Weigh station

A weigh station is a checkpoint along a highway to inspect vehicular weights and safety compliance criteria.

Many jurisdictions employ the use of portable scales, allowing weigh stations to be set up at any point.

A common reason for setting up portable scales is to monitor trucks during harvest season.

Interior weigh stations are often located at choke points or areas where freight originates or is delivered.

Overweight permits are only issued for loads that cannot be broken down to smaller shipments that fall below the federal weight limit, and if there is no other alternative to moving the cargo by truck.

The first state to implement a weight law was Maine, which set a limit of 18,000 pounds (9 tons; 8,200 kg) in 1918.

"[3] Many states now use electronic bypass systems (or AVI - Automatic Vehicle Identification) to alleviate some of the truck traffic through the weigh station.

The system may consist of equipment at the weigh station itself, as well as a truck mounted transponder or smartphone, usually placed on the inside of the windshield or on the dashboard.

The registration process propagates information such as carrier name, unit number, and elected gross weight to weigh stations.

If the safety information is acceptable, the truck may receive a green light and can continue without entering the weigh station at all.

A 2020 Texas A&M Traffic Institute study commissioned by a trucking safety advocate nonprofit group revealed performance differences between weigh station bypass systems that use transponders, stand-alone hardware devices that uses RFID technology, versus wireless app-based communication technologies that work via a mobile device (smart phone or tablet) in the truck or as part of a truck's on-board telematics.

In Taiwan, weigh stations (Chinese: 地磅站) are located on major highways, especially at all toll booths on freeways.

Advanced signs tell that trucks must enter the weigh stations when the attached lights are flashing, usually when tolls are collected.

The Taiwan Area National Freeway Bureau applies for periodical inspections of truck scales every three months.

[6] Truckers entering a weigh-in-motion scale are advised not to accelerate or decelerate suddenly, or they may be required to be weighed again.

[7] By using sensors embedded in the road surfaces, combined with cameras that can recognize licence plates, vehicles can be weighed without the need to stop.