I was told
Temp between 72-80
Humidity under 40.
This seems pretty good for most all. I've seen shops down to 30-35% that worked well and had even seen shops up at 45-55% that worked well, but they are not the norm. I've seen one dryer cabinet that was being kept at 140 or more degrees. That's way way too hot and works against the screen. Bakes them rather than drying them. The room temp is not (as important) as keeping the humidity down). I've been in some rooms that were 60-65 degrees in winter but as long as you are drawing the humidity out, it's ok.