Trains will be newer, more regular and safer after the Beijing subway system gets a major overhaul.

The measures that were first reported in Beijing Daily include the replacement of old trains, installation of screen doors and safety barriers at all subway stations and the shortening of the interval between trains to just two minutes.

Jia Peng, a spokesperson for Beijing Subway, confirmed the upgrade was on the way in an interview with METRO yesterday.

The improvements, which will take place over the next four years, will try to get the most out of all subway lines in light of the imminent opening of five brand new urban-rail lines that will feed into the grid this year, said Liu Jian, deputy chief manager of Beijing Subway.

The subway operator says the system now handles five million riders a day.

During peak hours, some subway stations are currently limiting passenger flow in a bid to cope with the massive number of commuters.

The program is aimed at easing the lengthy wait at some stations and the need for overcrowded trains during rush hour.

Stations along lines 1 and 13 and the Batong line will all be equipped with screen doors and safety barriers to ensure people on the platform are unable to fall onto the train tracks.

The upgrade will also include adjustments to the signal system and power supply, also aimed at improving safety and the service level.

Beijing Rail Traffic Control Center says Line 1, with 1.2 million daily riders, is now the busiest line in the world. Some 114 trains, which have been in use for more than 20 years, still run on the line.

The upgrade project will see the old trains replaced and the 174 newer trains - built in 1998 - will be fitted with air-conditioning systems. Twenty-two new trains will be put into use on Line 5.

MRT Corporation Limited will add 13 trains to help shorten the interval as a part of the upgrade.

After the improvements, the interval between trains on lines 1, 4 and 5 will be two minutes.

In addition, a new transfer link will connect Line 13 with Line 10 at Zhichunlu Station. Two new stations, Tsinghua Donglu and Jiancaicheng East, will also be added to Line 13.

Longer platforms will be used on stations along lines 6, 7 and 14 - which are lines that are all under construction.