An army of do-it-yourselfers at the University of California, San Diego is building 250 homemade air purifiers for classrooms and labs around campus.

HEPA (High Efficiency Particulate Air) filters are amazing for removing unwanted airborne particles, and the best air purifiers usually have one - including one of our tried and tested favourites ...

The idea seems pretty simple, once someone explains it. The virus that causes the pandemic disease Covid-19 passes from human to human on tiny droplets of spittle, through the air.

Air filters made with the nanofiber material were found to block up to 90 percent of particles smaller than 2.5 microns, a category known as PM2.5 that are thought to be the most hazardous to ...