In 2002, Liao was transferred to Line 13 and had to relearn some of the basics of the job, such as the procedures of the new route and how to operate the different trains.

Because the trains on Line 13 run above ground, dealing with weather conditions was a new obstacle and a skill that he'd need to master.

In summer 2007, Liao was driving a train toward the Xierqi station when he spotted an unknown object on the rail. He put on the brakes immediately, stopping about 1 meter in front of it. Upon inspection, he found the object was a piece of braided fabric, about 35 meters long, 1.5 meters wide and 1 centimeter thick, that had been blown onto the rail by the wind.

If Liao had hesitated to stop, the subway could've derailed.

"As a qualified driver, you must unite with the train, that is, the train is a part of my body and I am also a part of the train," Liao explained, using a sentence he often said to his colleagues.

In the nearly 30 years of being a metro operator, Liao has never had a dispute with a passenger. "I treat every passenger as if they're my relative. If time permits, I let each person get on or off the train at their leisure."

Liao always puts his passengers' lives and property first.

He even stopped an armed thief once. The thief, who was trying to steal a passenger's wallet, panicked after being spotted and put a knife to the passenger's throat. Liao, who had just started his shift, jumped on the thief while he wasn't looking and managed to wrestle the dagger away from him.

Beijing's safest metro operator has received many honors. In 2009, he was awarded with the Golden Handshake, the highest honor given to operators with the Beijing Subway Company, and in 2013, the Beijing Federation of Labor Unions presented him with the Capital's Labor Medal.

He is meticulous at his work, and his life is also rich and colorful. "I try to stay in shape. I play table tennis several times a week and sometimes call on my colleagues to help me strengthen my exercise routine."

Liao said that he plans to keep up his legacy as the metro's safest operator and that he will challenge himself to achieve new heights in the future.