A large area of greater Los Angeles had unhealthy air Friday, due to particulate matter from large wildfires. Here are tips ...

All you need is a box fan, good air filters and some duct tape, and you're in business. NPR has previously posted a design and guide to building an air purifying cube known as a Corsi-Rosenthal ...

All you need is a box fan, good air filters and some duct tape, and you're in business. NPR has previously posted a design and guide to building an air purifying cube known as a Corsi-Rosenthal Box, ...