r/crboxes

1.7K archived posts · Apr 2023 – Sep 2026

CR Boxes

r/crboxes

CR boxes are DIY (or buy) air purifiers that are much more efficient, affordable, and quiet than standard air purifiers. Show off your CR boxes, share tips on building them, and help reduce the transmission of Airborne diseases to end the ongoing Covid/SARS2 Pandemic. CR boxes stands for: Corsi-Rosenthal boxes CADR stands for: Clean Air Delivery Rate CFM stands for: Cubic Feet per Minute. Also referred to as airflow, the CFM is how much air a fan moves. Learn more at https://itsairborne.com

Created Apr 21, 2023

4.3KMembers (last snapshot)

1.7KArchived posts

A subreddit to learn about Corsi-Rosenthal Boxes, the affordable and efficient DIY air purifier. Show off your custom CR Boxes, share tips and tricks on ensuring everyone is breathing Clean Air and help reduce the transmission of Airborne diseases to end the ongoing SARS2 Pandemic.

CR Box = Corsi-Rosenthal Box

CADR = Clean Air Delivery Rate

ACH = Air Changes per Hour

Corsi-Rosenthal boxes is a design for a do-it-yourself air purifier that can be built comparatively inexpensively. It was designed during the COVID-19 pandemic, with the goal of reducing the levels of airborne viral particles in indoor settings

CADR is a measurement of the clean air volume that a purifier can provide in a fixed amount of time – ultimately a measurement of speed.

ACH is a calculation of how many times per hour the entire volume of air in a given space is replaced with supply and/or recirculated air.

Resources: https://itsairborne.com/

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