Allen,If you look at the graph, there are ALWAYS leaks at 25 and higher and there is usually a baseline amount betwewen 30 and 40 where the line stays very straight. Should that baseline be near zero?
Each mask has a built in leak rate, exhaust, CO2 washout, whatever you care to call it. For the Comfort Gel you are using the published leak rate is 23.4 lmp at a pressure of 8 and 26.7 lpm at a pressure of 11. I don't exactly know how it would work with the bipap but let's say you were using a steady pressure of 11. Your "baseline" would be 26.7. So anything much over that would be actual leaks. I don't know how tight the manufacturing tolerances are, but I'm sure there would be some minor differences from mask to mask.
Brian