The train pulls into Pennsylvania Station during the morning rush, the doors open and you make a beeline for the escalators.
You stick to the left and walk up the stairs, figuring you can save precious seconds and get a bit of exercise.
But the experts are united in this: You’re doing it wrong, seizing an advantage at the expense and safety of other commuters. Boarding an escalator two by two and standing side by side is the better approach.
It may sound counterintuitive, but researchers said it is more efficient if nobody walks on the escalator.
To be clear, this is not better for the escalator itself, although that has been a matter of dispute.
The question of standing versus walking flared up recently in Washington, D.C., after the general manager of the Metro, Paul Wiedefeld, said the practice of walking on the left and standing to the right — as outlined in the Metro’s rules and manners — could damage the escalator. The escalator company Otis said that was incorrect, an NBC affiliate reported, and Mr. Wiedefeld clarified that standing two abreast would be safer and reduce the chance of falls if everyone did it.
For its part, Otis said in a statement that its longtime position has been that passengers should not walk on escalators, as a matter of safety.
“Codes and standards vary from jurisdiction to jurisdiction, but our recommendation is for escalator passengers to step on, hold on to the rail and stay alert,” the company wrote.
The Metro is not the first mass transit operator to try to address this issue.
Last year, the London Underground promoted an experiment at its Holborn Station, one of London’s busiest, with more than 56 million passengers a year and escalators that are 77 feet tall.
The plan? To change passengers’ behaviors and get them to stand side by side riding — not walking — during peak periods.
The Underground had concluded that in stations with escalators taller than 18.5 meters, or about 61 feet, much of the left side went unused, causing blockages and lines at the bottom. The Underground campaigned to fill the available space on the escalators with people, rather than leaving the left side of each step largely empty, except for those who chose to hike up.
An experiment in 2015 at the station found that standing on both sides of an escalator reduced congestion by about 30 percent.
Consultants at Capgemini Consulting in London explored the efficiency question by timing themselves over several days walking and standing on an escalator at the Green Park station and then using that data in computer models.
They found that walking up the escalator took 26 seconds compared with standing, which took 40 seconds. However, the “time in system” — or how long it took to stand in line to reach an escalator then ride it — dropped sharply when everyone stood, according to a blog post by the researchers.
When 40 percent of the people walked, the average time for standers was 138 seconds and 46 seconds for walkers, according to their calculations. When everyone stood, the average time fell to 59 seconds. For walkers, that meant losing 13 seconds but for standers, it was a 79-second improvement.
Researchers also found the length of the line to reach and step onto an escalator dropped to 24 people from 73.
Why do the outcomes improve if everyone stands?
“Those who stand on the right-hand side tend to use every second step, whilst those who walk are likely to take three steps per person, which wastes space,” the consultants, Shivam Desai and Lukas Dobrovsky, wrote.
So everyone should stand on an escalator instead of walk because the greater good would be served, right?
Yeah, good luck making that happen, at least in America, experts said.
Jeanine L. Skorinko, a professor of psychology at Worcester Polytechnic Institute in Worcester, Mass., said in an email that people, especially Americans, like to keep more distance between themselves and strangers “and would rather take the stair below them or walk past them.
“This is why people put bags on seats next to them on the train so people don’t sit next to them,” she added.
It would be hard to persuade people that “everybody wins” if they all merely stood on the escalator, Curtis W. Reisinger, a psychologist at Zucker Hillside Hospital in Glen Oaks, N.Y., said.
“Overall I am not too optimistic that people’s sense of altruism can override their sense of urgency and immediacy in a major metro area where the demands for speed and expediency are high,” he wrote in an email.
Sam Schwartz, New York City’s former traffic commissioner and a fellow in transportation at Hunter College, said people’s competitive nature tends to trump logic and science.
“In the U.S., self-interest dominates our behavior on the road, on escalators and anywhere there is a capacity problem,” he wrote in an email. “I don’t believe Americans, any longer (if they ever did), have a rational button.”