With authorities here in Beijing mulling potential changes in both pricing and security on the city's subway system, many questions remain about the impact it will have on the often-overcrowded lines.

To that end, our Li Dong takes us through what taking the subway in Beijing is generally like for both passengers and staff.

Reporter

Since June 2013, the 14 subway lines in Beijing receive an average of 10 million trips every workday, making the subway stations over-crowded, especially during rush hours on workdays. The large number of passengers put huge pressure on the city's subway system.

At 03:00, subway driver surnamed Ruan started to make preparation for the first train of the subway line one. And the first train set out at 04:58.

Passengers started to enter Xi'erqi station at 06:00. And for the station master on duty Li Siye and her colleague, prelude to the morning rush hour had just started.

"We always say that this is a smokeless war. It almost is. It's like a hassle every morning,"

The station became over-crowded at about 07:30 when most of the passengers were in a hurry. Li Siye and her colleagues were also busy keeping the station in order and guaranteeing the safety of the passengers when they were trying to get on or off the trains in the crowds.

The transfer station of Xi'erqi is also the link of Beijing downtown and outer suburban district. Therefore, the station receives an endless stream of passengers on every workday. It always happens that passengers who have just stepped off the train to get off are pushed back by the stream of passengers who are trying to get on.

"There are always passengers who fail to get off the trains, especially when the train is over-crowded. They have to get off at the next stop and take another train to come back. They are in a hurry every morning. If they fail to get off the train, they will probably be late,"

Li said that she and her colleagues always make their best to help every passengers to get on and off the trains as far as possible, and keep their safety as well.

Statistics from the Beijing Subway Company show its system carried 2.74 billion passengers in 2013, a 30 percent increase compared with 2012.