Can you climb Everest without oxygen?
The answer to this question is yes, but not for most people. Everest was first climbed without bottled oxygen on May 8, 1978 by Reinhold Messner and Peter Habeler. Up until that point, scientists thought it would be guaranteed death to go to those heights without supplemental oxygen. And it would be for most of us. The ability to climb to the summit of Mt Everest without bottled oxygen is mostly genetic. Obviously you need to be supremely fit, but you also need to have the genetic ability to do so. Without this, it does not matter how fit you are, you will not make it and you stand a strong change in dying in the process. This is not something you can test for in a doctor’s office; there is no blood test or MRI that will tell you and lineage alone does not guarantee it. The only way to know is to learn by experience.
The best strategy if you want to attempt this is to climb to higher and higher summits over a period of years. Not only will you gain the technical expertise required, but you will also learn how your body responds to the thin air. Similar to muscle memory, your body learns every time you go to altitude and it can make the adjustments slightly easier the next time. However, even this is not a sure-fire way to know. And even if you have never had any altitude issues before, it could crop up at any time without warning notice. Many highly experienced and strong climbers have died from altitude related illness when they had never experienced issues in the past.
Even the Sherpas need bottled oxygen. They are stronger than the average westerner and their bodies have adapted to living at altitude over the centuries, but they are not immune to altitude-related illness. A Sherpa climber will die from altitude almost every year, and this is partially because they work very hard and carry such heavy loads while on the mountain. Above 8,000m almost everyone, including the Sherpas, are wearing an oxygen mask and carrying oxygen in their packs.
The standard system on Everest is Poisk which is a Russian system that combines a lightweight aluminum and Kevlar oxygen bottle, a flow regulator and a mask. This system has not really changed or been improved in decades. There are a few other systems out there and one of the biggest changes in recent years is a new British mask called the “Top Out”. It uses the Poisk bottle and regulator, but adds in a more efficient mask design that delivers a greater percentage of usable oxygen to the lungs.
Most climbers will have five 4-litre oxygen bottles that they will use from Camp 3 and up. Running at full flow, the tank will last about 6 hours. Running at minimum flow, it can last 12-14 hours. Most people will run it at around mid-flow and this will allow them to climb efficiently and to not run out of oxygen.
Using oxygen does not make it feel like you are at sea level, but the general consensus is that it makes it feel like you are about 3000-feet lower in altitude. One of the dangers of using oxygen on Everest and other 8000m peaks is that it allows you to push beyond what your body could do without the oxygen. If your system fails, your regulator freezes or you run out of oxygen, all of which has happened on Everest, you are in big trouble. Instantly, your body acts as if it has been propelled 3000-feet higher and things go bad very quickly. If this happens to you, you will be extremely lucky to survive.
When I was climbing Everest there was only one person (that I am aware of) to summit without the use of supplemental oxygen. I spoke to him at the top of the Hillary Step. I was going down from the summit and he was going up. We had a quick chat and he seemed to be doing well. His lips were a little blue, but most people’s are at that height. He was a very experienced climber and had climbed other 8,000m peaks successfully without oxygen. I continued down and he continued up. When I woke the next morning at Camp 4 and stepped outside my tent, I saw him laying dead and wrapped in a tarp.
Somewhere on the descent he had run into trouble. After reaching the summit his body had started to shut down, as often happens. He had no resources left to combat the rapid deterioration of his body and he collapsed. I was not there so I do not know exactly what happened, but I heard that some Sherpa’s did put him on oxygen, but by that point it was too late and he died of heart failure.
Based on my personal experience, I do not think that I could ever climb Everest without the use of supplemental oxygen and I will never try. Some people feel this is cheating and an unfair and un-pure way to climb. But that is a whole different topic.