Shirts are required in my gym, and they have spray bottles of disinfectant scattered throughout. You are supposed to spray down the machine when you are done, and if you are caught not doing so, they can technically kick you out. I haven't seen them go that far yet, but even so, I always spray them down before and after I use them. It's just the right thing to do, kinda like putting the damn plates back on the racks after you are done with them. God I hate it when the squids leave them laying around.