Dublin's LGV ban came into force this week, with drivers facing a €1,500 (£990) fine and a prison sentence if they enter the city centre without a permit.
From last Monday, trucks with five axles or more entering the city between 7am and 7pm must have a permit. These will be free until May, and €5 per truck thereafter.
The controversial ban, designed to make the city more accessible to other vehicles and pedestrians, is part of a new traffic-management strategy put in place following the opening of the Dublin Port Tunnel in December.
But Jimmy Quinn, vice president of the Irish Road Haulage Association, has criticised the ban: "It is an enormous sledgehammer to crack a very small nut.
"We have no problem with the notion that transit vehicles should not be in the heart of any city," he adds. "But the basic premise is that instead of using double-decker trailers we go back to driving 7.5-tonne rigids. The long-term strategy needs to be re-examined. It's a nonsense to suggest that it's more environmentally friendly to replace larger vehicles with smaller ones."
Quinn adds that the new port tunnel has already taken 6,000 trucks a day off Dublin's streets - but he points out that the closure of Sean Moore Road will force drivers to take longer routes.
The local authority expects an extra 2,000 LGVs to use the M50 every day following the ban however it can be lifted if the road becomes too jammed.
