Oral Answer

Lessons on Operations and Safe Distancing Measures Gleaned from 14 October 2020 MRT Service Disruption Incident

Speakers

Summary

This question concerns the 14 October 2020 MRT disruption, with Ms Joan Pereira, Mr Saktiandi Supaat, and Mr Dennis Tan Lip Fong inquiring about its causes, emergency preparedness, and crowd management. Minister for Transport Ong Ye Kung explained that the incident involved concurrent technical faults in a power cable and circuit breaker trip coil, compounded by human error in the Operations Control Centre. To prevent recurrence, equipment supplier Alstom will replace 150km of power cables and 113 trip coils, necessitating planned rail closures for maintenance works through 2021. Minister for Transport Ong Ye Kung noted that while detrainment is a last resort due to track safety risks, emergency protocols were activated and safe distancing was managed through mask-wearing and minimized talking. He concluded that the "One Transport Team" will focus on enhancing engineering capabilities and reviewing operational procedures rather than finger-pointing to maintain high rail reliability standards.

Transcript

4 Ms Joan Pereira asked the Minister for Transport in view of the recent MRT breakdown on 14 October 2020 (a) whether there are sufficient business continuity plans and emergency preparedness exercises conducted on a regular basis to ensure that the relevant teams know what to do in the event of a power failure; and (b) how long has it taken for the crowd control process to kick in and what have been the measures implemented.

5 Mr Saktiandi Supaat asked the Minister for Transport when buses or trains are stranded at peak hours (a) what are the protocols in place to ensure safe distancing measures and good ventilation for the commuters; (b) whether public transport workers are trained to guide commuters to safety and address their concerns; and (c) what are the lessons learned from the MRT disruption on 14 October 2020 with regard to crowd management and safe distancing measures and how will this be improved upon.

6 Mr Dennis Tan Lip Fong asked the Minister for Transport (a) what was the cause of the cable insulation fault which triggered the MRT disruption on 14 October 2020; (b) why did the circuit breaker in the vicinity of Tuas Link and Tuas West Road fail to isolate the cable insulation fault; and (c) why was the cable insulation fault not isolated before SMRT attempted to draw power from the Buona Vista intake station resulting in the power supply disruption to Circle Line.

7 Mr Dennis Tan Lip Fong asked the Minister for Transport (a) given its past experience, whether SMRT could have taken much less time to complete passenger recovery or evacuation during the MRT disruption on 14 October 2020; and (b) what were the reasons for the delay.

8 Mr Dennis Tan Lip Fong asked the Minister for Transport what are the key lessons arising from the MRT disruption of 14 October 2020 and what measures will be taken to ensure that similar future incidents will be avoided.

The Minister for Transport (Mr Ong Ye Kung): Mr Speaker, Sir, can I answer Question Nos 4 to 8 together, please?

Mr Speaker: Yes, please.

Mr Ong Ye Kung: The 14 October 2020 incident was significant and affected over 120,000 commuters. As with this House, I am concerned about the disruption. Our imperative must be to get to the bottom of the matter, take follow-up actions and prevent similar incidences from recurring.

The Land Transport Authority (LTA) has, therefore, investigated the incident thoroughly, with inputs from operator SMRT and the equipment supplier Alstom. They identified what went wrong and have started to address the gaps and shortcomings. On 28 October, that is, last month, LTA issued a detailed media statement and its full investigation report. Together with SMRT and Alstom, they held a joint media briefing the same day to explain the cause of the incident, the follow up actions and answered many questions. Their findings, including answers to many of the questions posed by Members, were widely covered in the media.

Mr Speaker, Sir, let me recap the pertinent points.

The disruption was caused by the occurrence of concurrent faults and one mistake.

First, there was a 22kV power cable fault in the electrical zone between Tuas Link and Tuas West Road stations. This is along the Tuas West Extension. This would not have caused a disruption if the circuit breaker, which is a protection feature of the system, had kicked in and isolated the affected electrical zone because, once isolated, the power can flow and service can continue.

But then a second fault occurred, in that the circuit breaker at Tuas West Road station, close to where the faulty cable was, malfunctioned. It was later found out that the trip coil, which is a component of the circuit breaker, was faulty.

A secondary protection mechanism at the sector level did kick in and then isolated the fault. But that cut off power supply across large sections of the North-South and East-West Lines. At that point, the Operations Control Centre then made a mistake and did not isolate the fault before drawing power from the Buona Vista Intake substation. As the Buona Vista Intake substation also supplies power to the Circle Line, this, in turn, affected train services along parts of the Circle Line.

Members have asked: why was the power cable faulty? Why did the primary circuit breaker, which is the first level of protection, not work? Why did it not work? Why did the Operations Control Centre not remotely isolate the fault before powering up?

LTA, SMRT and Alstom have given their explanations during the media briefing. The reasons for the component failures are still unknown. The faulty power cable and the circuit breaker have been sent for forensic examination by the original equipment manufacturer, to ascertain the reasons for failure.

What we do know is that there have been four power cable failures along the Tuas West Extension since 2018. LTA and SMRT had earlier expressed their concerns to Alstom, the supplier, who was forthcoming and had already agreed much earlier to replace some of the cables. In fact, work was on track to start in the later part of October.

Following this recent incident, Alstom will conduct a complete replacement of all the power cables – 150 km of it – along the Tuas West Extension. This is quite a major undertaking and will be completed progressively by the end of next year. The cables will take time to procure and arrive. At the right time, LTA will schedule early closures and late openings on weekends or full Sunday closures for limited periods in 2021 to facilitate the cable replacement works. We will announce these plans in due course.

Alstom will also replace all 113 trip coils in the circuit breakers along the Tuas West Extension by the end of this year. LTA will implement weekend early closures to facilitate the replacement exercise and we seek commuters' understanding for the inconvenience caused. During this time, SMRT will also step up the frequency of mechanical testing of the circuit breakers of this sector from annually to every six months. This is in addition to visual inspections of the trip coils once every 10 days, to ensure that they are in working order.

As for the Operations Control Centre not isolating the fault before drawing power from Buona Vista Intake substation, this was a human error. Members asked if there was a Standard Operating Procedure (SOP) in responding to such a situation. There are, in fact, many sets of SOPs to cater to different scenarios, but one thing we have learnt over the years is that every disruption is different and unique. So, besides being guided by SOPs, the engineers on duty will have to exercise judgement and make quick decisions during an emergency.

I have not been in their shoes and cannot imagine the challenges they are facing. But under the pressure of time and circumstances, the personnel involved, I believe, made an honest mistake. I have no doubt this has been a major lesson for them. They wished they had decided differently and they have much learning to share with their colleagues, so that such a mistake will not happen again.

Members also asked about evacuation and crowd control. I want to assure Members that LTA, SMRT and the Home Team jointly conduct emergency preparedness exercises every year. SMRT staff also regularly get refreshed on their roles and responsibilities during a service disruption. On the evening of the disruption, the SOPs were promptly implemented. About 400 additional SMRT staff were immediately activated to both rectify the fault and help affected commuters.

Safety of commuters is the top priority during service recovery. That is why detraining commuters is always a last resort because to have commuters walking along the track poses risk, especially for those who are elderly or handicapped. So, they need to be very carefully carried out. The Operations Control Centre, therefore, has to balance the risk posed by detrainment against the discomfort and heightened anxiety of commuters in the stalled trains. Therefore, as far as possible, the Operations Control Centre will try to restore power to the trains and then bring commuters through the trains to the nearest MRT station.

However, 40 minutes into the disruption, the Operations Control Centre concluded that it could not restore power to the system quickly and, therefore, decided on detrainment. Train captains carried out the safety protocols, and station staff walked on the tracks to the trains to guide commuters to the nearest stations. All 6,800 commuters on the stalled trains were brought safely to the nearest station platform in under an hour, except for the 78 commuters whose detrainment was delayed by inclement weather and lightning risk.

Free boarding of regular bus services was activated within 10 minutes of the incident to disperse the crowds outside the train stations. One hundred and twenty bridging buses were in place within 35 minutes of the incident and SMRT staff guided commuters to look for suitable alternative transport arrangements to carry on with their journeys.

Despite this, crowds built up around the MRT stations. This is, unfortunately, inevitable in the event of a train disruption. While there is understandably concern about overcrowding, given the current COVID-19 situation, it will not be practical to ensure physical distancing without further inconveniencing the affected commuters in such an unexpected situation. The transport team simply has to do our best to prevent such incidents from happening in the first place and to rectify the incidents as quickly as possible should they occur. Thankfully, on that evening, commuters were very cooperative. They continued to wear their masks and minimised talking to each other, and I thank the commuters for their understanding and for doing their part under such trying circumstances.

In the course of their investigations, our engineers learnt many useful lessons, to improve operations and maintenance. There are also wider, non-engineering lessons, too, for policy makers and, I think, for this House as well. I think there are three lessons.

First, mass rapid transit systems are very complex. Engineers who have worked on mass rapid transit systems and other systems, and have a basis for comparison, will very likely testify to that. Several fields of engineering converge to get a mass rapid transit system to work reliably to carry millions of commuters safely, for many hours throughout the day. Given its complexity, when a major disruption occurs, the circumstances and causes are often unique.

That leads us to the second lesson – because of the nature of mass rapid transit systems, we should never be complacent. Keep learning and keep improving. Always emphasise building up engineering and operational capabilities and experience. Regularly review SOPs and conduct staff training to ensure processes are up to date and everyone in the team knows what to do when the need arises.

Third, MOT, LTA, SMRT and SBST must work as one team. This is the spirit of the One Transport Team. We coined the term to remind ourselves of the imperative. This was how we managed to significantly improve the reliability of our MRT system, bringing the Mean Kilometres Between Failures or MKBF from under 200,000 train-km just five years ago to more than one million train-km today. With the recent disruption, the morale of the teams on the ground has taken a hit.

Nobody wishes for an incident like this to happen, but when it did, we should not let it break our spirit. There are honest and hardworking people who have toiled over the past few years to make our MRT system amongst the most reliable in the world. By believing in them and in ourselves, we can stand tall, be united again and press on with our work. So, as a team, we take collective responsibility, not finger point, and we will do our best, close the gaps and address the shortcomings. Only then can we continue to fulfil our collective mission of serving commuters well.

Mr Speaker: Ms Joan Pereira.

Ms Joan Pereira (Tanjong Pagar): I thank the Minister for the reply. I have one supplementary question. The Minister mentioned about elderly commuters. I would like to find out how SMRT took care of our elderly and wheelchair-bound commuters when the trains broke down. How did they evacuate these vulnerable commuters, especially from trains that were stuck above ground?

Mr Ong Ye Kung: I thank the Member for the question. This is one of the reasons, in consideration of elderly and wheelchair-bound commuters, that detrainment had to be a last resort. Yes, there are risks, especially for this group of commuters. But when we have to, you cannot have wheelchairs on the tracks. But on the Circle Line, in the tunnels, you can have wheelchairs because there is a side platform that you can push the wheelchair on. So, evacuation on the Circle Line is much faster. In fact, that evening, it took half an hour to evacuate three trainloads of passengers because of the side platform.

For viaducts, the North-South East-West Line, it is not as straightforward. Typically, even when evacuation and detrainment start, the rest of the passengers can walk but the elderly and those with mobility challenges will stay on the train until further manpower, including SCDF, arrives. If need be, we use stretchers to carry such passengers to the nearest station. The stations are also equipped with what we call battery-powered motorised trolleys that we can use and deploy to ferry them to the nearest station.

So, SOPs are in place. We are very careful about it. Walking on the viaduct has its risks and we will always be very careful. But most importantly, is to prevent such incidents from happening.

Mr Speaker: Mr Saktiandi Supaat.

Mr Saktiandi Supaat (Bishan-Toa Payoh): Mr Speaker, I would like to thank Minister for the answer to our questions and also to thank the One Transport team for quickly responding to the situation on that particular day and helping out commuters. I have two supplementary questions.

The first is in regard to Minister's answer earlier that it took 40 minutes before a detrainment decision was taken and thereafter the commuters got off the trains in separate moments. My question is, is there a specific SOP – because there could be rising anxiety within the trains. In my question, I was asking about good ventilation for commuters within the train itself, especially if you are stuck in the train for an hour or more before eventually detrainment, typically, how long is the SOPs before a decision is made? That is my first question.

Secondly, in regard to this incident, will companies like say SMRT be taken to task? Will there be a fine being made against SMRT for such incidents; not just SMRT, but other providers going forward, in the future, if such incidents happen?

Mr Ong Ye Kung: I thank the Member. For specific SOP, typically the guideline is half an hour; 30 minutes. But I want to emphasise you are balancing two unpleasant things. One is being trapped in a train and I can imagine the discomfort and anxiety. Whenever there is a disruption like that, the battery does kick in the train. The battery cannot power the aircon but that there will continue to be a bit of light and some ventilation through a fan. It is warm and it is uncomfortable. There is a battery that will operate for about an hour.

Within an hour, you then have to decide whether to do the other unpleasant thing which is detrainment. Detrainment, as I have mentioned, has risks. You can trip. There is a 750 volts DC, third rail, and you are walking next to it. You got to make sure you disable it, double confirm, triple confirm, quadruple confirm because it is no joke walking next to a 750 volts third rail. Then, like on that night, there could be inclement weather and then there was lightning risk. Once there is lightning risk, you should stop. Never put passengers' lives in danger. So, you are balancing between these two things. But typically, after half an hour, a decision should be made whether to do detrainment.

In this case, there was some hope that they could repower, but the repower went wrong and brought down CCL, or sections of it. So, 40 minutes later, detrainment was decided. Not an easy task but the Operations Control Centre of SMRT has to make those decisions. And I think the decisions they made that night, in terms of detrainment, was correct.

On companies that could be taken to task, if the operator has made a big boo-boo, resulting in a big disruption, of course, some of these actions would have to be looked into and there is a disciplinary framework. But I think in this case, the investigation report went up. The equipment supplier came forth, agreed to replace all 113 of trip coils, and 150 km of cable wires and within SMRT and LTA, everyone self-reflected what they could do better.

So, I think what is more important than meting out punishment, is the team able to come together, reflect upon what could be done better and take it upon themselves, take responsibility to say, "I can do things better". And together, without finger-pointing, work together to better serve commuters. The mood can easily change and go wrong. When it becomes one of penalty and punishment, then the mood changes when everyone become defensive, everyone, to put it crudely, will cover their behinds. And after a while, you do not get the best outcome.

So, as far as possible, there is a disciplinary structure and we will use it if we have to. But as far as possible, I feel, hold the team together, be able to work together for the benefit of commuters – that is a lot more important.

Mr Dennis Tan Lip Fong (Hougang): I thank the Minister for his comprehensive answers. I just have two supplementary questions. One, beyond the suspension of the two staff, will LTA look into how the SMRT or indeed, both rail operators, can improve their work processes in future to prevent or mitigate against similar staff, human error in similar situations like this?

Two, in respect of the proposed replacement cables by Alstom, whether LTA will require more stringent tests to be conducted on the replacement of the upper layer cables, to ensure that similar faults which were spotted on the current cables on the previous four occasions, as well as which caused 14 October disruption, will not be present in the future replacement cables.

Mr Ong Ye Kung: Let me answer the second question first – will more stringent tests be conducted? I think to put it in context, this set of components and equipment are not new. It has been used on other lines. And they typically have a life span of 20, 25, or 30 years. So, this is a bit premature to have four faults in the last few years, which I think explains why Alstom is stepping forward and replacing everything. I do not want to prejudge why the cable was faulty. It is going through forensics and once the results come out, I am sure it will provide insights.

But there is an SOP and there is an inspection regime for all cables and trip-coils throughout the system. For this stretch, while the components are being replaced, we will step up, double the frequency, so that we make sure it works.

As for the first question, I should I emphasise, suspension does not necessarily mean we are blaming the workers or they are being punished. Because they may not have committed wrong. If there is gross negligence, in fact, if there is wilful wrongdoing, disciplinary actions will be taken, including even bringing in the Police, if there is wilful wrongdoing. But in most operations involving live operations and in a place where there is a strong safety culture, suspensions are not uncommon. It is actually carried out, quite routinely, as a matter of professional conduct and safety protocol. You will find that in the SAF, you find it in bus operations. You have a near-miss, or a side swipe of a bus, the captain might be suspended for a week. It does not mean it is a punishment. Sometimes, it is not their fault, or even running theme parks or manufacturing plants, process plants. These are always carried out. It is part and parcel of a professional conduct of an engineering company.

The purpose, depending on the circumstances, need not always be punishment. Sometimes, it is really a matter of retraining, refresh what you have learnt, self-reflect and go back, you do better and share your learnings with your colleagues. And I think it is a good system to ensure that we keep on improving.

The question specifically asked if there would be improvement in work processes. Definitely. As I have mentioned, every time there is a major disruption, it is always unique. This time, it is also unique. SMRT has not encountered such a situation before where a cable fault, coupled with a trip-coil fault, resulting in a disruption. So, they will be improving their SOPs. But frankly, when it happens, you do not have time to go and refer to them. It has to be internalised into the experience and lessons learnt by all the operators, and by the engineers. And I think this incident provided a lot of lessons for them.

Mr Speaker: Mr Pritam Singh.

Mr Pritam Singh (Aljunied): I thank the Minister for that broad-ranging explanation as to what occurred. Just one supplementary question specific to the faulty cable. The Minister mentioned that the cable is now being forensically examined as to the reason its failure. For the earlier episodes of cable failure, was it a consistent reason as in there were not two or three different reasons so that the OEM could not identify why the cable is failing in the same way, or could this have been pre-empted to an extent if the earlier cable failures were all down to the same reason or same cause?

Mr Ong Ye Kung: There were four. Two was when the system was first commissioned; that was 2018. So, of course, there were concerns. In 2019, there were no failures.

And this year, there were two earlier failures, now this one. So, the reasons for the failure has not been established which is why, given that what has happened, we should send it for forensic examination and understand the reason why.

In the meantime, regardless of the reason, the cables would be replaced.

Mr Speaker: Mr Lim Biow Chuan, next question.