Face masks should be compulsory for anyone using public transport, according to the National Bus and Rail Union (NBRU).
Currently using face masks on bus and train services is not mandatory.
Last month the Taoiseach said science is equivocal on the issue.
But Dermot O'Leary, from the NBRU, says the union is recommending to government that face masks on transport become mandatory.
"They should be but what we need to figure out as a society is what stage is that at?
"Is it stage two, three, four or five?
"We are open to having a debate on that and that is part of the issue that we put to the Oireachtas committee on Covid over the weekend and it is a question that needs to be answered.
"At the moment, there is lots of confusion abroad over face masks."