(NEW YORK) -- More than 300 security guards at New York's John F. Kennedy Airport are threatening to go on strike just as an estimated 42 million people will be flying on airplanes for the holidays.
One group of workers on Thursday approved a vote to strike on Dec. 20 if their company, Air Serve, does not agree to their demands. A second group of workers employed by Global Elite Group will hold a similar vote on Friday.
These employees at the nation's sixth-largest airport are non-union workers hired by outside, private contractors. The workers want better training, functional radios and proper uniforms for cold and rainy weather.
It's unclear what impact a strike would have on JFK at the height of the holiday travel season as an estimated 42 million passengers will fly nationwide between Monday, Dec. 17 and Jan. 6.
Airline tickets are in high demand right now, which means more expensive ticket prices, according to a report released Thursday by Airlines for America. Planes are flying at 85 to 90 percent capacity for the 21-day holiday travel period.
The time for holiday airfare bargains is over. Non-stop ticket prices for Christmas week are nearly double what they were at the beginning of the month, and rising by the day.
"The time to book was weeks ago, but if you haven't booked yet you have to pull the trigger right now," ABC News' travel and lifestyle editor Genevieve Shaw Brown said. "Prices are going up not every day, but every single hour you wait."
The average domestic air fare is now $414, according to Travelocity, 9 percent more expensive than last year's holiday season. The most expensive days to fly -- up to $500 or more a ticket -- are Dec. 21 and 22, and on the return, Dec. 30 and 31, and New Years Day.
The cheaper days to fly? Christmas Day, and the three days after. Flying on those days can save as much as $330.
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