Coronavirus Avoid wearing coronavirus face masks with vents, valves, CDC says in updated guidance Valves make masks a bit more breathable but 'don’t do anything in terms of filtering' ...

Q: What’s your take on the Ecovent dryer vent? I understand the need for a vent that effectively keeps out cold air, but I’m concerned about the foam ball that acts as a valve inside this product.

"Masks with one-way valves or vents allow air to be exhaled through a hole in the material, which can result in expelled respiratory droplets that can reach others," the CDC says.