HELP?! What *IS* the correct magic number for a leak to be too high?

[Peter_C]

Color me confused?

Leaks suck, I know this. The less leaks you have, the better it is, I know this as well...

But, what is considered to be the magic number that we need to keep our leaks *BELOW*??

And, is it "L/s" or "L/m" (in other words, liters per second, or liters per minute)??

My machine reports L/s (liters per second), but that's OK, I can do the math to figure out L/m (liters per minute) too

I've been reading and reading, and thought I had read it was 24L/m. But then, I just read a post which stated, 24L/s - a big difference!

For a Resmed machine, how large must a leak be (or stay at) for the machine to have a possible issue dealing with the leak, and/or, cause a risk of possible incorrect data? In other words, can someone simply give me a reasonably correct number to have as a *rule* or goal to attempt to stay under please?

Also - a two-part question? Where can I find what the nominal leak rate is for a given mask, and, is there a way (or a need) for us to tell our machine about the mask so that it can handle the normal/nominal leak rate created (on purpose) by said mask?

Thanks~!!

[zonk]

S8 report leaks L/s ........... S9 reports leaks L/m
0.4 L/s = 24 L/m

Both machines subtract intentional leak from total leak and reports unintentional leak

For this reason, you need to tell the machine type of mask using so it can work out unintentional leak
ResScan leak graph shows a red line at 24 L/m (0.4 L/s)
ResMed consider leak below the red line an acceptable leak

[Peter_C]

Thank you, and just to make triple sure I understand; Whatever leak rate is listed on the LDC screen of my machine, is *after* the machine has already subtracted what it thinks is the intentional (leak rate caused by exhaust port of mask), and is only showing me what it thinks is the unintentional leak rate? Correct?

Out of the available options for mask, I've chosen 'standard' mask.

[robysue]

But, what is considered to be the magic number that we need to keep our leaks *BELOW*??

And, is it "L/s" or "L/m" (in other words, liters per second, or liters per minute)??

My machine reports L/s (liters per second), but that's OK, I can do the math to figure out L/m (liters per minute) too

Resmed machines that are of the S8 vintage or earlier report leaks in L/sec and the Red Line for Large Leaks is drawn at 0.4 L/sec.

Resmed S9 machines (the current generation) report leaks in L/min and the Red Line for Large Leaks is drawn at 24 L/min.

For those who don't want to do the math: 0.4 L/sec = 24 L/min

To further clarify the issue:

Resmed machines report ONLY the excess leak. Hence there is NO need for a Resmed machine user to need to know the intentional leak rate for his/her mask. (That's why there is a mask setting on the Resmed machines---it's there to tell the machine how much to subtract off the raw leak rate data.) The intentional leak rate has already been subtracted from the leak rate data before it is recorded onto the card and shown to the the user through the machine's LCD or through ResScan or SleepyHead.

So for a user of a Resmed machine, the ideal leak rate is 0.0 L/sec (if you're using an S8 or earlier machine) or 0.0 L/min (if you're using an S9 machine)

But to muddy the waters for just a bit: It's important for RESMED users to realize that when they're reading posts about leaks from Respiroinics users and from F&P users, these machines report total leaks, which include the intentional leak rate for the mask. A PR System One user will NEVER see a leak rate of 0.0 L/min because the intentional leak rate of the mask is being reported in the leak data. The ideal leak rate for a PR System One user is a leak rate right around the expected intentional leak rate for your mask at the pressure you are using.