Hey Trooper,

Good on you for using oxygen therapy to abort your CH...  You've made an excellent choice of abortives.

Humidifiers/bubblers don't work very well at a flow rate of 15 liters/minute and higher for a couple reasons... and you just found one of them.   

As the oxygen expands from cylinder pressure to atmospheric pressure it cools very rapidly...  so fast it freezes as you've already seen.  This is called Adiabatic cooling.

The other reason is flow rates of 15 liters/minute and higher flow through the humidifier so fast they cause an atomized water mist to form.  This has a couple negative effects.  The first is you inhale too much atomized water instead of humidified oxygen.  This can lead to a mechanical form of pneumonia.  The second is the atomized water enters the reservoir bag.  After a few hours of this, bacteria and mold will start growing in the reservoir bag and that can have an impact on your health. 

If you insist on using a humidifier, wash the reservoir bag every few days or when it feels slimy inside and hang it upside down to drain and dry.  I used a few drops of J&J baby shampoo and water to wash with.

A little moisture in the reservoir bag is ok after washing and drying as the oxygen is so dry it will evaporate most if not all the remaining moisture.

It's easy to tell when moisture has entered the reservoir bag. Pinch the bag between your thumb and forefinger and try to slide them back and forth.  If there's any moisture inside it will feel slimy and the inner surfaces of the reservoir bag will slide back and forth easily.

I've breathed 100% oxygen for years at flow rates well above 15 liters/minute and never used a humidifier.  If my mouth gets dry, I take a sip of ice water.

Hope this helps.

Take care,

V/R, Batch

Trooper,

Other than sticking with a humidifier with a flow rate of 15 liters/minute, you've done nothing wrong.  I use M-size medical oxygen cylinders, they're about the same size as the large welder's O2 cylinders, and my regulator is always covered with condensation when I use it... and I use a much higher flow rate than most folks so the adiabatic cooling is much more pronounced.

We all need higher oxygen flow rates above 15 liters/minute if we really want rapid relief from the pain when it rockets above a Kip-5.  The simple fact is flow rates this high and humidifiers don't mix...  and using higher flow rates is even more effective.

In short, by-pass your humidifier and you'll be just as happy with your abort times without the additional problems.

If you want a real treat, get a regulator capable of 25 liters/minute or better yet one that's capable of 0-60 liters/minute.  I know that sounds like a lot but climb a couple flights of stairs at a rapid pace and your effective lung ventilation rate will be at least 55 to 60 liters/minute of room air.  Shoot me a PM and I'll send the ordering info.

Take care and keep it up...  You're doing great!!!

V/R, Batch