The type, size and shape of a turning place in a road
depends on the road use in that particular area. It also has
to be suitable for the needs of the road users and must meet
town planning requirements. It is difficult to make
recommendations for a correct choice of road turning place
which is valid in all cases.
The interests of the fire and refuse collection services
have to be taken into account in deciding on road turning
places. Many authorities refuse to service areas with deadend
roads or lanes, where refuse collection lorries can turn
only by manoeuvring backwards and forwards or must
reverse quite a long distance.
Road turning places can be designed as hammerheads
@-@' turning circles or loops -> @-@. The hammerhead type
turning place calls for backwards and forwards manoeuvring.
Turning circles and loops are preferable, as motor vehicles
can drive straight round them without having to stop.
To facilitate steering, road turning places should be
arranged asymmetrically on the left, or on the right in the
case of those countries like the UK which drive on the lefthand
side of the road -+ @-@. Adequate clear areas should
be left along the outside edges of the turning areas to
safeguard fixed obstructions from the overhang of turning
vehicles. In the case of turning loops, the central area to be
driven around can be planted -. @.
Hammerhead turning places are really only suitable for
cars. They are not required for carriageways over 6 m wide,
if garage forecourts or footpath crossings are available for
turning purposes.