"American Dies at Mount Everest, Bringing Death Toll to 11 Amid Overcrowding Concerns "

"Even when using bottled oxygen, supplemental oxygen, there's only a very few number of hours that we can actually survive up there before our bodies start to shut down. So that means if you get caught in a traffic jam above 26,000 feet ... the consequences can be really severe," he added."

https://ktla.com/2019/05/27/american-dies-at-mount-everest-bringing-death-toll-to-11-amid-overcrowding-concerns/