The National Transport Workers' Union (NTWU) yesterday submitted an appeal to rail operator SMRT against the dismissal of two workers who were involved in a fatal track accident earlier this year.

Train driver Rahmat Mohd, 49, and another SMRT employee who has not been identified, were sacked over the incident in which two trainees were killed.

NTWU executive secretary Melvin Yong said the union had reviewed the cases and raised further queries in its appeal to SMRT.

"As we await the reply from the company on their decision, we will continue to render the necessary support and assistance to the affected employees during this difficult time," he said in a statement.

Mr Rahmat, who was dismissed last Tuesday following an internal inquiry, was driving the train that hit and killed the two men near Pasir Ris MRT station on March 22.

Mr Nasrulhudin Najumudin, 26, and Mr Muhammad Asyraf Ahmad Buhari, 24, were part of a 15-man team sent to investigate a possible fault with track equipment.

The other employee who was fired is believed to have been part of the work team on the tracks.

SMRT said in April that several safety lapses were found, including allowing the train to ply in automatic mode. Watchmen who were supposed to keep a lookout for trains were also not deployed.

Besides the dismissals, warnings were issued and performance grades were "recalibrated downwards across various levels of the Trains team, including senior management", the company told staff.

SMRT said it will be examining the appeal in accordance with "established processes", but did not elaborate on what these are.