Mae ymchwil yn dangos bod cysylltiad clir rhwng gyrru’n arafach a gostwng nifer gwrthdrawiadau a’r nifer sy’n cael eu hanafu. Ar ffyrdd trefol, am bob 1mya o ostyngiad yn y cyflymder, ceir 6% o ostyngiad yn nifer y gwrthdrawiadau.
Research shows a strong link between lowering speeds and decreasing the number of collisions and people injured. On urban roads with low average speeds, there is average 6% reduction in collisions per 1mph reduction in average speed.