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Acceptable leak # - Printable Version

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Acceptable leak # - pennidragon - 01-04-2016

Does anyone know what is an acceptable leak with the PR DreamStation machine. I'm looking at my data and with the Dreamwear my leak is usually around 19-22 Total Leak (LPM) I assume that's leaks per minute??. With the Amara View my leak avg in 30s sometimes in the 40s during the night.


RE: Acceptable leak # - justMongo - 01-04-2016

I don't know what's acceptable for the Dreamstation.
However, I'd like to say that LPM is Liters Per Minute for the leak rate.

I do believe that all PR machines report total leak which includes the intentional leak created by the mask vent.
The Amara View, being a FFM, likely has a greater vent rate to flush the mask of exhaled air -- that could explain the higher Total Leak Rate when using the Amara View.


RE: Acceptable leak # - Sleeprider - 01-04-2016

Your current leak rate is essentially zero other than the designed intentional venting. Acceptable leaks will increase with increasing pressure and volume of mask. So acceptable leaks are less with pillows, then increase with nasal masks, and full face masks. The machine will probably record a large leak if you go above 50 or 60 lpm for any period of time.


RE: Acceptable leak # - pennidragon - 01-04-2016

Thanks for the info! Just wanted to make sure my leaks were acceptable.


RE: Acceptable leak # - esrepairman - 01-04-2016

19-22 sounds reasonable. Manufacturers used to provide spec. sheets with each mask, literally graphing out expected leakage through the exhalation vents for each mask. Not sure why they discontinued this practice.


RE: Acceptable leak # - Canuck 2 - 01-04-2016

Resmed believes leaks below 24 litres are not really excessive, the lower the better no doubt.
Rescan 5.5 software has a red dotted line at 24 litres if that is of any help.


RE: Acceptable leak # - justMongo - 01-04-2016

(01-04-2016, 03:25 PM)Canuck 2 Wrote: Resmed believes leaks below 24 litres are not really excessive, the lower the better no doubt.
Rescan 5.5 software has a red dotted line at 24 litres if that is of any help.

But comparing ResMed's definition of leak to Phillips-Respironics' is apples to oranges, ResMed says 24 LPM for unintentional leak. PR reports the combined unintentional leak with the vent rate.

My mask vent rate approaches 50 LPM at upper pressure limits; plus you have the positive flow on inhale. Blower units would seem to need to comply with flow rates higher than 75 LPM while maintaining pressure. The motor control must be very sophisticated.


RE: Acceptable leak # - yuccadave - 04-13-2016

My assumption is that LPM means Liters Per Minute of airflow.

There is a web site that has the Philips Respironics Intentional Leak Rates sheet. Search for "Intentional leak rates for masks and exhalation ports". Include the quotation marks.


RE: Acceptable leak # - Mosquitobait - 04-13-2016

(01-04-2016, 09:22 AM)justMongo Wrote: I do believe that all PR machines report total leak which includes the intentional leak created by the mask vent.

Ahh.. that would explain why the numbers for a high leak are different with PR machines than Resmed machines. This has confused me for awhile (bro has a PR bipap).




RE: Acceptable leak # - palerider - 04-13-2016

respironics reports *total* leak.

resmed calculates, and reports *excess* leak.