Performance
Particle Filtration
Air Cleaning Rate
791 m³/Hour
Average Final 0.3 µm Concentration
38 particles/L
1.5
Performance
Noise
Noise @ Lowest Fan Speed
51.7dBA
Noise @ Highest Fan Speed
67.3dBA