Nightclub and live venue operators have been told that rules requiring tickets to be booked at least one hour in advance will take effect from tomorrow.
At a meeting with Government officials this lunchtime, industry representatives were told there will be no grace period for implementing them, as they had requested.
Guidelines outlining how the new system would work were published last Friday.
Regulations, which legally underpin the guidelines and will contain more detail on how they operate, are expected to be signed by the Minister for Health, Stephen Donnelly, later this evening.
The one-hour advance purchase rule was discussed yesterday following meetings between Government officials and industry representatives, where industry representatives expressed concern at the viability of the measure.
The requirement for a ticket will be determined by whether dancing is taking place, rather than live music as previously envisaged.
The ticket purchase must contain details to allow for robust contact tracing.
The new rules stipulate that customers will not be allowed to congregate at doors and ticket holders only should be allowed in a queue.