Concerns have been raised about the enforcement of face mask regulations coming into effect on Monday.
It is now compulsory to wear masks on public transport except in specific circumstances.
The decision comes as Ireland’s coronavirus reproductive number increased to one and more cases linked to travel have been imported.
People who refuse to wear a face mask could face fines of up to 2,500 euro and a possible jail sentence of six months.
Drivers can request a passenger to wear a face covering, and can refuse entry on to public transport, or can request the passenger to leave.
Under new rules brought into force on Monday, gardai can be called to enforce if someone fails to wear a face covering.
Circumstances where it is an exception to wear a face mask include those who cannot put one on, wear or remove a face covering because of any physical or mental illness, impairment or disability, those who need to communicate with another person who has difficulties communicating and those who need to remove the face covering to take medication.
Union representatives, however, have raised concerns about the legislation.
National Bus and Rail Union (NBRU) general secretary Dermot O’Leary claimed that no guidance has been issued to transport staff.
“In relation to our members, we will not be policing and we will not be enforcing this legislation,” he told RTE.
“It’s not our role to do it. A bus driver’s job is to drive the bus, not to police the laws of the land.
“What’s missing here is the lack of consultation between us in the front line and our members, and the people who make these laws and the people who make the decisions, particularly the National Transport Authority (NTA).”
The representative body for private bus and coach operators, the Coach Tourism and Transport Council (CTTC), said their members are “disappointed” the Government did not engage with the sector.
CTTC chairman John Halpenny said: “We have no clarity regarding our legal obligations or our potential exposure but instead are appraised of the changes through the media.
“Operating in such a legal lacunae has very real and obvious consequences going by the needless death of a bus driver who was involved in a serious confrontation with passengers over their failure to wear face masks in France in the past few days.
“If the CTTC had been engaged in the decision-making process, all anomalies could have been dealt with and we would have full clarity over the situation.
“With Ireland starting to open up and holidays back on, the Government needs to issue crystal clear messaging and safety advice around getting people back on buses.”
Acting chief medical officer Dr Ronan Glynn said: “When wearing a face covering, ensure your hands are clean before putting on and removing.
“Do not touch the front of the covering, instead apply and remove the covering using the ear loops.
“If you require a number of coverings as you go about your day, store used coverings in a plastic, zip lock bag until you can wash them at 60 degrees.
“It is important to be aware that some members of the public are unable to wear face coverings due to health reasons or age and should not be criticised or judged for this.”
Meanwhile, Sinn Fein has said the wearing of face masks at airports should be mandatory.
There is huge public concern at the arrival into Ireland of visitors from the United States, and the total lack of enforcement of the 14-day mandatory quarantine periodDuncan Smith, Labour
The party’s spokesman for transport Darren O’Rourke called for the Government to produce a “red list” of countries that would enforce 14-day quarantine for people travelling from the area.
He said the US should be included on the “red list”.
Mr O’Rourke added: “You can see the situation has continued to deteriorate and escalate in recent days.
“We believe the response from Government has been completely unsatisfactory. It’s been a one-size-fits-all approach.
“We are in a situation where it’s left to people working in the tourism industry to essentially police the 14-day quarantine.
“We believe that situation is completely unsatisfactory.”
The TD said those travelling from the red-listed countries should be put into a mandatory 14-day isolation.
“I think the US should be on the red list given the Covid-19 profile but we need to discuss what it means to be on the red list,” he added.
Labour transport spokesman Duncan Smith called for the Government to suspend flights from the US and other Covid-19 hotspots until there is mandatory testing at airports for overseas visitors.
Mr Smith said: “There is huge public concern at the arrival into Ireland of visitors from the United States, and the total lack of enforcement of the 14-day mandatory quarantine period.
“The current rules are unworkable and unenforceable, and the public are rightly upset about this. We are the only EU country allowing visitors from the US at the moment.
“The only requirement for visitors is to fill in a passenger locator form, which simply isn’t enough.
“The line from the Government that they will tighten the rules is not sustainable when our current measures are unenforceable and the risk is already here.”