This might be unlikely but here's an idea. During this time, I have my mom who is a nurse and my friend who is working for dietary at Elgin Mental Health center. They told me the shields they wear around their face can get really hot and it builds pressure on their foreheads when they work. How else could they do their job if the thing they're wearing protects them, but also hurts them? Plus, it can get really hot in those, and if they were air tight, having cool air inside can help prevent heating up and only they can feel it.