Silicon Valley Mom & Dad
When it comes to face masks, the word "mandatory" never means mandatory. Face masks are just too harmful to actually be mandatory. They cause psychological, sociological, and of course biological harm. The more we go through mass masking, the more clear the studies are about how really awful the things are, and we've known since long before masking started, that they simply do not help to stop the spread of a respiratory virus and may even be harmful.
There is no question that they are harmful and I can't make an argument for how anyone can claim to be able to wear a face mask safely. Just like so many other parts of 2020, face masks have been goofy experimentation.
So what is one to do when encountered with a less well read person claiming authority over you and a knuckleheaded one at that? One just needs to push in the right places and say the right words to have your exemption honored. There is no exclusive secret formula. There are many.
It all comes do to your being able to understand the policy appropriately, invoking an exemption effectively, and saying yes or no honestly.
1.) Get a hold of the policy.
Somewhere there is a written policy. Hey a hold of it and read it. Until you read it, don't trust anyone else's reading of it. Read primary source works yourself all the time. Accepting secondary interpretations blindly is how people lie to you and manipulate you, and in accepting secondary or even tertiary rather than primary sources, you welcome manipulation in your own life. The following email may do the trick in getting you the policy.