What benefit is a hepa filter ? - who uses them ?

dsm · Post by **dsm** » Sun Nov 27, 2005 4:34 am

While tracking down new parts for my RemStar, I came across the hepa bacterial filter.

I was wondering what these are and who uses them.

Anyone able to elucidate

Thanks

DSM

groggybob · Post by **groggybob** » Sun Nov 27, 2005 6:32 am

DSM, try the following site, lots of information. I used to deal with HEPA filters when I worked on vacuum cleaners but have no knowledge of them for CPAP.

http://asthma.about.com/od/asthmabuyers ... uyhepa.htm

Bob

meister · Post by **meister** » Mon Nov 28, 2005 2:32 pm

I use one! It helps insure that the air reaching your lungs is
as free of pollen and dust mites, etc. as it can be. However,
I was thinking that the filter reduced the pressure coming
through the pipe, so I increased the pressure on my machine
to compensate for any loss due to the filter. Now I will
examine the filter after a couple of months and see if it gets
dirty. I have been seeing lower AHI values since installing
the filter. Could just be coincidence, though.

groggybob · Post by **groggybob** » Mon Nov 28, 2005 4:27 pm

Meister, In my current profession as a HVAC technician we have found that the so called "high efficiency" filters and HEPA filters designed for furnaces and air conditioners actually cut down on the air flow and thus the efficiency of the given unit. It stands to reason that this would be the same for CPAP machines. Somebody more knowledgable in their design may be able to shed some light on that.

Bob

nodding off · Post by **nodding off** » Mon Nov 28, 2005 6:33 pm

Hi Meister,
You can buy a manometer for cheap on CPAP.com. If you are going to adjust your machine (and we all tinker with them), and it's a CPAP, I would recommend getting one and using it. Then you will know exactly how much pressure you are being delivered. It doesn't really matter if you feel good and your numbers are good unless you are switching machines and want the same pressure settings, and matters even less on an APAP.

smyles · Post by **smyles** » Sat Dec 03, 2005 11:15 pm

DEISM,

A few explanations before I comment on your post. I'm an Industrial Hygienist.

The term HEPA stands for High Efficiency Particulate Air. True "HEPA" filters are designed to capture respirable "dust" (particulate) greater than 5 micron in size. This is about the size of dust mite poop! The stuff we're allergic to! Dust particles smaller than 5 micron can pass through the filter, however, their likely to be passed through the lungs and back out during breathing without any contact. Please note that there are standards for true "HEPA" filters related to respiratory protection devices. They are designated by the code P100 and are typically surrounded by a support structure that is colored pink.

I have not come across any manufacturer, Respironics included, that provides true HEPA filters for their machines. Rather, the disposable "Ultra-Fine" filters sold by Respironics are sufficient in removing the dust/irritants your concerned about. I recommend changing them out monthly. If you compare the color of a used one to a new one, you'll be amazed how efficient they work!

Please hesitate when purchasing 3rd party HEPA filters. I agree with the HVAC technician who also responded to your post. These filters may alter the pressure intake/discharge of your machine and may alter the capability of your CPAP to deliver the proper pressure setting during your therapy. Good luck!

MissAmethyst2U · Post by **MissAmethyst2U** » Sat Dec 03, 2005 11:51 pm

I am soooooooo glad to see this post. I was just given the HEPA bacterial filter at my appt friday by the sleep tech there and they are supposed to order me more to always have to replace. One of the first things she said to be was it wont mess up your pressure or anything but first night with it I felt as though I was suffocating at time as it felt to be a lower pressure than 9 I was getting. I think I will call Monday and see if I can take my machine to them to up my pressure to 9.5 or 10 prob 10 just so I feel better I dont see where that would hurt right if my pressure is 9 now and my apneas are between 0.1 and 0.9 an hr with a pressure of 9 but that darn filter and I actually think it does help with my severe allergies and asthma I think it needs to go to 10 cause I have been more tired this weekend during the day since using the filter...

dsm · Post by **dsm** » Sun Dec 04, 2005 3:51 am

smyles,

Many thanks for your post. To us mere mortals such commentary is valuable.

I am about to buy some filters and your input is influential and appreciated.

Cheers DSM

Goofproof · Post by **Goofproof** » Mon Dec 05, 2005 4:24 pm

As a mechanic, I would think where the filter was installed. If it was installed on the intake, the machine is made to control output pressure, so the pressure should be the same.

If the filter is installed one the output (hose side) then the machine has already set the pressure and flow, anything after that could lower the pressure.

groggybob · Post by **groggybob** » Mon Dec 05, 2005 5:09 pm

I have to disagree with you Goofproof. A heating and air conditioning unit is essentially a giant CPAP machine as far as air flow is concerned. One of the most common complaints we get is that the unit is not outputting sufficient heat/cooling. The common cause of this complaint is clogged filters or the use of filters with smaller openings than recommended by the manufacturer. i.e. HEPA and "high efficiency" filters. The cubic feet per minute of airflow available to the blower falls below the blowers output c.f.m., thus resulting in lower air flow. Just for kicks, pull the filter out of your CPAP and place your hand over the air intake while the machine is running and you have your mask on. Guarantee you will notice a difference.

Would be great if someone on cpaptalk with a manometer and a few different filters could do some testing and settle this for all of us. Hint, Hint

My .02,
Bob

Goofproof · Post by **Goofproof** » Tue Dec 06, 2005 12:57 pm

[quote="groggybob"]I have to disagree with you Goofproof. A heating and air conditioning unit is essentially a giant CPAP machine as far as air flow is concerned. One of the most common complaints we get is that the unit is not outputting sufficient heat/cooling. The common cause of this complaint is clogged filters or the use of filters with smaller openings than recommended by the manufacturer. i.e. HEPA and "high efficiency" filters. The cubic feet per minute of airflow available to the blower falls below the blowers output c.f.m., thus resulting in lower air flow. Just for kicks, pull the filter out of your CPAP and place your hand over the air intake while the machine is running and you have your mask on. Guarantee you will notice a difference.

Would be great if someone on cpaptalk with a manometer and a few different filters could do some testing and settle this for all of us. Hint, Hint

My .02,
Bob

groggybob · Post by **groggybob** » Tue Dec 06, 2005 8:26 pm

"we could just tape the output of a shop vac to our mask" Oh no, don't let mikemoran see this.

Heating and AC systems are indeed designed to run at a set flow and pressure for optimum efficiency, otherwise they are just wasting energy and creating hot and/or cold spots throughout the building.

I look forward to seeing the results of your testing, until then I'll stick with the filters designed for my machine.

What benefit is a hepa filter ? - who uses them ?

What benefit is a hepa filter ? - who uses them ?

Hepa filter

HEPA Filter's

Mask

Mask