THE Mass Transit Railway Corporation (MTRC) is to install a safety device on all its trains to reduce the chances of carriages separating to one in 100 billion.
The secondary coupling device will be fitted to all MTR trains by next April - the first anniversary of the worst incident in the company's 14 years of operation.
On April 27, this year, three carriages became detached in a tunnel, leaving thousands of rush hour commuters stranded in north-west Kowloon.
MTRC operating engineer design manager John Gretton said the new safety precaution would cost the company between $3 million and $5 million.
But he said it would save the company money in the long term.
Before that incident the chance of train carriages parting was one in a billion, he said. Since then every train was checked each night, which was both time and labour consuming, he said.