British TV presenter Ben Fogle was suffocating. "It felt like losing my scuba tanks under water and I only had one gulp of breath," he told the Sunday Times last year of the moment his oxygen supply cylinders exploded near Mount Everest's summit. Though Fogle's expedition leader and a Sherpa ultimately saved him, allowing him the reach the summit and descend safely, others may not have been so lucky. Per the New York Times, Everest climbers have described numerous equipment problems over the last 20 years, many tied to oxygen cylinders and the regulators which sit atop, controlling the flow of air. A rep for Russia-based Poisk, which supplied more than 90% of the cylinders used in Nepal during that period, argues guides' cost-cutting efforts are to blame. He says guides bypass Poisk to refill cylinders, even after they've expired.
"It's a serious issue," says a tourism official in Nepal, where the government banned cylinders older than 10 years last month. The official adds that army personnel might be sent to base camp to keep an eye on climbers. Yet some argue that concerns voiced up to a decade ago went ignored. In his own tests, British engineer Ted Atkins found 10% of used Poisk cylinders leaked through their valves; others leaked through the body, which expands each time pressure is added, per the Times. As oxygen deprivation affects physical and mental performance, per CNN, it's difficult to know how many might have died as a result of such issues. A 2005 manslaughter case against Poisk, related to the 1999 death of a young Everest climber, was dismissed on lack of evidence. On one expedition, nine regulators failed within an hour. Maker Summit Oxygen later issued a recall. (Read more Mount Everest stories.)