I know that many regs can be serviced and used for decades as personal regs, but what about professional use? Our dive team regs are 20 year old aqualung glacia’s. They can still be serviced so we still use them. They have the larger diameter primary reg lp port and seem to have problems needing replacement pieces more than i would expect out of my newer personal regs. Is anyone aware of a standard or just have advise on when it’s time for a professional department to consider new regs? Is there a timeframe in years, or just when they are too busted to reasonably service?