Need leak rates for Mirage Quattro FF mask

I cannot claim to be addled from lack of sleep any longer, but I don't seem to have the leak rates for my Mirage Quattro mask. I think the rates are available - some of you seem to have them - but I didn't get any documentation with my mask that gives me leak rates.

I assume I am *not* having any leak issues because I am consistently getting AIs of fewer than 2/hr (and HIs of between 2-3). However, I would like to know what the acceptable leak rates are for my mask.

Can anyone help? It feels like this is the last little thing I need to "understand" about my equipment.

You can download the Quattro's user's guide from the Resmed site but here they are:

At pressure of 4 its 22 LPM
at 8 its 32
at 12 its 41
at 16 its 48
at 20 its 54
You can interpolate for in between pressures and also they say the tolerance on those values is +/- 6 LPM
due to manufacturing variations

My pressure is 10 and I found out that by doing the teflon fix I lowered the leak rate by about 4 LPM from 37 to 33



Bill

MoneyGal wrote:but I don't seem to have the leak rates for my Mirage Quattro mask.
Can anyone help? .

Find the user guide here:

http://www.resmed.com/en-us/products/se ... _multi.pdf

Thanks to both of you!

Luke - I need to go check my results - I am sure I am well below those rates for my pressure (average of between 9 - 10).

Carbonman - I *do* have that chart...but didn't understand "leak rate" as = to "vent flow rate."

But what does "leak rate" actually mean? What is being measured?

The "leak rate" referred to here is the flow that goes out the vent. It's a normal function of the mask. It's actually NOT a "leak", the term "vent flow" on the chart is more accurate. Any "leak" is airflow above that, i.e. uninterntional flow out of the seals.

Leak rate is the intended "designed" leak for the mask at a certain pressure to assure no breathing in co2.
I think vent flow rate is just different terminology for the same thing.
Actually, I spend 66 % of the night at 9 the other 34 % at 10 and if I get anything under let's say 39 for leak its good.



Bill

Ok, wait a minute. I'm still confused.

What am I measuring? If "vent flow rate" = rate to assume no rebreathing of C02, then...what is a "leak rate"? My machine gives me a "leak rate." What is it?

OK, your mask vents CO2 by flushing the mask interior with air during exhale. It all goes out the vent (usually blowing on your sleeping partner's neck... ). The machine sees that as a constant "leak", even tho it's intentional. But it's a "good" leak.

Any unintentional leaks (like the ones that blow constantly in your eyes, or the intermittant "mask farts") are on top of the vent flow. Those are "bad" leaks.

The total "Leak Rate" is both kinds added together.

Unless your machine has you enter the vent rate for the particular mask you use, it's reporting the total and you should only worry about the amount OVER your mask's vent rate. (Sorry, I don't know if Resmeds do the math for you or not.)

OK, just checked my machine. It is giving me leak rates per second. Last night, my rate was 0.24 L/s. For the week, my rate was 0.10 L/s.

How do I convert those to litres per minute? (I know, dumb question, right?) I assume I multiply by 60 (for the 60 seconds in a minute).

So, if I multiply my weeky rate of 0.1 L/s by 60, I get a leak rate of 6. Which is pretty good...even excellent, right?

MoneyGal wrote:OK, just checked my machine. It is giving me leak rates per second. Last night, my rate was 0.24 L/s. For the week, my rate was 0.10 L/s.

How do I convert those to litres per minute? (I know, dumb question, right?) I assume I multiply by 60 (for the 60 seconds in a minute).

So, if I multiply my weeky rate of 0.1 L/s by 60, I get a leak rate of 6. Which is pretty good...even excellent, right?

Yes, you are doing it correctly.

0 is excellent.

6 is certainly good and even last night's 14.4 is manageable. Your machine will compensate the pressure for the leaks up to a point. I'm thinking I read that up to around 20 lpm your machine can maintain your correct pressure. So as long as your leaks aren't bugging the crap out of you or burning your eyes, you're good at 6 lpm,..

Hey, this is all awesome. Nothing is bothering me. I feel like I won the jackpot - I put the mask on, turn on the machine, and go to sleep. About 7.5 hours later I wake up, and get on with my day.

Since you are using the Resmed Elite II, your machine automatically compensates for the flowrate of that Resmed mask; just ensure that the settings reflect the correct mask in setup and you won't have to fumble with the charts and math.

Paul

MoneyGal wrote:OK, just checked my machine. It is giving me leak rates per second. Last night, my rate was 0.24 L/s. For the week, my rate was 0.10 L/s.

How do I convert those to litres per minute? (I know, dumb question, right?) I assume I multiply by 60 (for the 60 seconds in a minute).

So, if I multiply my weeky rate of 0.1 L/s by 60, I get a leak rate of 6. Which is pretty good...even excellent, right?

0.24 L/s is within acceptable range as Resmed consider anything at or under 0.34 L/s to be within acceptable limits; however, there can be spikes in your leak rate during the night which you can only view with ResScan.

Well, last night I mistakenly turned the machine on before the mask was on, so I had 15s or so of "high leak." The weekly rate is probably more indicative of my "normal" leak rate.