Do car scrapping schemes help the environment and increase safety?

A comparative study of three national car scrapping schemes carried out by the International Transport Forum indicates that:

► Car fleet renewal schemes can reduce CO2 emissions and air pollution and can contribute to making roads safer
► But the gains are insufficient to make up for the value of the scrapped cars - in some cases the net losses were large
► Claims of reduced environmental impacts and improved safety should not serve as the main argument for scrapping programmes
► Schemes can be better designed to maximise their environmental safety impacts