Transcript for At least 5 climbers have died in the past week climbing Mt. Everest
to mt. Everest where three new deaths are raising concerns about dangerous gridlock at the top of the world's tallest mountain. At least five climbers have died over a 48-hour period including an American. ABC's Julia Macfarlane has more. Reporter: A traffic jam on mt. Everest has now claimed the lives of five climbers in the last three days including Utah climbing enthusiast don cash when he suddenly fainted from high altitude sickness Wednesday. Experts say an area known as the death zone where oxygen measures at one-third the normal level could be to blame. Climbers like mountain guide Garrett Madison wasting hours of precious oxygen as they wait for 150-mile-per-hour winds to ease. There are probably a couple of hundred climbers up there and it creates some congestion on the route. Reporter: Experts tell ABC news supplemental oxygen is an absolute necessity when climbs this part that soars over 26,000 feet. Experts say overcrowding at the top of the world is making the mountain more dangerous than ever. This year it's been a particularly windy season and so once the weather window developed and we had a chance to go for the summit, everybody went pretty much the same time. Reporter: According to Nepal's department of tourism, a record-breaking of 381 permits were issued this year and with each climber requiring a sherpa to climb them lines reached epic proportions. Instead of taking 12 hours to do the round trip they were taking 20 and when you take that long and run out of supplemental ox begin, it's a deadly combination. Reporter: The Nepalese government's only requirement for a permit is $11,000. Whit. We do want to come back. The holiday weekend turning into a washout in the nation's Giraldo hit by a dozen
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