Wanted - Lab Rats...

HoseCrusher wrote:Chunkyfrog, That is correct. But while the salt is left in the water for the most part, it seems that salt ions can escape and it may be the salt ions that help with the nasal irritation.

I know that many people feel much better when visiting the salt water beaches. I don't think they are breathing salt particles as much as salt ions.

Nope. The "salt ions" can't escape in the evaporated water. It's the water that evaporates in the humidifier and the salt ion remain in solution in the water that's left in the tank. Technically, if you add your "salted water" to the tank, and then use the humidfier without ever emptying or flushing it (simply adding unsalted distilled water each night), you will start each night with the same concentration of salt that you had in the salted water that you started with . Those salt ions "ain't goin' nowhere".

I suspect that peoples sinuses clear out when they are near the seashore because:
1) the air at the seashore is a little more humid than their home, and
2) the air at the seashore is cleaner than their home, with fewer pollutants, dust, and allergens, and
3) odours are power stimulants to peoples memory centers. The salt air at the seashore probably is allowing them to connect with pleasant emotional experiences and memories, giving a powerful placebo effect of well-being.

4) bikinis

Hose Head, In a perfect theoretical world you would be correct.

Have you ever noticed how many times the actual world behaves a little different that what is proposed in theory?

In my test I put salt water into my humidifier. I collected condensate from the end of the hose in a glass. When I put distilled water into the glass and measured it with the PWT I had a reading of 1.2. When I measure the condensate from the humidifier in the glass I have a reading of 168.2.

In a theoretical world, the reading would not change, but in the actual world, something is getting through.

For the record, when I tasted the condensate, it did not taste salty, so the actual concentration is very small.

My water distiller does a much better job of purifying water than my xPAP humidifier does.

I invite you to do this same test yourself and see what you get. Something is getting through and it very well could be the salt ions.

Did I miss the meaning of "PWT" ?

HoseCrusher wrote:Hose Head, In a perfect theoretical world you would be correct.

Have you ever noticed how many times the actual world behaves a little different that what is proposed in theory?

In my test I put salt water into my humidifier. I collected condensate from the end of the hose in a glass. When I put distilled water into the glass and measured it with the PWT I had a reading of 1.2. When I measure the condensate from the humidifier in the glass I have a reading of 168.2.

In a theoretical world, the reading would not change, but in the actual world, something is getting through.

For the record, when I tasted the condensate, it did not taste salty, so the actual concentration is very small.

Any real world behavior that matches theory is purely coincidental!

Do you have any feel for how much more air was passing through the hose in your test than will when you have your mask on? I suspect the air velocity in the hose during your test was great enough to carry minute water droplets all the way from tank to glass. It's possible, I suppose, for water droplets to get carried from the tank to your mask when you're using the CPAP. The only question is if enough droplets carrying enough salt make will it all the way without condensing inside the hose. If you can get that delicate balance to work in your favor you very well may be onto something.

Oh, what is PWT? I'm too lazy at the moment to go search for the answer!

Well Rooster, I recommend that you put a Bikini on and see if your sinuses clear and report back to us with pictures of course viewtopic/t58490/posting.php?mode=reply ... 58490#:lol:

PWT = Pure Water Tester. Mine is from Hanna. It measures in micro siemens. If you know the conductivity of the particular salt you are interested in, you can develop an equation to convert micro siemens to parts per million. This is how PPM meters work.

I brew my own distilled water and use the PWT to determine how well I am doing. While my applications are not "critical," I can make water that is purer than the distilled water I can purchase, but I have to double distill it to do so.

HoseCrusher wrote:Hose Head, In a perfect theoretical world you would be correct.

Have you ever noticed how many times the actual world behaves a little different that what is proposed in theory?

In my test I put salt water into my humidifier. I collected condensate from the end of the hose in a glass. When I put distilled water into the glass and measured it with the PWT I had a reading of 1.2. When I measure the condensate from the humidifier in the glass I have a reading of 168.2.

In a theoretical world, the reading would not change, but in the actual world, something is getting through.

For the record, when I tasted the condensate, it did not taste salty, so the actual concentration is very small.

My water distiller does a much better job of purifying water than my xPAP humidifier does.

I invite you to do this same test yourself and see what you get. Something is getting through and it very well could be the salt ions.

The salt certainly cannot be moving in the evaporated water. That's not possible. If it were possible, no distillation process would work. It's much more likely that salt may be moving in solution in liquid water droplets that are entrained in what I suspect is an unusually high air flow in your experiment. If this is the case, then your experiment proves nothing about how much salt might be passing through the hose to your sinuses.

A couple things you could do to test this :
1) wash your hose thoroughly, then run distilled water through it, catch the water and test with your PWT meter. Record the value. Then repeat your experiment by collecting the condensate from the humidifier. Afterwards, rinse the hose again with distilled water and collect and test it again. If the wash water of your hose is higher conductivity, at least you've narrowed down the source of the conductivity (i.e. it's coming from the humidifier as you've claimed.)

2) run the above experiment again, but this time restrict the airflow to match the leak rate specified for a mask e.g. about 30 L per minute. This will duplicate conditions that one would experience when using the cpap. Report on the change in conductivity, including that of the wash water used to clean the hose after the experiment.

Incidently, if your experiment shows that salt can move from the humidifier to the mask with an airflow of 30 L/min or so, then we all should be much more concerned about microbes and fungi following the same path! There have been a lot of discussion on this board about the need for sanitizing the humidifier and use of sterile water. Your experiment can add useful data to the discussion!

The results, empirical and measured, are interesting enough that this definitely deserves further study.

Anyone who has access to an ohmmeter can repeat this experiment. Conductivity is the reciprocal of resistance, or Seimens = 1/Ohms and vice versa. Thus, a very high resistance equals a very low conductivity.

I am thinking that the water in a humidifier is being agitated by the air passing over it, and it is not boiling. Therefore, the mechanical disturbance of the water is enough to cause some nebulization to occur. Apparently, the needed amount of salt in the air stream to have an effect is very small.

One thing I would be concerned about is salt getting back into the machine. Most modern machines have their humidifier as essentially part of the machine. Normally, salt dust should not make it back into the machine. But if you cough or do something else that causes the air stream to pass back into the machine, any salt in that air could be deposited on the flow and/or pressure sensors in the machine, where I am sure they will not help matters.

So here is what I would do: Get yourself an external humidifier, like an HC-150. Hook it to the machine using a readily available 18 inch (or longer) hose segment. It might even be possible to rig a check valve to protect the machine. Respironics sells a check valve assembly for their Remstar heated humidifier. Because it is something that is supposed to be periodically replaced, it is readily available as a spare. The size of this valve assembly is such that it would likely fit on the input of an HC-150.

I would be concerned about possible salt corrosion if your humidifier has any parts that are any metal but stainless steel. In any case, this will make more work for cleaning the humidifier.

The only real health concern I have is will the small concentration of salt in the breathing air stream have any effect on the lungs or any other part of the respiratory system?

timbalionguy wrote:Therefore, the mechanical disturbance of the water is enough to cause some nebulization to occur.

I agree completely. The phenomenon is not "evaporation" but "aerosolization" which (in re: "ocean air") provides for the entry of "billions of tons" of sea salt into the atmosphere.

http://www.rsmas.miami.edu/divs/mac/fac ... D03401.pdf

There are some very interesting comments here... Thank you all for helping me explore this.

I wonder if there is a way to determine the minimum air flow needed to nebulize the water in the humidifier. In distillation the vapor pressure is what determines the air flow. This is different than having a blower forcing air over a body of water.

I clean my hose and mask daily. This involves a quick "swish" in a bucket of water that has a drop or two of Palmolive dish washing soap in it. I then rinse with tap water, and finish by pouring about 1/4 cup of distilled water through the hose and mask. In the past I have measured this water and it comes in at around 10 on the PWT.

After running the test I decided that I would simply do the rinse with distilled water. I happened to test that water and it came in at about 273.4. I say "about" because the PWT meter tops out at 200 and I had to pour about half the amount out and fill it back up using distilled water to dilute the concentration down to where I could measure it. After seeing this, I did a second rinse with distilled water and ended up with 10.3. Pretty much back to normal.

This tells me that some of the salt vapor was left on the hose wall after my test.

The idea to run the test again at reduced air flow has me thinking that I could do this by going to the other extreme. I use the FX mask. If I plug the pillows, the only air that would be flowing would be through the escape vent. This should be a minimal air flow. I will clean everything and set up for this test and see what happens.

I noticed during my last test that I could see movement in the water in the tank. I will have to check to see if I notice that during the reduced air flow run.

Another variable comes to mind. I fill my tank about half full. I wonder if the amount of water in the tank has any effect on the nebulizing effect...

And yes, from this very crude test it may be possible to nebulize pathogens from a contaminated water tank into your lungs. While I would consider this a remote threat, it appears it could be a possibility. If someone has a compromised immune system, and they use a humidifier, they may want to pay more attention to cleaning the "wet side" of the xPAP device.

NotMuffy wrote:

timbalionguy wrote:Therefore, the mechanical disturbance of the water is enough to cause some nebulization to occur.

I agree completely. The phenomenon is not "evaporation" but "aerosolization" which (in re: "ocean air") provides for the entry of "billions of tons" of sea salt into the atmosphere.

http://www.rsmas.miami.edu/divs/mac/fac ... D03401.pdf

some of us live where there is plenty of salt already in our air - it corrodes much and is a "year long" exposure on our cars not just in the winter when people salt the roads

Another issue that comes to mind: If sodium chloride can ionize at the low temperatures in a heated humidifier,
would it not then be possible for aluminum from the cheapie tank that came with my S9?
I'm not really happy about breathing aluminum ions . . .

HoseCrusher wrote: I wonder if there is a way to determine the minimum air flow needed to nebulize the water in the humidifier.

Ummm, you don't nebulize the water in your xPAP. It evaporates, with the rate dependent on such things as your air pressure and the setting on your humidifier.

I used to work in an asthma research clinic and dealt with nebulizers that are used to administer medications to folks who are having trouble breathing. An xPAP is nothing like one of those.

Chunkyfrog, my humidifier has a stainless steel base. The heater is aluminum, but the water doesn't come into contact with the heater.

Howkim, you may think you don't nebulize the water in your humidifier, but the testing on this may indicate otherwise.

By the way, I believe the term nebulize refers to converting a liquid to a fine spray. While not the same as the traditional medical nebulizer, the end effect is similar.