The Cabinet will today discuss lowering the legal alcohol limits for train and tram drivers.
It is part of a proposal which will also allow rail drivers to be tested for drugs.
The current legal limit for professional drivers is 20mg of alcohol per 100ml of blood.
However, the law has not been updated for rail drivers in recent years, which means the threshold for them is four times higher.
Transport Minister Shane Ross is bringing proposals to Cabinet this morning which will change that and bring the limits into line with other full-time drivers.
The Railway Safety Amendment Bill will also allow rail drivers to be tested for drugs - similar to the system introduced last year to test motorists.