Rigorous study on masking - they don't work!

They already know masks don't protect against Covid.
What they don't tell you is how bad they are for your own health and well being. If you must wear one for work, exchange it out every 8hrs at a minimum.

"Wearing facemasks has been demonstrated to have substantial adverse physiological and psychological effects. These include hypoxia, hypercapnia, shortness of breath, increased acidity and toxicity, activation of fear and stress response, rise in stress hormones, immunosuppression, fatigue, headaches, decline in cognitive performance, predisposition for viral and infectious illnesses, chronic stress, anxiety and depression. Long-term consequences of wearing facemask can cause health deterioration, developing and progression of chronic diseases and premature death. "
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7680614/