The Minister for Transport, Mr Brennan, is expected to face questions today about the use of wire fencing in the centre of the country's motorways following a fatal accident on the M1 in Co Louth yesterday.
A man from Northern Ireland died in the accident when the van he was driving lost control, went from the northbound to the southbound carriageway and collided with an articulated truck travelling towards Dublin.
This was the second fatal accident in less than a year on the M1 in Louth.
Mr Brennan is expected to be asked about the use of hedges and wire fences to divide motorways when he opens the final stretch of the M1 between the airport and the Drogheda bypass today.
Yesterday's accident happened just after 10 a.m. about three kilometres south of Dundalk at Whiterath, close to the Castlebellingham interchange on the Dunleer-Dundalk section of the motorway.
Last August, a few miles south of yesterday's accident, three young people from Dundalk died when their car crossed the central reservation.
They were Gerard McLoughlin (22), Elaine McGeough (21) and Celine McArdle (21). They were travelling towards Dublin when the car went out of control, ploughed through the so-called "chicken wire" and bushes dividing the carriageways and into the path of an oncoming van.
At the time gardaí and emergency personnel questioned the role of the chicken wire used to divide the central reservation, and whether EU standard crash barriers could have saved lives.
Following a similar accident on the M50 in Dublin in 2001 the National Roads Authority revised its policy on the use of crash barriers. Anywhere the central median is 15 metres or less, barriers will be installed as part of a "retro-fit" programme on all motorways and dual carriageways.
However, the fitting of the barriers on the M1 will be the responsibility of the successful tender in the contract for the public-private partnership for the Dundalk western bypass.
The successful consortiums will operate the controversial toll booths on the Drogheda bypass, build the western bypass and have to fit the crash barriers on the existing and new sections of the motorway from Balbriggan northwards.
The crash barriers have been installed on the Drogheda bypass and on the 16km section of motorway being opened this morning, wherever the central divide is less than 15 metres.
Mr Michael Egan, head of corporate affairs with the NRA, said: "We hope the revised policy will further contribute to enhancing road safety, but we cannot guarantee that there won't be fatalities involving accidents arising from collision with crash barriers."
There are two consortiums on the final list for the contract to be awarded by Christmas.