In this section, we’ll take a more comprehensive look at how policy and enforcement can be initiated to “push” urban freight transport actors towards more sustainable technology and activity. The measures that fall under access restrictions are quite varied. We’ll introduce some briefly here.

Time Access Restrictions

Time access restrictions, also known as time-windows, restrict trucks from entering a certain area within a certain time. The time-window area is often the city center or even a smaller part, the pedestrian area within the city center. Sometimes time-window restrictions allow delivery trucks access for a certain time period to areas where normally no motorized vehicles are allowed, such as pedestrian areas.

Vehicle Restrictions

Vehicle restrictions prevent vehicles that have certain characteristics from entering a certain area (e.g., city center, specific streets). Vehicle restrictions can apply to various vehicle characteristics, such as length, width, height, axle pressure, and weight. A specific vehicle restriction, the amount of emissions emitted by the vehicle’s engine, is discussed in another restriction, the low emission zone.

Low Emission Zones/Environmental Zones (Engine Restrictions)

Low emission zones or environmental zones restrict polluting vehicles from entering a defined area. This can be considered an advanced type of vehicle restrictions. Usually the vehicle receives a special sticker that marks it as qualified to enter the zone.

Vehicle Load Factor Controls

A vehicle’s load factor should ensure that only fully (or at least to a certain extent) loaded vehicles enter an area, such as the city center. Urban freight vehicles have, on average, a low load factor (due to several reasons). Enforcement of such controls are difficult.

Road Pricing

Road pricing is an access regulation that usually affects not only freight transport, but all transport, although the prices might discriminate between passenger and freight transportation. Depending on the primary function of the road pricing, the price may increase for different times in a day or depending on how “clean” the vehicle is. Note that this not a restriction per se,but falls more under traffic management schemes.

Parking and Unloading Restrictions

Finally, parking and unloading restrictions regulate the locations in an area where large vehicles are allowed to park in order to unload deliveries or load pickups. Parking restrictions on other road users might also be used to facilitate the loading and unloading activities of freight vehicles on a particular street at a particular time.