Hiding beneath a full face mask - nothing to do with Covid 19

Hi, I am wondering if anybody has come across the wearing of a face mask as some form of comfort?  My 17 year old son, diagnosed with Aspergers wants to wear a mask to hide his face.  He has created a design which contains aspects of things he likes and wants to wear it when he is outside.  He starts college tomorrow and I am panicking.  Is this to do with Autism? Is it to do with problems he had at school (socialising with others and 'torturing' by teachers).  I want to let him be himself, but I am worried about the reaction of others - both staff and fellow students.

Any help info or suggestions?