SMRT Corp's latest statement on the tragic accident that claimed two young lives points to a safety lapse on the part of the maintenance crew.
It said the crew must coordinate with the station for oncoming trains to be halted before any track crossing takes place, and that there was no record of this procedure having taken place on the fateful day.
Was this why Mr Nasrulhudin Najumudin, 26, and Mr Muhammad Asyraf Ahmad Buhari, 24, were hit and killed on Tuesday morning by a train that was travelling at 60kmh in auto-drive mode?
It would be most unfortunate - and downright scary - if our rail safety protocol allowed a single lapse to result in a fatal outcome.
Railway tracks are hazardous places to be on foot - with intersecting metal rails, loose gravel, sleepers, bolts, brackets, fasteners and cables to trip over - even when trains are not moving.
But when trains are plying, they can be as dangerous as a loaded weapon. So any safety protocol governing the deployment of work crew during service hours would have to include a number of fail-safes - so that if there is a lapse (or even two), tragedies can be avoided.
SMRT is not shedding more light on the incident beyond what it has said in its latest statement.
It would, however, not be unreasonable to say that there were several safety lapses - and not just the one that SMRT pointed to in its statement. Because the alternative - to assume the safety protocol was not multi-layered - would simply be unthinkable in a place like Singapore.
According to experts, trains approaching a worksite would have to be driven in manual mode, and moving at a crawling speed.
This makes perfect sense because a train, unlike a road vehicle, cannot steer away to avoid collision. And a fully laden six-car train weighs close to 300 tonnes, and would require well over 100m (about the full length of a football field) to stop if it was moving at 60kmh in dry weather.
If it was moving at a crawling speed, the stopping distance would have been drastically shaved.
It is also imperative for a driver to be in control at all times when workers are on the tracks.
A driver in control would have a clear line of sight, so he can apply the brakes when necessary. Train systems are not designed to look out for people or obstacles - except for another moving train. So, allowing a train to move in auto mode and at 60kmh near a work zone is ill-advised.
A driver at the helm is also supposed to sound the horn as soon as he spots workers from afar. That is because MRT trains, being driven by electric motors, can be relatively quiet on an open track near road traffic.
Mr Muhammad Hatin Kamil, 24, who was with his two unfortunate colleagues when they were mowed down, said: "Our environment up there is different - you wouldn't be able to hear the train coming."
Another layer of safety that is commonly employed pertains to lookouts stationed at least 50m from the work party. This would give workers ample time to get off the tracks and get back into the safe walkway area when a train approaches.
Similarly, a flag-waving signalman must be at the station headwall to warn train drivers of workers ahead.
All these steps would have been on top of a system that requires work teams to seek permission before going onto the tracks. If so, SMRT's operations control centre (OCC) would have been aware of a work team near Pasir Ris station on Tuesday morning.
Which means train drivers moving along that stretch should already have been forewarned. So, even if there were no lookouts or signalmen, drivers would already have been on alert.
Another thing, track-switching when men are on site is a bad idea as it introduces unpredictability into an area where predictability is crucial.
The OCC could also have chosen to remove speed codes along that selected stretch, thereby forcing drivers to drive in what is known as restricted manual mode. In this mode, speed is automatically capped at 18kmh.
That is what is meant by having fail-safes.
The fact that at least one man in that work team on that tragic day had to jump out of the way of the train suggests that he did not expect it to come towards him, or to come towards him at such a high speed.
That may well point to safety lapses other than the one SMRT alluded to.
By the same token, if all the safety measures had been observed religiously, the two deaths might well have been prevented.
The two who died were part of a 15-man team, so we shudder to think how far worse the tragedy could have been if more men were not on the viaduct's walkway when that train hurtled by.
Looking ahead, we can only hope that rail operators and regulators learn from this incident and therefore be in a better position to ensure there is no repeat of it.
We can meanwhile take comfort in the fact that Tuesday's incident was only the second rail accident that resulted in staff sustaining fatal injuries on the tracks in Singapore's 29-year rapid transit history.
Let us hope the relatively clean slate has been the result of strict adherence to a robust safety protocol, and not sheer luck.
Christopher Tan Senior Transport Correspondent
This article was first published on March 25, 2016.
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