Equipment
Air Gradient ONE
We utilize the Air Gradient ONE Indoor Air Quality (IAQ) monitor to collect real-time data on indoor environments. The monitors continuously measure key air quality indicators, including levels of particulate matter (PM) and volatile organic compounds (VOCs).
The Air Gradient ONE is a low-cost monitor that connects to WiFi to quickly relay data. It features an onboard readout that community members can read at a glance to understand their air quality in real time. While science already backs up the use of CR Boxes for the removal of particles in indoor environments, these cost-effective air quality monitors aide with surveilling the efficiencies of the CR boxes in minimizing the spread of pollutants in indoor environments. In addition to helping track the effectiveness of indoor remediation strategies, the Air Gradient ONE monitors assist with indicating when air filters need to be changed.
Implementing technology from SenseAir, Sensiron, and Plantower, all of the air quality monitors go through rigorous multi-step calibration procedures at Air Gradient, and are then validated by our team to maximize accuracy and function.
Corsi-Rosenthal (CR) Box
The Corsi-Rosenthal (CR) box is a cost-effective, do-it-yourself air filter used to increase particle removal in indoor spaces. The CR box was developed in 2020 by Jim Rosenthal in response to COVID-19 and builds on Richard Corsi’s idea of using multiple filters and a box fan to improve the efficiency of homemade air filter designs. Composed of 4 HVAC filters, 1 box fan, duct tape, and cardboard, the CR box is an accessible solution that can be built using items found in most stores.
CR boxes have proven to efficiently filter out microscopic particles in the air by increasing airflow in enclosed spaces. Communities with a higher risk for wildfires are particularly vulnerable to air pollution that travels to indoor spaces, which is worsened by congestion in public areas without proper air circulation. Because of their low cost, CR boxes can be a swift solution in response to wildfire smoke.
Interested in building your own CR box? Check out the tutorial linked below for steps on how to build one:
The CR Box in Action
The image at right depicts CR box filters before and after providing air filtration for up to approximately 8 months. The four HVAC filters that form the sides of the box promote clean air until they start looking like the box on the right. The filters can, however, be swapped out easily. Reusing the same box fan and cardboard cutouts, new filters may be easily added to refresh the CR box.
