A woman was killed yesterday (Dec. 14) in New York City when the elevator she was stepping into suddenly lurched upward with its doors open, crushing her against the shaft wall. It was the second death in as many weeks: A woman died at Cal State Long Beach on Dec. 7 when she was crushed while trying to crawl out of a car stuck between floors.

Elevators being a vehicle of the masses, these tragic and gruesome accidents raise the question: Just how dangerous are they?

As it turns out, they're safer than taking the stairs.

Elevators make 18 billion passenger trips each year in the United States, according to ConsumerWatch.com. (Meanwhile, the entire world population is 7 billion people). The U.S. Bureau of Labor Statistics and the Consumer Product Safety Commission estimates that all those ups and downs result in a yearly average of 27 deaths. Unsurprisingly, those most at risk are the mechanics whose job it is to work on faulty elevators. The Los Angeles Times calculated that the elevator fatality rate is thus 0.00000015 percent per trip overall, and, of course, it's even lower for the general public.

A 2009 report by Occupational Health & Safety attributes the rarity of elevator fatalities to "intricate, redundant, and regulated safety features built into every elevator." Elevators typically have four to eight times as many cables holding them up than they actually need, and they also have automatic braking systems near the top and bottom of the shaft, backed up by electromagnetic brakes. Finally, "at the bottom of the shaft is a heavy-duty shock absorber system designed to save passengers if all else fails," the report stated. [How to Survive an Elevator Free Fall]

Clearly these safety features don't rule out the occasional freak accident, but they do much better at protecting passengers than movies and TV shows would imply.

For comparison, while 27 people die in U.S. elevators annually, an equal number are killed in car accidents in this country every six or seven hours. If you're still wary of taking the elevator, consider this: Approximately 1,600 people die annually from falling down the stairs, according to data from the Center for Disease Control's National Center for Health Statistics.

This story was provided by Life's Little Mysteries, a sister site to LiveScience. Follow us on Twitter @llmysteries, then join us on Facebook. Follow Natalie Wolchover on Twitter @nattyover.