I walk almost every morning with my wife and our little dog. Today was a bit blustery and cold, with the temp down to the high 20's and a moderate wind blowing. I dressed warmly, with a hat and gloves as well, but found that my face was freezing. Suddenly I remembered the paper surgical type face mask I keep in my jacket pocket for when I go into a store that requires customers to wear a mask, which lately seems like every store. I was amazed what a difference that paper mask made in terms of my comfort during the walk. Until my body fully warmed up I kept that mask on and was not bothered at all by the cold. So these masks really do work for some things, and are worth keeping in your pocket on a cold day. As to keeping me safe from a virus, well, who knows?