None of us love wearing masks, and we’re all looking for the most comfortable options. So, maybe you’ve wondered about those masks with the plastic valve near the nose – Is this the answer I’ve been looking for? Will a valve solve my mask woes?
Sadly, no. While a valve may make breathing a little easier, that valve might be spraying your germs all over at high velocity every time you exhale – defeating the purpose of even wearing a mask. (Which is why Delta Airlines banned face masks with exhaust valves from their flights.)
Valve filters filter the air you breathe in. But they don’t filter your exhaled breath at all. When you exhale through a mask with a valve, not only does your unfiltered breath escape, but the force of the exhalation against the small opening of the valve can create a high-pressure stream of germs being blown out into the surrounding air.
To understand this better, think about your kitchen sink setup. If you turn on the faucet, the water flows through the large-diameter spout under low pressure. But if you engage the sprayer, the same water flow gets directed through small holes that create a high-pressure stream that can spray across your kitchen (as anyone who’s ever playfully sprayed their kid or spouse knows).
Keep in mind that the main purpose of wearing a face mask is not to filter the air you’re breathing in, but to reduce the amount of your exhaled breath that gets into the environment. Masks are meant to stop any potential germs from reaching other people – but masks with valve filters defeat this important goal of face coverings. So, your best bet is to stick with your cotton face covering.