Irish Rail's being criticised over it's lack of enforcement of public health guidelines.
It follows an incident of overcrowding on one of its services over the weekend.
On Sunday a photo emerged on social media showing one of Irish Rail's Galway to Dublin services with crowds in a carriage.
Many people were sitting on the floor, and not observing social distancing.
Rail users Ireland spokesperson Mark Gleeson says it's not the first time he's heard of such incidents on trains since new face covering laws were introduced.
Irish Rail has since apologised for Sunday's overcrowding incident.
But spokesperson Barry Kenny says the new rules on face coverings means social distancing can be reduced.
He says capacity on the Galway service and others around the country will however be revised going forward to ensure similar incidents are not repeated.
50% of the seats are marked off so that people can socially distance - yet every carriage corridor looks like this. Impossible to get to the toilet without being on top of one & other. I don’t mean to sound negative - but this is not right @IrishRail @MichealMartinTD pic.twitter.com/hGhP43Fj5l
— Holly Carpenter (@Holly0910) July 19, 2020