The Death Zone is located at an altitude higher than 8,000 m (26,000ft) on Mount Everest.
Here the temperatures are always in a very low level which can result in frostbiting any part of the body exposed to the air. The snow in certain areas is well frozen; any slipping and falling may cause injury or death.
What is worse, the winds on the Death Zone are also a potential treat to climbers to reach the summit. Climbers seeking to get to the summit usually spend a lot of time in the Death Zone. They are facing great challenges to survival.
The threats are not just the temperature, the frozen snow and the winds, but also the low atmospheric pressure of the high mountain. At the top of Mount Everest, the atmospheric pressure is just about a third of the sea level pressure or 0.333 standard atmospheres (337 mbar), which meanings that there is only a third as much oxygen as the sea level oxygen to breathe.
The death zone’s debilitating effects are so great that most climbers need more than 12 hours to trek a distance of 1.72 km from the South Col to the top. The acclimatization of the altitude of the Death Zone takes climbers 40-60 days which is very long. A people living at sea-level exposed to the atmospheric condition of the death zone without the acclimatization, he may lose conscious for 2-3 min.
The Caudwell Xtreme Everest made a study of oxygen levels in human blood at extreme altitude in 2007. There were more than 200 volunteers to climb to Mount Everest Base Camp. The result of the study shows that even at the base camp, the atmospheres pressure of low oxygen had direct effect on the saturation levels of blood oxygen. The blood oxygen saturation at the sea level is about 98%-99%; while it is between 85% and 87% at the base camp. At the summit, the blood oxygen saturation is very low. It has a side effect to increase the breathing rate, which is 80-90 breath per min normally but add 20-30 breaths more on the summit. Just for attempting to breathe can result in the exhaustion of the body.
At the death zone, when lack of oxygen and under the extreme cold temperature, climbers will fell exhausting, hazard. It is very important to avoid yourself from any injures, as the rescue by helicopter here is not practical and to carry an injured person off the mount is very dangerous. Up to now, there are about 150 bodies haven’t been recovered. So, it is not impossible to find a dead body lying near the routes you climbing.
Death has never been a new phenomenon at the peak of the so-called "roof of the world", especially in the death zone.
Tsewang Paljor, well-known with a nickname "green boots", was once a border policeman in India and died in the death zone in 1996.
For nearly two decades, his body lay quietly on the north slope, not far from the summit of mount Everest, and has become a terrible landmark for those trying to conquer the world's highest mountain.
In 1998, Francys Distefano Arsentiev, known as the sleeping beauty, died on mount Everest. She was the first American woman to climb Everest without an oxygen bottle.
On May 22, 1998, Francis achieved her wish to reach the summit of mount Everest. However, she was forced to spend the night in the "dead zone" due to lack of oxygen. In the early hours of the next morning, the climbers Ian Woodall and Cathy O'Dowd spent more than an hour with her in the cold, then left for self-protection. Francis died of frostbite and exhaustion.
On mount Everest, even the best prepared climbers, may also suffer from a sudden heart attack, stroke, irregular heartbeat, acute pulmonary edema and cerebral edema caused by asthma and hypoxia at any time.
Dr. Monica Perez, a Spanish doctor working at Everest base camp, once said, at the height of more than 7,000 meters above sea level is more dangerous. Frostbite, hypothermia, nerve damage and even death are common.
Beijing, Xian, Lhasa, Shigatse, Tingri, Mt. Everest, Shanghai