Another controversy! Should we "walk on the left and stand on the right" when taking an escalator? Here comes the scientific explanation

Recently, a netizen from Xi'an said that when taking the subway, he saw that some platforms "only have elevators but no stairs", so that some people in a hurry were blocked by two people sitting in the elevator side by side and could not go upstairs quickly. He suggested that in places where there are no stairs but only elevators, people should stand on the right to leave the road on the left for people in a hurry.

On August 24, Xi'an Rail Transit Group Co., Ltd. stated that it does not recommend walking or running on a running escalator, nor does it recommend "walking on the left and standing on the right." It also posted "Safety Instructions for Using Escalators" next to the escalator to remind the general public to ride the escalator safely. As for why the practice of "walking on the left and standing on the right" is not recommended, Xi'an Metro also gave an explanation. On the one hand, it is for safety reasons, and on the other hand, such practice is likely to cause equipment failure.

Previously, some netizens suggested to Chengdu Metro to remind passengers to "walk on the left and stand on the right" when taking escalators. Chengdu Metro responded clearly: It is not recommended!

Escalator at a subway station. Photo by Beijing News reporter Wang Guibin

"Walk on the left, stand on the right" means standing on the right side of an escalator, leaving the space on the left for passengers on the way or for emergency passages. This practice can be traced back to the "Stand on the right" sign in the London Underground in 1944. It later became an international practice and was introduced by many cities in China. It is even called "an important yardstick for measuring urban civilization."

However, in recent years, the practice of "walk on the left and stand on the right" on escalators has exposed many drawbacks and safety risks, and the operating efficiency is not high, so both at home and abroad have begun to correct this concept. According to relevant public information, Toronto, Canada, has removed the "walk on the left and stand on the right" slogan on escalators because more than 100 people are injured on escalators every year; South Korea has also cancelled the "walk on the left and stand on the right" rule on escalators in Seoul subway stations; Japan is working hard to promote the "safe and correct" way to take escalators, and its theme is " Escalator, don't walk, don't run ".

In China, subway operators in places such as Beijing, Shanghai, Guangzhou, Chengdu, and Nanjing no longer encourage citizens to "walk on the left and stand on the right" when riding escalators. Beijing Metro has cancelled the "walk on the left and stand on the right" reminder for escalators since 2018, and has vigorously promoted and guided passengers to " stand firmly and hold on " and " pay attention to safety under your feet " when riding escalators.

In 2019, Shanghai Metro released the "New Version of Escalator Riding Instructions", canceling the previous advocacy of "walk on the left and stand on the right" and adding " no walking or running while riding an escalator ". In recent years, the Hong Kong Metro has also stopped advocating "walk on the left and stand on the right", and replaced it with the slogan "hold the handrail and stand still".

Why is it not suitable to walk while riding an escalator?

The step height of an escalator is different from the step height of stairs. According to the currently implemented national standard (GB16899-2011), the step height of an escalator is generally 21cm and the maximum should not exceed 24cm, which is 13cm-18cm higher than the design height required for stairs in public places.

Image source: CCTV.com

According to regulations, the step depth of an escalator cannot be less than 38cm, which is much higher than the national minimum step width requirement of 22cm for ordinary stairs.

Generally speaking, the speed of elevators in shopping malls is 0.5 meters per second, while the speed of elevators in subways is a little faster, about 0.65-0.7 meters per second, and are considered "high-speed elevators."

Image source: CCTV News

From the design principle of escalators, the slope of escalators is a little higher than the height of stairs in daily building mechanisms, and is not suitable for walking. If people walk on escalators, it is easy to step on empty space or trip, and it is easy to squeeze into other passengers on the escalator during walking, causing accidents.

Wu Bin, an elevator expert and senior engineer, said that the "walk on the left and stand on the right" method will cause a balance deviation, resulting in a lighter load on the "left" side of the elevator and a heavier load on the right side, which will cause the elevator to tilt.

Therefore, when riding an escalator, you just need to stand firmly and hold on to it. For passengers who are in a hurry and need to pass safely and quickly, the best way is to take the stairs.

Walking on the left and standing on the right does not improve traffic efficiency

The original intention of “walk on the left and stand on the right” is to leave space for others to pass through, but in actual operation, people’s good intentions often result in “empty space on the left and standing on the right”.

During peak hours, the density of passengers on the escalator is high and the walking space is limited. If a large number of passengers are still walking on the escalator at this time, it will cause congestion and chaos, thus reducing the traffic efficiency.

As early as 2006, Assistant Professor of Architecture at City University of Hong Kong Su Tingbi wrote an article pointing out that passengers can only save a few seconds walking on escalators, which is not very helpful in increasing the capacity of elevators; calculations by London traffic engineering experts show that at London's very busy Holborn Station, if everyone stands on both sides of the escalator, it can accommodate 31 more people per minute, or 24% more passengers. Another well-known French consulting company Capgemini's research conclusion is: standing on both sides saves more time than "walking on the left and standing on the right", which benefits most passengers.

95% of escalator damage is due to uneven force

"Walk on the left and stand on the right" will cause the load on the escalator on the "left" side to be relatively lighter, and the load on the right side to be heavier, which will cause a tilt.

The components on the right side of the escalator steps (such as rollers, step chains, etc.) will be subject to more mechanical wear, which can easily lead to shortened component service life and failure.

Image source: Hubei Emergency

According to a survey, more than 80% of escalators in China have more severe wear on the right side than on the left, causing the steps to tilt slightly. According to the operating data of Nanjing Metro Operation Company, long-term "walking on the left and standing on the right" has caused great damage to the elevator, and 95% of the damage to the elevator is caused by uneven force on the elevator.

Beware of these danger zones

There are dangerous areas on escalators that can easily "bite" people. Be careful when riding an escalator, as some actions are very dangerous.

Image source: National Emergency Broadcasting

Do not lean against the side skirt of the escalator;

Keep your hands, feet, hem of clothes, etc. away from the gap between elevators to avoid accidents of being caught in the gap.

Do not walk or run quickly on the steps, and do not walk against the flow;

Do not lean your body out of the handrail to avoid collision or falling;

Do not insert sharp objects such as crutches into gaps or grooves in the elevator;

Do not climb on handrails or inner or outer covers;

When leaving the escalator, do not stop at the escalator exit to talk or look around to avoid collision with people behind you.

Source: The Paper, Beijing News, Rednet, Digital Beijing Science Center, CCTV.com, Huasheng Online