Seoul Metro Line 1 Train Signal Device Improvement Results in Zero Emergency Stops

Seoul Metro Upgrades Line 1 Train ATS Onboard Signal System from Analog to Digital
Prevents Emergency Braking, Reduces Passenger Falls and Safety Incidents from 22 to 0, Compensation Costs from 13 Million Won to 0
Project Justified by Anti-Corruption and Civil Rights Commission's Active Administration Request... Commission Visits Metro to Encourage
President Baekho Thanks Active Administration System for Preventing Major Citizen Disasters and Leading Public Interest Solutions

Kim Hong-il, Chairman of the Anti-Corruption and Civil Rights Commission, is passing through a Seoul subway ticket gate.

The sudden stops on Seoul Subway Line 1 have been dramatically improved.

Seoul Metro (President Baek Ho) announced that by converting the signaling devices of Line 1 trains to a digital system, the annual average number of sudden stops caused by signal abnormalities, which used to reach around 2,200 cases, has been reduced to zero.

This improvement was realized by reflecting the opinions of citizens submitted through the Active Administration National Petition system operated by the Anti-Corruption and Civil Rights Commission.

Until now, Line 1 frequently experienced emergency braking due to train signal device errors. From 2020 to 2022, over three years, there were 6,700 sudden stops caused by signal device problems on the Line 1 operation section (Seoul Station to Cheongnyangni Station). This led to numerous complaints about passenger falls, train delays, and safety concerns.

The Metro held a special committee to identify the causes of emergency braking on Line 1. It was found that as customer convenience and safety facilities such as underground tunnels, station amenities, and platform screen doors were added, abnormal frequencies generated from these facilities were received by the train’s signaling devices, causing signal malfunctions and resulting in sudden stops.

To address this, it was necessary to modify the train’s signaling devices. However, since Line 1 trains are scheduled to be replaced with new electric trains starting in 2026, there were internal and external views that modifying the signaling devices might lead to budget waste. The citizen petition submitted through the Active Administration National Petition system played a decisive role in justifying the project.

The petitioner stated, “I use Line 1 for commuting, and as the train approaches the station, it suddenly stops with announcements frequently indicating it is due to signal abnormalities. Elderly passengers, women, and those who cannot hold onto handrails find it difficult to maintain balance, and if this continues, it could lead to serious accidents. I request prompt action.”

To fundamentally prevent sudden stops and ensure passenger safety, the Metro began phased modifications of the signaling devices on electric trains starting in April 2022. With an investment of about 6 billion KRW, the ATS onboard signaling devices installed on 16 train sets of Line 1 were converted from analog to digital systems. The digital system minimizes the impact of external interference signals such as abnormal frequencies occurring in tunnel environments.

ATS (Automatic Train Stop) is an automatic train stopping system. The ATS system operates by receiving signals from transmitters installed on the tracks via onboard signaling devices. If abnormal frequencies are received for any reason, the system automatically stops the train to prevent danger.

Since the completion of the modification work in September this year, there have been no sudden stops caused by train signal device errors on Line 1. From October 2022 to February 2023, over four months, the number of safety accident victims such as passenger falls decreased from 22 to zero, and compensation related to accidents dropped from 13 million KRW to zero. The Metro expects that improved ride comfort will also positively impact customer satisfaction.

Chairman Kim Hong-il of the Anti-Corruption and Civil Rights Commission and Baek Ho, President of Seoul Metro (right)

In this regard, Kim Hong-il, Chairman of the Anti-Corruption and Civil Rights Commission, Kwon Geun-sang, Director of the Policy Bureau for Rights Improvement, spokesperson Lim Gyu-hong, and five others visited the Metro on the 1st to observe the excellent case and encourage proactive work efforts.

The Metro introduced the improvements made to the Line 1 train signaling devices and shared issues regarding inconveniences faced by transportation-vulnerable groups in using preferential tickets, which were pointed out during this year’s National Assembly audit, conducting a demonstration of preferential ticket use at Janghanpyeong Station. The visiting group then moved to Gunja Train Depot, where Line 1 trains are maintained, to tour inspection facilities and others.

During the National Assembly audit, there were complaints about inconvenience caused by the subway turnstiles’ lighting and voice announcements that distinguish ticket types (regular tickets, free ride preferential tickets).

Besides the improvement of the ATS onboard signaling devices on Line 1 trains, the Metro has resolved four other Active Administration National Petition cases through recommendations from the Anti-Corruption and Civil Rights Commission.

Baek Ho, President of Seoul Metro, said, “Thanks to the Active Administration National Petition system of the Anti-Corruption and Civil Rights Commission, we were able to actively resolve the train signal abnormality issue, raising the safety level of Seoul Subway and preventing major citizen disasters. We express our gratitude to the Commission for understanding citizens’ inconveniences and playing a leading role in solving public interest issues.” He added, “We will continue to prioritize safety, listen carefully to citizens’ voices, and strive to thoroughly reflect them in subway operations.”

This content was produced with the assistance of AI translation services.