THE union for rail workers has issued a blanket ban on its members maintaining or operating trains it believes are at risk of "catastrophic brake failure".
Queensland Rail is yet to say if or how this would affect commuter services.
It is the class of train - understood to make up about one-third of QR's fleet - that crashed into Brisbane's Cleveland station this week.
It caused 24 minor injuries and is now under investigation by QR, the Queensland Department of Transport and the Australia Transport Safety Bureau.
Rail Tram and Bus Union state secretary Owen Doogan said although a full investigation was yet to produce any results, there had been complaints about the trains.
Mr Doogan said the work ban would not apply to other trains used by QR.
He said "it was a fact" the driver of the crashed train was unable to activate the main or back-up brake.
"There have been complaints in these particular trains logged.
"These are the newest trains into QR."We believe there in an intermittent fault in the braking systems."
The union secretary said it was not his intention to inconvenience the community, but said if workers were at risk, so too were passengers.
"For any other trains there is no difficulty with us operating them," Mr Doogan said.QR has been sought for comment.