A group representing the nightlife sector says the new regulations around nightclubs will see closures.
Rules around nightclubs and late venues mean anyone going to a venue from Friday needs to have a ticket at least an hour in advance.
Face masks should be worn in all indoor venues at all times by staff and customers - except when customers are dancing, drinking or eating.
Congregation at counters or bars is not permitted and queues must be managed, orderly and socially distant.
Bar service can operate in nightclubs with one-metre social distancing for ordering, paying for or collecting food and drinks.
But consumption of food and drinks is not permitted at counters.
Sunil Sharpe is spokesperson for the Give Us The Night campaign. He told Newstalk Breakfast he is disappointed at the new rules.
"We don't feel lucky to be open because COVID cases are on the rise.
"Quite a few operators did not open last week and are not opening this week either, so let's not push this 'lucky to be open' idea.
"We're unlucky to be walking back into rising COVID cases, and the reality now is that the regulations and restrictions that venues have to operate under will be unsustainable for many.
"The fact that a lot of venues stayed shut last weekend and then this weekend too - which are two of the biggest weekends of this part of the year - says a lot about the rules and restrictions that have been put into place."
'The death of walk ups'
Sunil says the ticketing approach seems to have been a last-minute decision.
"These were last-minute decisions, the guidelines should have been put together in coordination with the department's own health and safety consultants.
"And from what I'm seeing, and I'm guessing anyway, they would not have been behind this ticket-only idea.
"This was just lobbed in at the end; the Culture Department were told that this is the way it has to be".
And he says the changes will mean the death of 'walk ups'.
"There would have been no problem with ticketing, and with some of these measures, if there had of been planning, if there had of been proper engagement between the industry.
"That will kill the walk up, it threatens the very business model that these venues operate under.
"It's key, and it will lead to closures - the longer that this is in place it will lead to closures".
He adds that nightclubs and bars did not get their guidelines in advance.
"The difference on top of that was that this was happening before COVID, we were haemorrhaging venues.
"And now, when we finally did re-open, we didn't even have guidelines provided to us.
"So to be able to respond to that at last minute - I don't think anyone in the industry is refusing to put in these new measures.
"But we need some time to get ready first, and we also need a review, we need a review in a few weeks' time."
