Students who arrive late at school on national exam days because of train delays were reminded they are not required to produce any excuse sheet as proof.

A track point fault on the East-West Line that lasted for about three hours yesterday affected commuters on their way to work and school.

It was the first day for written papers for the Primary School Leaving Examination (PSLE), with the English language exam held yesterday morning. The GCE O-level Music Performing examination was also held yesterday morning.

But there were no reports from schools of any candidates who were affected by the train service disruption, said the Singapore Examinations and Assessment Board (SEAB).

This is the second time that there have been train delays on the day of a PSLE exam. On Aug 18, some candidates taking the PSLE oral examination reported late due to a train disruption on the North-South Line and Downtown Line.

SEAB said that it has been working with schools to advise candidates to plan for sufficient travel time, and the steps that they should take if affected by train service disruptions. Candidates would be given the full duration of time for the paper, no matter what time they start, it said.

"SEAB would like to assure examination candidates that they will not be penalised for being late if they have difficulties getting to their examination centres on time due to such disruptions," added the SEAB spokesman.

Transport operator SMRT said the fault was not linked to the new signalling project.

It first tweeted at 5.53am that commuters should expect another 30 minutes of travel time from the Tanah Merah to Pasir Ris stations. This was later revised to 10 minutes on top of the usual time taken to travel between the two stations.

Free regular bus services were offered between Tanah Merah and Pasir Ris, in addition to free bus bridging services between Tampines and Pasir Ris. Normal train service resumed at 8.37am.

Yesterday, PSLE candidates such as 12-year-old Aaliyah Sarah were forced to make alternative plans because of the delays.

The St Hilda's Primary School pupil realised that there was a delay when she arrived at Pasir Ris MRT station around 6.30am and called her parents, who drove her to her school in Tampines. She arrived at 6.55am, 20 minutes before the assembly time of 7.15am.

"Luckily my parents could give me a lift on their way to work. If I were late for the exam, I would be more nervous and it may affect how well I do in the paper," she said.

Her father, an aircraft technician, ended up 20 minutes late for work.

Junyuan Primary School pupil Xiong Junhan, 12, said he took 15 minutes longer to get to his school in Tampines from his home in Paya Lebar, but made it for his PSLE paper. "I was really fearful that I would be late, which would make me even more stressed during the exam. I wouldn't be able to focus and would take longer to think of the right answers," he said.

• Additional reporting by Sue-Ann Tan