Fun fact, Vader's suit is purposefully designed to cause him pain and irritation, though he does not know this. The Emperor told him that the pain may never fade, sneaky Emperor is sneaky. The only time he can get any comfort is in his pod, as seen in this picture. It is a pressurized environment that allows him to survive and is the only place he can remove the suit without the worry of death.
yes, this is as seen in star wars episode 5.
This information is fascinating but as it is only coming to light now (or has it been around and I just haven't paid attention?) is the constant pain aspect of Vader's suit something that Lucas originally envisioned or was this someone else's reasonable contribution?