Tuesday, November 24, 2009

High Altitude Oxygen

We are always hearing about 8000 meter mountains and the use of oxygen. Should it be used of should it be left behind?

This blog entry has absolutely nothing to do with this common debate about oxygen in the mountains, but instead explains what

There are really two systems being employed in the high mountains. They are the constant flow system and the demand system.

The constant flow system delivers oxygen on a constant basis through a face mask worn by the climber. A flow rate is set and the oxygen keeps coming at that rate until you are out. This system is also often referred to as the Poisk system.

The second kind of oxygen flow system is the demand system. In this system, the climber wears a nose pipe that only provides oxygen when you inhale. The value of this system is that it's running half the time that a constant system is running. As a result, you have to carry half of the oxygen cylinders that you might carry otherwise.

The demand system has been used for nearly twenty years, but it has some problems. These include frozen tubes and release of oxygen when not in demand.

There is a third alternative which is a heavier and less realistic system and that is the closed circuit oxygen system. Most systems are a combination of the ambient oxygen in the air and supplemental oxygen from a bottle. In a closed circuit system, all of the oxygen is coming from a bottle, which could theoretically reduce the altitude feeling to sea level.

As the weight of all that oxygen is unrealistic, there has never been a valid test of a true closed system.

In the following video, we see the different parts of a normal constant flow system.

The first ascent of Everest in 1953 required quite a bit more in weight and old school technology. The following video shows a diagram of the original oxygen system and quickly describes how it worked.

The oxygen debate is one that will always rage, but that has nothing to do with the actual oxygen systems. If you choose to use oxygen in the high mountains, research each of the different systems, including brands and models available. Your summit and your life depend on making the right choice.

--Jason D. Martin

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