More than 110 incidents of 'surfing' have been recorded by Luas and Irish Rail in the past four years.
The potentially lethal practice, also known as 'scutting', involves holding on to the side of a train or tram as it moves away from a station.
The activity came to prominence in October when Rebecca Kelly (20) received €550,000 for severe brain injuries she received after falling from a Luas carriage.
Ms Kelly - who admitted she had done a "silly thing" - had to be pulled out of the way of an oncoming tram when she fell on to the tracks.
Figures released under the Freedom of Information Act show there have been 35 cases of tram surfing in the past four years.
The incidents are split almost evenly between the Red Line, which links the Point with Tallaght and Saggart, and the Green Line, which runs through Dublin's southside.
Dervla Brophy, of Transdev - which operates both Luas lines - said: "Surfing can be fatal. All staff are trained to be vigilant, observe and report. The public have also reported cases.
"Any activity, or concerns, that are reported will result in the tram being stopped, and security or gardai being called.
"It's important to stress just how dangerous 'surfing' is - the risk of serious injury is very high."
Transdev delivers school talks on the dangers of 'surfing' and the potential consequences are made clear on school and gardai community forums.
"We show CCTV of various 'surfing' incidents on the lines," said Ms Brophy.
"The purpose is to ensure that parents know where their kids are - and that if children are on the lines, they know how dangerous their 'playground' might be."
Irish Rail said there had been 87 incidents of train surfing since 2016, 75 of which were on DART services.
Of incidents recorded during the past three years, 12 were on the Northern commuter route, which connects Dublin and Dundalk. Apart from the DART services, no other trains were affected.
Irish Rail's Barry Kenny said 'surfing' was a "continuing issue".
"On-board staff, station staff and security personnel are vigilant in ensuring we respond with security or garda support when 'surfing' occurs.
"Extra security patrols this year are yielding a reduction in the number of incidents over 2017."
Irish Rail said it had modified the original DART fleet of 76 carriages during refurbishment to make headlight units more difficult to hold on to.
The operator said future fleet orders would have preventative measures incorporated into the design.