"It's going to become more challenging to determine whose device is okay and whose isn't," said Kelly Skyles, a 26-year flight attendant and national safety and security coordinator for the Association of Professional Flight Attendants, the union that represents cabin crews at American Airlines. "My greatest concern is that it's going to put flight attendants at risk for more confrontations."
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Not to mention that passengers will sometimes sneak in a few Words with Friends turns when they think they can get away with it. "You can't be looking at everybody all the time," said Tiffany Hawk, a former flight attendant and the author of "Love Me Anyway," a novel about airline culture. "People are always pretending to turn things off even when they're not."
The FAA's revised guidelines are in line with the recommendations presented to it by a 28-member advisory committee in September.
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The agency has come under increasing pressure in recent years from passengers, lawmakers and the electronic device industry who have argued the devices pose little threat.
Passengers are currently required turn off devices when planes are below 10,000 feet to avoid electronic interference with cockpit equipment during takeoff and landing. There are no confirmed reports of passenger devices interfering with flight navigation devices.
—By Ben Popken, NBC News