You're standing on the 34th floor of a skyscraper in a major city when an emergency occurs. Maybe it's an earthquake if you're in San Francisco or Tokyo, it could be a fire if you're in Chicago or Los Angeles, perhaps it's a terrorist attack if you're in New York or London. You're not sure, but it's clear that the first thing you need to is get the hell out.
The only option? The stairs. It makes sense to you, and it also happens to be what the fire warden told you to do during his umpteenth drill earlier this year.
Soon, that advice may not be foolproof. Matt Van Dusen writes at Txchnologist that new "occupant evacuation elevators" -- yes, emergency elevators -- have worked their way into the 2012 version of the International Building Code.
The result: a massive exception to the lessons many have been taught since they were children.
For more than two decades, fire engineers have been debating this bedrock of building occupant safety and have concluded that elevators can be designed and used for emergency evacuations. This is true not just for ultra-tall skyscrapers like the 2,700-foot Burj Khalifa and the 1,671-foot Taipei 101 tower, which both have emergency elevators, but for buildings over 420 feet.
The advantage of an emergency elevator should be obvious: it's much faster than evacuation on foot, so fast in fact that it could clear a supertall building in less than an hour.
For now, such elevators are complex to design and install, and reserved for only the boldest of buildings. But their very existence could have you questioning yourself in a moment of crisis.