Why? 14 to 20 hour days surrounded by death in 100 degree 99 percent humidity with no ac.
I recall the one time having to work on an old, defunct landfill with a respirator and tyvek suit on in the summer on the east coast. HOT!
After I saw some guy walking his dog in the same area as I was working, I would sneak gulps of fresh air and try to wipe off the fog from the face mask. Probably not a huge deal at an old landfill.
A big no-no in an Ebola isolation tent.