DIY Air Purifiers

DIY Air Purifier

Overview

This project documents the Corsi-Rosenthal box DIY air purifier design - a low-cost, highly effective approach to improving indoor air quality that emerged during the COVID-19 pandemic from collaboration between researchers and practitioners.

The Design

The Corsi-Rosenthal box uses readily available materials:

  • Four 20" MERV-13 filters forming the sides of a cube
  • A 20" box fan on top, pulling air through the filters
  • Cardboard sealing the bottom

Total cost: approximately $120-200 USD, with no special tools required.

How It Works

MERV-13 filters can remove about 85% of virus-laden particles from air. These devices deliver approximately 600 cubic feet per minute of filtered air to a room. For medium-sized rooms, one to three boxes can boost air changes per hour (ACH) to the 6 ACH minimum recommended by the Harvard School of Public Health.

Why It Matters

Improving indoor ventilation is crucial for reducing airborne pathogen transmission. For comparison:

  • Typical home rooms: less than 1 ACH
  • School classrooms (ASHRAE standard): ~3 ACH
  • Hospital patient rooms: 6 ACH
  • Hospital airborne isolation rooms: 12+ ACH

Resources Available

The project page includes:

  • Step-by-step build instructions
  • Performance testing methodology
  • Placement recommendations
  • Safety considerations for filter handling

To find out more, visit: Edge Collective - DIY Air Purifiers