Cheruiyot Kirui death: Why climbing Mount Everest is a dangerous expedition

The death of Kenyan climber Cheruiyot Kirui during his pursuit to summit Mount Everest has sparked discussion on how precarious such an expedition is.

This is especially so given that Kirui, a banker with the local lender KCB, wanted to reach the world’s highest mountain summit (8,848.86 meters above sea level) without supplementary oxygen.

Kirui went missing with his guide, a Nepali climber identified as Nawang Sherpa, on Wednesday, at Bishop Rock, located at an altitude of 8,000 metres.

The Kenyan’s body was found a few metres below the Everest summit point, as announced on Thursday morning by the Nepali mountaineering news website Everest Today.

For perspective, Kenya’s highest mountain, Mount Kenya stands at 5,199 metres above sea level, while the summit of Kilimanjaro, Africa’s tallest mountain is at 5,895 metres high.

Everest has two base camps; the South Base Camp is in Nepal at an altitude of 5,364 metres and the North Base Camp in Tibet at 5,150 metres.

As such, Everest’s lowest camp is just 49 metres short of the height of Kenya’s highest point.

Most climbing of Everest and the Himalayas is done in April and May when weather conditions are most favourable. It is a tedious process which requires months, sometimes years, of training and conditioning.

Everest climbers have to go through an acclimatisation process to adjust their lungs to the thinning oxygen levels once they arrive on the mountain.

According to CNN Travel, this involves travelling upward to one of the four designated camps on the mountain and spending one to four days there before travelling back down.

Climbers repeat this routine at least two times for their bodies to adapt to declining oxygen levels and increase their chances of survival and summiting.

There have been 11,996 total Everest summits from 1922 to 2023, according to the Himalayan Database, which compiles records of all expeditions in the Himalayas.

More than 327 people are known to have died on the mountain.

In 2023 alone, 12 climbers were confirmed to have died on the mountain, with an additional five unaccounted for.

The database shows that last year saw 655 total summits.

At higher altitudes, Everest is nearly incapable of sustaining human life and most mountaineers use supplementary oxygen past 7,000 metres.

CNN reports that the lack of oxygen poses one of the greatest threats to climbers who attempt to summit, with levels dropping to less than 40 per cent when they reach the so-called 'death zone'.

This is the area past around 8,000 metres, which Kirui alluded to in an April interview when asked about why he did not want to use supplemental oxygen for his expedition.

He said climbing Everest with supplemental oxygen would be quite easy, and that was not what he wanted.

“The challenge for me would be without supplemental oxygen; otherwise, I wouldn't feel like I've achieved much. So, I want to see how my body can cope in such altitude,” the banker said then.

In this ‘death zone’, the air is extremely thin, temperatures are below 0°C and the high winds are powerful enough to blow a person off the mountain.

Climbers face high-altitude cerebral edema (HACE), where one’s brain is starved of oxygen.

This results in brain swelling, causing drowsiness, and trouble speaking and thinking. One might also experience blurred vision and episodes of delusion.

The first Everest summit without supplemental oxygen was in 1978 by Italian Reinhold Messner and Austrian Peter Habeler.

They demystified experts’ thought that the human body could not cope with such low oxygen levels.

According to a 2016 report by National Geographic, less than 200 people were known to have summited Everest without oxygen by then.

Statistics from the Himalayan Database show that as of January 2024, climbing Everest from the Nepal side, which is the most popular, has a death toll of 217 while the Tibet side has recorded 110 deaths since 1953.

Sixty per cent of the deaths from the Nepal side involved climbers without supplemental oxygen (130 climbers) while on the Tibet side, 48 of those not using supplemental oxygen died, representing 44 per cent of the total deaths.