Width restriction are a self-enforcing means of restricting road access for large vehicles. Posts or bollards are placed in the road about 7 feet (2.1 metres) apart so that vehicles wider than this cannot pass between them. As an alternative route must be available for large vehicles such as refuse collection vehicles, their use in residential areas may be limited.
Many residents mistakenly ask for width restrictions to be introduced as a means of slowing traffic. Width restrictions do not, and are not intended to, reduce traffic speed.
Sometimes a gate is provided for use by fire engines and other emergency vehicles. The gate is kept locked but emergency vehicles carry the key.