'Smoke' fills MRT train and station after leaks from air-con
Plumes of "smoke" came out of a train when the doors opened after it pulled into Tanjong Pagar MRT station yesterday.
It filled the station as commuters rushed out, their hands cupped over their mouths and noses.
Passenger Sophia Kee told The Straits Times Online that the cabin she was in became "smoky" during the journey between Raffles Place and Tanjong Pagar stations.
It appeared to be "coming from underneath the train", between the train and the tracks, and filled the train and the station, she said.
"It was really strong, thick smoke."
The 30-year-old environmental designer told ST that she and the other passengers did not know what to do when the train stopped and the train doors opened.
"We did not know if it was more dangerous on or off the train," she said, adding that the "smoke" made her cough.
She also said that there were no announcements telling passengers what to do while she was there.
After about a minute, Ms Kee decided to get off the train and walk to her office in Outram Park.
As she left, she saw SMRT staff members arriving to help the passengers.HARMLESS: SMRT said the 'smoke' was inert gas freon. The SCDF sent firemen to Tanjong Pagar MRT station as a precautionary measure.PHOTOS: ISKANDAR ROSSALI, STOMP
Another commuter, who did not want to be named and who was at the platform when the affected train arrived, told The New Paper that the SMRT staff members asked everyone to stop taking photographs and videos.
Police on patrol also began ushering people to the concourse.
The incident was captured on video by several passengers and shared on social media platforms.
SMRT later clarified that the "smoke" was freon gas that had leaked from the train's air-conditioning system. (See report below.)
It said: "The discharge of freon into the tunnel reduced visibility at parts of the station when the platform screen doors were opened for passengers to exit the train."
SMRT staff responded by immediately switching on the tunnel ventilation system to disperse the gas.
The Singapore Civil Defence Force, alerted to the incident through a video submitted by a commuter, sent firemen as a precautionary measure.
It said there was no fire detected at the platform and there were no signs of smoke.
The passenger who spoke to TNP said that she, along with others, got on the next train that came five minutes after the affected train left.
On her way to Tiong Bahru MRT station, she continued to see "smoke" coming towards her cabin from the front of the train.
She said: "It was a little unbearable in the train because of the smoke but most commuters were calm and simply covered their mouths and noses."
Police said the affected train had been towed to Ulu Pandan Depot for inspection.
In its statement, SMRT said the passenger platform at Tanjong Pagar MRT station remained in service during the incident and that train services were not affected.
It also apologised to affected passengers and said that it would be investigating the cause of the incident.HARMLESS: SMRT said the 'smoke' was inert gas freon. The SCDF sent firemen to Tanjong Pagar MRT station as a precautionary measure.PHOTOS: ISKANDAR ROSSALI, STOMP
Expert: Scene looks scarier than it really is
Freon, the gas that caused the scary scenes at the Tanjong Pagar MRT station, is not particularly hazardous, said an A*STAR director.
Dr Keith Carpenter, executive director of the Institute of Chemical and Engineering Sciences in A*STAR, said freon is a trade name for a range of gases.
These gases are virtually odourless, non-flammable, inert and not particularly hazardous.
They are mostly in liquid form as refrigerants in fridges, freezers and air-conditioning units.
Dr Carpenter said: "What you see in the video happened because when released, freon is vapourising and cold."
In general, exposure to the gas needs to be at above 10 per cent in air and for a prolonged period for it to have major health effects.
"The incident looks dramatic, but it really looks scarier than it really is," he added.