SIPTU has called for the introduction of a social intervention unit to work alongside the public transport police.
The Government has announced that recruitment for a dedicated transport police force could begin before the end of 2026.
Speaking on RTÉ's Drivetime, SIPTU’s Transport Sector Organiser John Murphy said that the additional unit would deal with instances that were not criminal behaviour.
"They would be there to deal with what might be portrayed as antisocial behaviour, but it's not criminal as such," he said.
"It would be the likes of people suffering from addictions, homeless people, people with mental difficulties who are utilising public transport, but are putting people who may have taken the decision to travel on public transport off."
Mr Murphy said that the proposed public transport police would not be a replacement for An Garda Síochána.
"It's not a replacement for An Garda Síochána, and An Garda Síochána would still have a role in the overall policing of our society.
"But they (public transport police) would have powers of arrest and detention, which the private security that are operating in public transport now don't have", he added.
Mr Murphy said that the new force would be rolled out in bigger cities at first, with a view to a country-wide rollout.
"We think it should initially be based in the primary cities, the likes of Dublin, Cork, Limerick, potentially Galway, Waterford, where there is the bigger population and more public transport services, but it should have a country wide remit as well," he said.
Mr Murphy said that new measures would be cost-effective compared to what is currently being spent on security on public transport.
"We believe that a force of around 100, depending on wages and terms and conditions that apply, could actually be cost-neutral," he said.
He added that between 2018 and 2022, with private security across Transdev, the Luas operator, Irish Rail and Bus Éireann, there is a cost of approximately €52 million.
"That's paid out by the operators and by the National Transport Authority, on behalf of the Department of Transport," he said.
