The provision of speed ramps is a matter for individual local authorities. Where they are provided, their function is to reduce vehicle speeds, reduce the number and severity of accidents and lessen concerns over road safety. It is possible that some minimal increases in noise and vehicle emissions may occur but these can be minimised with good design. My Department, in conjunction with the Dublin Transportation Office and the Department of Transport, is preparing a traffic management guidelines manual which will, inter alia, deal with speed management and traffic calming.