Mask leakage

I'm a little confused over leakage rates. My Australian made Resmed Autoscore which seems to be similar to the US Resmed Elite II, displays mask leakage in L/s (the machine is set for an Activa mask) and the leakage is usually somewhere between 0.2 and 0.48 L/s.

But I've noticed in this forum that leakage rates are usually given in L/m and some report that their leakage is 0.0 L/m.

If you convert my figures to L/m, my leakage is abysmal by comparison and yet I am rarely aware of any leaks from the Activa compared to the Quattro which leaked like a sieve around the eyes.

I'm unsure as to how to solve my quandary but a good starting point would be to ask if US Elite II machines really report in L/m.

My understanding is that the Resmed machines report the excess 95 % ile leak rate in l/sec based on the mask in the menu.

Thus a 0.2 leak rate on the screen corresponds to a 12 l/min leak rate in excess of what would be expected. For example if the mask was a Swift II and the pressure was 12, then the expected leak would be 37 so a reading of .2 would correspond to a 95 %ile leak rate of 49 l/min.


Pressure
(cm H2O)
Flow
(L/min)
4 20
8 29
12 37
16 43
20 49

from page 11 of :
http://www.resmed.com/us/assets/documen ... er_eng.pdf

My understanding is that the Resmed machines report the excess 95 % ile leak rate in l/sec based on the mask in the menu.

Thus a 0.2 leak rate on the screen corresponds to a 12 l/min leak rate in excess of what would be expected. For example if the mask was a Swift II and the pressure was 12, then the expected leak would be 37 so a reading of .2 would correspond to a 95 %ile leak rate of 49 l/min.

Many thanks for the speedy reply even though it makes my true leakage look like a disaster (and I'd merely thought they were abysmal). I'll go off and look at the linked document now but again, thanks.

Hi Capers: The mask I have is a Quattro. There is a chart which shows Leaks Per Minute. It shows what pressure your set at-and a graph with a curve line-anything below that # is not considered a leak by that mask Co. My pressure is set at 13 and on the graph and the leak rate is 43, I checked my leak rate on my machine and it was 31 So as best I know--I'm below the 43--so that should be good. All masks have this, just depends on what kind of mask you have.It's in Leaks per minute.
I think I got this right, Wufman (Den) helped me with this last week. Thanks, good luck, Larry

Hi all

Well, that is my first check out to your phorum! We are a group of volunteers and starting a brand new initiative in a regional community in the exact same niche. Your phorum supplied us valuable information to work on. You have done a marvellous task!