The police are warning motorists that a reduced speed tolerance of 4 kms an hour will apply from 4pm on Friday.
It will apply until the end of the official Christmas and New Year period on 7 January.
National manager of road policing Superintendent Carey Griffiths says police will be in force over the festive season and will rigourously enforce the reduced speed tolerance.
He says drink-driving, seatbelt wearing, driver distraction and fatigue are also a focus.
He says drivers should also switch off or put away other distractions such as cellphones or smart devices so they are not tempted to use them while driving.