Transdev is to introduce signs on Luas platforms after what are described as 'Trap and Drag' incidents.
It is in response to a report by the Rail Accident Investigation Unit (RAIU).
The RAIU reports that two 'Trap and Drag' incidents have happened involving Luas trams recently.
Mark Gleeson from Rail Users Ireland explained: "It's where a passenger boarding a tram or train becomes trapped when the door closes. They find themselves outside the vehicle as the tram or train moves off and are unable to extract themselves.
"It's quite a rare occurrence, but doors are automatically designed to reopen if they are obstructed, provided the obstruction is greater than 10mm in width."
This happened to a man last March at Heuston, his hand got trapped in the doors as they were closing.
As normal, the tram began to move, dragging the helpless man along with it.
However, two security staff spotted what was happening and the tram stopped five seconds later.
Kevin Carter from the Dublin Commuter Coalition said: "Myself and the other members of the Dublin Commuter Coalition are extremely concerned to see an increase in these types of events where people's hands, clothing and other parts of their body are getting trapped in Luas doors.
"We are concerned that as the Luas becomes more and more crowded, that these types of events will become more common, so we would like to see an increase in driver awareness before they set off."
The RAIU has made a number of safety recommendations, including more training for drivers and security staff, and a requirement for drivers to carry out a thorough check (using CCTV and mirrors) before moving off.