State officials say it's not easy to prevent people from falling and injuring themselves on escalators, even when they're working properly.
Nobody knows that better than the people who run Sea-Tac Airport.
The airport has more escalators than any other location monitored by the state. It also has the most accidents, according to the state Department of Labor & Industries (L&I).
Between 2008 and early 2014, there were 175 injury accidents on the airport's 79 escalators, state records show. That's more than half of the 318 escalator accidents reported statewide to L&I during that time.
Yet since 2008, state inspectors have blamed mechanical problems for escalator-related injuries at the airport only three times.
Instead, inspection reports usually pointed to a different culprit: Wheeled luggage.
People fall on airport escalators with luggage so frequently that state inspectors have repeatedly recommended that Sea-Tac add signs directing people away from escalators and toward elevators.
In response, the Port of Seattle – which runs the airport – has adjusted its signs in some areas, but not others.
Sea-Tac officials say there's only so much they can do to encourage people to take elevators if they're carrying too many things, or are otherwise physically impaired.
During peak summer travel periods about 100,000 travelers go through the airport each day, said Sea-Tac spokesman Perry Cooper.
"We have people focused on getting where they want to go really fast," said Stuart Mathews, general manager of aviation maintenance at the airport. "That's really the much harder piece to deal with on this, the human element."
In some places, adding signs can cause people to stop abruptly, creating additional traffic flow problems, Mathews said. And it wouldn't be physically possible to move everybody through the airport using only the airport's 82 elevators, he said.
Even so, state officials would like to see port officials do more, such as putting warning signs on the floor, or adding more overhead announcements advising people to take elevators if they can't hold the escalator hand rail, said Jack Day, L&I's chief escalator and elevator inspector.
The airport plays announcements discussing escalator safety four times an hour. They include messages to not bring strollers or pets on the escalators, as well as to face forward while riding. None specifically warn against bringing wheeled baggage on the moving staircases.
Day said he would rather avoid imposing any kind of blanket regulations on signage around airport escalators. State officials understand that an approach that works in one area might not work in another, he said.
L&I inspectors meet regularly with Sea-Tac officials to discuss ways to improve escalator and elevator safety, Day said.
Simply banning people from taking luggage on airport escalators wouldn't work, he said, due to human nature.
"People are going to do it anyway," Day said.