I assume the Deputy is referring to an incident which took place on 6 April 2005.
The Interim Railway Safety Commission has already been in contact with Iarnród Éireann about this incident and will monitor closely the company's internal inquiry.
If this monitoring reveals issues of importance to railway safety, the Interim Railway Safety Commission will take appropriate action.
In the meantime, pending the outcome of its internal inquiries, I understand that Iarnród Éireann has taken the railcar sets in question out of service and has locked the doors between similar railcar sets. This will prevent any accidental falls from a divided train and ensure that passenger safety is assured in the unlikely event of a further such train divide.