THE controversial plan to introduce a maximum speed limit of 30kph across the city centre from today has been endorsed by a leading academic.


Dr Enda Murphy, of the school of planning and environmental policy at UCD, claimed that Dublin City Council's new speed limit by-laws will have the positive effect of reducing noise levels in the capital.


He said: "Generally, there is a direct correlation between reductions in speed and reductions in noise levels within cities."


Murphy, who has conducted a number of extensive studies in this area, believes that "there should be a positive reduction in noise levels in Dublin with the introduction of the new speed limits."


He also contends that even though people "may not be totally aware of the reduction in noise, it may reduce annoyance levels. For example, people get angry when a car races past quite quickly.


"Implementing the speed decrease is likely to have a slight impact on reducing noise pollution, but the real benefit is likely to be in making the city more attractive for cyclists."


The reduced limit, app­roved by councillors last October, comes into effect today. It applies from Bolton Street on the northside to Kevin Street Lower and St Stephen's Green on the southside. O'Connell Street, Dame Street, and the north and south quays are included in the plan.


The city council claims that the move will result in smoother traffic flow and encourage people to cycle or walk so it will ease traffic congestion. It also cites statistics showing that 47% of fatalities and 24% of injuries in accidents on city-centre roads involve pedestrians.


The plan has been criticised by the AA and the gardaí. A senior garda working for the traffic corps in Dublin city centre said that elements of the new speed limit plans "do not make sense".


Conor Faughnan, director of policy at the AA, has brandished the proposal "a significant mistake".