Recently, the Beijing subway has added "yellow footprint" signs on some escalators, advocating that citizens should "stand firm and support themselves" instead of "walking left and standing right". Yesterday, the Beijing Municipal Administration for Market Regulation invited technical experts from the Beijing Special Equipment Inspection and Testing Research Institute to visit the Beijing South Subway Station. Based on on-site physical and data analysis, they revealed potential risks and hazards of elevator "left running right standing" from three aspects: equipment safety, passenger risk, and operational stability. In front of an escalator at Beijing South Station on Metro Line 14, Han Zhiguo, a senior engineer at the Beijing Special Equipment Inspection and Testing Research Institute, first explained the difference in height between ordinary staircase steps and escalator steps through a set of measured data. The step height of a regular staircase is about 15 centimeters, while the step height of an escalator is about 24 centimeters. Passengers rushing on the running escalator may easily fall due to the higher steps. Han Zhiguo emphasized that especially during peak morning and evening traffic, falls caused by walking on one side may cause a "domino effect" and threaten the safety of surrounding passengers. The on-site staff presented the potential risks of "left to right standing" to passengers by dismantling the escalator steps. The rollers on both sides behind the escalator steps are responsible for supporting the operation. Long term standing on one side will cause the roller on that side to bear overload pressure, leading to increased wear and shortened service life of the roller. The other side of the drive chain attachment may cause the steps to shake or even fall off due to frequent load impact, "said Han Zhiguo. In addition to the wear and loss of roundness of the step rollers, another situation may also occur in long-term "left to right standing". When passengers stand on the right side in a concentrated manner, the driving chain on one side of the escalator will continue to bear the load, resulting in a difference in the length of the chains on both sides, which may trigger the safety protection device and cause forced stopping of the escalator. Sudden elevator stops not only affect traffic efficiency, but may also cause passengers to fall or collide due to inertia, resulting in secondary injuries, "said Han Zhiguo. Such faults take a long time to repair during peak hours and have a significant impact on subway operations. Han Zhiguo also reminded passengers to stand up when taking the elevator, grip the handrail tightly throughout the journey, and avoid leaning against the wall panel or leaning over to look around. Passengers with children should hold their children and not let them climb the escalator or slide on the outer cover of the escalator. When carrying large luggage, it is recommended to prioritize using a vertical ladder. If there is a dense flow of people, it is necessary to maintain at least one step distance from the passengers in front. When reaching both ends of the escalator, one should quickly get up and down, and not wait at the entrance or exit. The buffer area of the escalator is limited, and waiting can lead to overcrowding, which can easily cause passengers to fall and step on it. Once encountering an emergency situation such as someone falling or getting injured, you can press the emergency stop buttons on both ends and seek help from the staff in a timely manner. (New Society)