|Roads that are part of the National Network for trucks in the United States.|
|Used on these elements|
|Status: in use|
|Tools for this tag|
This tag indicates that a road is part of the National Network of truck routes in the United States. As such, it complements hgv=designated as one of several specialized alternatives to designation=* commonly used in the United States.
The property tag hgv:national_network=* was used by two large imports in 2010 and 2012 to designate roads in the USA as members of the National Truck Network, major roads, mainly motorways and highway=trunk, designated for long-distance use by heavy goods vehicles (HGVs), known as "Trucks" in American English. hgv:state_network=* was introduced in similar fashion for extensions to the National Network based on alternative regulations for trucks in state law.
The National Network (NN) includes almost all of the Interstate Highway System and other, specified non-Interstate highways. The network comprises more than 200,000 miles (320,000 km) of highways
The routes have been designated on the basis of their general adherence to the following criteria, however, not all highways with the following criteria are part of the National Network:
- The route is a geometrically typical component of the Federal-Aid Primary System, serving to link principal cities and densely developed portions of the States.
- The route is a high volume route utilized extensively by large vehicles for interstate commerce.
- The route does not have any restrictions precluding use by conventional combination vehicles.
- The route has adequate geometrics to support safe operations, considering sight distance, severity and length of grades, pavement width, horizontal curvature, shoulder width, bridge clearances and load limits, traffic volumes and vehicle mix, and intersection geometry.
- The route consists of lanes designed to be a width of 12 feet (3.7 m) or more or is otherwise consistent with highway safety.
- The route does not have any unusual characteristics causing current or anticipated safety problems.
Note that the term "truck route" does not refer to a route in a strict sense. The National Network is not broken down into individual routes with their own identities; it is essentially a collection of interconnected road segments with a consistent designation.
Some states, such as California and New York, distinguish multiple road networks for use by trucks that meet certain criteria. An identical truck may be allowed on one truck route but not another, making it important to distinguish the National Network and its subtypes with a more specific tag than hgv=designated.
How to map
In California, trucks allowed to use the National Network are known as "green" or "STAA" trucks, as opposed to "black" or "California Legal" trucks. hgv:national_network=terminal_access is used for a Terminal Access road that can carry STAA trucks and has an adequate turnaround facility at the end, most often providing access for cargo pick-up or delivery. STAA trucks are also allowed onto Service Access roads but only for one mile in order to obtain food, fuel, lodging, or repair.  As of 2021, no Service Access roads have been tagged. hgv:state_network=* is used on roads that only allow California Legal trucks.