What's the safest mask to wear? Here's what doctor says

Masks are flying off store shelves once again, as mandates return to help stop the surge of COVID-19 cases.

At this point it's likely you've tried them all, cloth masks, surgical masks, KN95 masks, N95 masks, and a mix of some of those together. Masks with replaceable filters have gained in popularity too. But which one is the best and which one provides you the most protection?

"The best mask you can wear is actually not a surgical or cloth mask alone," says UCSF's Dr. Monica Gandhi.

Meaning that most of those we saw with masks on Wednesday in San Francisco were not wearing the best masks possible at a time when COVID-19 cases are surging due to new variants.

N95 masks are an option, not always the most comfortable, but one of UCSF's Dr. Monica Gandhi's top three picks. Unfortunately, when we went to the Home Depot store in Emeryville Wednesday, shelves were empty. Employees telling us they sold the last N95 mask hours ago.

"What we would prefer is that you use at least a surgical or medical grade mask," said one health officer at a multi-county COVID-19 mask meeting earlier this week. But we spoke with Jeremy Howard of Masks4all who says he doesn't recommend the surgical masks unless they are pulled in on the sides. Meaning the elastic is knotted together with the leftover loop going around your ears.

"They have bad fits like we've discussed and I'd say they're pretty much the worst option. I would avoid them and go with these," says Howard referring to a KN95 mask. Make sure you get one of those from a known company though because many KN95's can be knock-offs.

As for Dr. Gandhi's last two top mask picks, she says either a cloth mask with a filter because they are thinner and still provide the double blockage or a double mask.

"A combination of a surgical and a cloth mask," says Dr. Gandhi.

Cloth against your skin and surgical on the outside is what studies found added nearly a third more protection.

"From 65% blockage with one to up to 94% with two so it was significant," says Gandhi.