Proposed changes would bring the limits in line with other full-time drivers
The Cabinet will today discuss lowering the legal alcohol limits for train and tram drivers.
It's part of a proposal which 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.
It comes as the Dáil is this week set to continue debate on the Road Traffic (Amendment) Bill 2017, amid opposition from several TDs from predominantly rural areas.
If passed, the drink-driving bill would see an automatic driving ban for first-time offenders detected at the lowest limit.
Currently drivers caught with alcohol concentrations of between 50mg and 80mg are facing a fine and penalty points, but no ban – provided it is their first offence.
Reporting by Paul Quinn and Stephen McNeice