I own a Fujitsu PDS-4203 42" (second gen). I have read many articles on Plasma TV's. My set is fairly 'low end' compared to the ones you can get nowadays. I have read quotes that a Plasma TV will last, at optimal level, for just over 5 years but that's with 24 hour continuous use, 7 days a week, 365 days a year (that's 8760 hours per year or 43800 hours in it's lifetime. And that is continuous use aswell) Now I don't know about you, but I don't use mine for anywhere near that amount of time. If you take into consideration that you might use your Plasma for 5 hours a day (that's alot!!!), every day of the year. Then that works out at only 1825 hours per year or 9125 hours in the same 5 year period.) Which gives you a life span of nearly five times as much. 25 YEARS!!!!!! Now even your normal Joe in the street is bound to change their TV at least once in that amount of time. So in answer to your question (phew!!!!!) I doubt you'll ever have need to 'recharge' the gas in your Plasma. Hope this helps!