3D printers got a lot of attention when DIYers leapt to action to address equipment shortages early in the pandemic, but some everyday items found in hardware stores played a big role, too.

Air-ventilation upgrades have been badly needed in U.S. classroooms since long before the pandemic. Low-tech filtration systems that cost about the same as a textbook per student can make a big difference.

Poor indoor air on tribal lands can cause a range of respiratory illnesses, including viral infections. Here's how people are fixing the problem while preserving traditional ways.

Replacing wood stoves is essential but won't solve the indoor air pollution epidemic on its own.

Being indoors with other people is a recipe for spreading the coronavirus. But removing airborne particles through proper ventilation and air filtration can reduce some of that risk.