The fully automated line is operated by Metro Trains Sydney,a private consortium led byHong Kong’s MTR Corporation, John Holland and UGL. The operator has been handed control of the city section of the Metro City and Southwest line between Chatswood and Sydenham ahead of its planned opening on August 4.

At present,trains are running the entire length of the line from Tallawong to Sydenham,but passengers have to get off at Chatswood.

A review of Saturday’s shutdown by another Fire and Rescue commander was also critical about the lack of a liaison officer at the operator’s emergency services control room at Tallawong. “This was a significant failing that could have had a significant impact on emergency service operations and safety of emergency services staff,” they said.

The commander was scathing of a call from a metro controller requesting only one fire engine attend Cherrybrook station. “[It] was misleading and potentially could have had an adverse effect on operations,” their assessment said. “The incident was on a much larger scale than reported and may have required additional specialist resourcing.”

The commander also warned that the outcome could have been “considerably worse” if it had happened on a warm day,“potentially resulting in numerous conditions including dehydration,exhaustion,heat stress,medical emergencies,patient distress”.

A 30-year-old woman who was among the passengers trapped on the trains was treated by paramedics after suffering a panic attack.

Sydney Metro,the government agency overseeing the rail projects,said the response time to remove passengers from trains was unacceptable,and it would be asking the private operator to review how incidents were managed.

“This incident will be thoroughly reviewed and measures put in place to ensure MTS[Metro Trains Sydney] follows appropriate procedures,” it said.

Metro Trains Sydney chief executive Dan Williams apologised to passengers and said an investigation was under way,acknowledging that it took too long to resolve the incident.

A spokesperson for Fire and Rescue NSW said it would use the incident as an opportunity to help identify improvements to ensure community safety.

However,Fire Brigade Employees Union state secretary Leighton Drury called on the national rail safety regulator to intervene before “disaster strikes”.

“We have bans in place to protect commuter and firefighter safety alike. These are serious matters,and we refuse to be rushed by political deadlines,” he said.

Last week the unionslapped an indefinite ban on members taking part in critical safety drills and other exercises on the new city section of the metro rail line due to concerns about a lack of permanent funding for firefighting resources for the new line.

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