We thank Mr Wong Shao Voon for his suggestions (“Replicate signal interference during tests of new system on N-S Line”, 17 November 2016).

The Land Transport Authority would like to assure Mr Wong that the safety and reliability of the train system is our absolute top priority. As the signalling upgrade for the North-South and East-West Lines is a complex project, more than 1,300 tests will be carried out before the upgraded system is certified safe for operations, which is significantly more stringent than industry standards. These include simulations to ensure that the new system responds quickly and effectively to unexpected conditions such as sudden loss of communications signals. Learning from the experience of other international operators, we are also catering more time to test the system and iron out any issues before its full operationalisation.

Since August 2016, we have also commenced trial runs of trains on the new North-South Line signalling system with SMRT, after service hours. This will help familiarise SMRT staff with the operations of the new system and to validate operating procedures before the switchover in the first quarter of 2017.

Tan Yih Long
Project Director, Re-signalling
Land Transport Authority