Expressway Monitoring and Advisory System

The Expressway Monitoring and Advisory System (Chinese: 电子监控与信息系统), also known by its acronym of EMAS, is a computerised system that is used to monitor traffic on Singapore's expressways. EMAS enables Land Transport Authority (LTA) personnel to detect accidents and respond to them more quickly. In addition, it notifies motorists of adverse traffic conditions.

The contract for the construction of EMAS was awarded by the LTA to Singapore Technologies Electronics in December 1996. The first phase, implemented only on the Central Expressway, was launched officially on 21 March 1998 by then Minister of State for Communications, John Chen. In addition, tunnels were originally used by General Electric between 1991 and 1999. The system was extended to every expressways after the trial, in 2000:

Separately, the checkpoints utilized EMAS signboards through General Electric and which is located at -

The upgrading of EMAS signages was announced in September 2013. It will be rolled out to Central Expressway (both blue screens and tunnels), East Coast Parkway, and Bukit Timah Expressway/Seletar Expressway that is near to the Woodlands Checkpoint, which was completed in October 2014. The second phase will be rolled out to Ayer Rajah Expressway and Kranji Expressway, which was completed in August 2015. The third phase will be rolled out to the remaining expressways, which was completed in February 2016.

EMAS consists of a network of electronic cameras and LED signboards located at strategic points along the expressways. The cameras transmit data to the ITS Centre, located at Clemenceau Avenue. In the Centre, staff monitor the data 24 hours a day, looking out for signs of accidents. When an accident occurs, the appropriate agencies, such as the Traffic Police and SCDF, are notified. Warning messages are then displayed on the signboards to inform motorists of the accident and allow them to make alternative travel plans. When the expressways are free of accidents, the signboards are used to display other informational messages, such as road safety reminders, planned road closures, or road works.

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