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+--- Thread: Why don't mask manufacturers publish Pressure Ratings for their masks? (/Thread-Why-don-t-mask-manufacturers-publish-Pressure-Ratings-for-their-masks)
Why don't mask manufacturers publish Pressure Ratings for their masks? - S. Manz - 08-21-2021
As an engineer I have a technical understanding of pressure support by devices that are designed to handle pressure. CPAP masks are no different.
Each mask is designed to deliver the air flow at specific maximum pressures set by your CPAP device while the mask itself has to form a seal with your face in order to contain this air volume at a specific max pressure , however masks are like all other devices when the "seal" is designed to contain up to a maximum pressure before it "blows". For example your car tires or your BBQ Propane Tank or any other pressure vessel.
All these vessels are required by law to exhibit their maximum pressure support rating...but not CPAP masks.
When you are shopping for a mask, you have absolutely no clue whether or not it will handle your "Prescribed Pressure" so you bring it home to try.
The first night it will keep leaking, so you tighten up the head gear to compress the seal but it leaks again so you keep tightening the darn thing until your face looks like a pancake and just when you manage to contain the pressure, you find that it is absolutely impossible to fall asleep with your new contraption, so you give up.
The truth is that your mask was never "rated" for your prescribed pressure in the first place, but since mask manufacturers are not obliged to publish their pressure ratings, you had no way of knowing.
Good news is that this data can be obtained with some fishing over the internet. So next time you are shopping for a mask, it may be a good idea to research it's pressure rating before you part with your money....and sanity.
Now, don't be shy and tell us about your struggles with mask leaks and how you finally fixed it....or if you ever fixed it at all.
RE: Why don't mask manufacturers publish Pressure Ratings for their masks? - Gideon - 08-21-2021
CPAP masks are designed to be lightly held to the face. Honestly it would take a lot of pressure to blow the seal of a properly fitted mask, far more than your device produces.
The first analytical task is to fully realize what the very low pressures used by CPAPs (20cmw), BiLevels (25-30 cmw), all well under 1 PSI.
Most masks seal because the delivered pressure actually extends a flap llf silicon which forms the seal. Over tightening actually distorts the mask and causes leaks.
The foam masks do not work on this principal and actually require you to distort the foam to confirm to your face. Even wiith these overtighrening will cause a facial distortion and leaks.
RE: Why don't mask manufacturers publish Pressure Ratings for their masks? - greatunclebill - 08-21-2021
CPAP's are actually in the range of 1/3 Psi or less. Try the balloon experiment. put any balloon on the outlet of your cpap. it will not blow it up. if the balloon is big and loose it may fill up the loose space. but will not inflate it. It is very low pressure and high volume like a fan. there's no air pressure created in a fan.
RE: Why don't mask manufacturers publish Pressure Ratings for their masks? - S. Manz - 08-21-2021
There absolutely IS pressure.
10 CMH2O is the equivalent of about 0.15 Psi and CPAPS can go up to 30 CMH2O which is the equivalent of about 0.5 Psi...That is quite a lot of pressure at fairly significant volumes like 10 Liters per minute.
That much pressure requires a very good seal or it will no doubt "leak" (blow)
RE: Why don't mask manufacturers publish Pressure Ratings for their masks? - SarcasticDave94 - 08-22-2021
10 cmH2O = 0.142233 PSI
30 cmH2O = 0.4267 PSI
Adding one more, the machine my RT says I need, Astral 150, Max is 50 cmH2O = 0.711167
My Fisher and Paykel Vitera that works fine on the ASV, will also be able to pair with the Astral. Why? Paying attention to proper fit, strap adjusting, and placement. My best leak rate was Max of 10 while on my typical ASV Auto settings EPAP 8-13 PS 3-15 IPAP 11-28. 10 on the leaks was a repeatable rate, I didn't sacrifice comfort, nor did I take months to refine it further. Could I get it lower? Probably but I didn't.
Why aren't there pressure statistics on CPAP masks? I guess FDA and the manufacturers didn't consider it.