Weigh station
Encyclopedia
Truck
A truck or lorry is a motor vehicle designed to transport cargo. Trucks vary greatly in size, power, and configuration, with the smallest being mechanically similar to an automobile...
s and commercial vehicle
Commercial vehicle
A commercial vehicle is a type of motor vehicle that may be used for transporting goods or passengers. The European Union defines "commercial motor vehicle" as any motorised road vehicle, which by its type of construction and equipment is designed for, and capable of transporting, whether for...
s are subject to the inspection.
Weigh stations are equipped with truck scale
Truck scale
Truck scales or weigh bridges are large scales, usually mounted permanently on a concrete foundation, that are used to weigh entire vehicles and their contents. By weighing the vehicle both empty and when loaded, the load carried by the vehicle can be calculated...
s, some of which are Weigh in motion
Weigh in motion
Weigh-in-motion or Weighing in Motion devices are designed to capture and record axle weights and gross vehicle weights as vehicles drive over a measurement site...
and permit the trucks to continue moving while being weighed, while older scales require the trucks to stop. There are a variety of scales employed from single axle scales to multi-axle sets. Signal lights indicate if the driver should pull over for additional inspection or if they are allowed to return to the highway.
All jurisdictions employ the use of portable scales, allowing weigh stations to be set up at any point. Portable scales allow states to set up temporary scales for situations such as seasonal check points, temporary checkpoints on isolated roads often used by trucks, and help prevent drivers from avoiding scales at fixed locations. Portable scales may be set up at purpose built locations that are not normally manned. A common reason for setting up portable scales is to monitor trucks during harvest season.
United States
Weigh stations were primarily created to collect road use taxes before IFTA
International Fuel Tax Agreement
The International Fuel Tax Agreement is an agreement between the lower 48 states of the United States and the Canadian provinces, to simplify the reporting of fuel use by motor carriers that operate in more than one jurisdiction. Alaska, Hawaii, and the Canadian territories do not participate...
created an integrated system of doing so. While taxes can still be paid at weigh stations, their primary function is now enforcement of tax and safety regulations. These include: to check freight carrier compliance with fuel tax
Fuel tax
A fuel tax is an excise tax imposed on the sale of fuel. In most countries the fuel tax is imposed on fuels which are intended for transportation...
laws; to check weight restrictions; to check equipment safety; to check compliance with Hours of Service Regulations. Weigh stations are regulated by individual state governments and therefore have vastly different requirements from state to state. They are typically operated by the state's Department of Transportation
Department of Transportation
The Department of Transportation is the most common name for a government agency in North America devoted to transportation. The largest is the United States Department of Transportation, which oversees interstate travel. All U.S. states, Canadian provinces, and many local agencies also have...
(DOT) or Department of Motor Vehicles
Department of Motor Vehicles
In the United States of America, a Department of Motor Vehicles is a state-level government agency that administers vehicle registration and driver licensing. Similar departments exist in Canada...
(DMV) in conjunction with the state highway patrol
Highway patrol
A highway patrol is either a police unit created primarily for the purpose of overseeing and enforcing traffic safety compliance on roads and highways, or a detail within an existing local or regional police agency that is primarily concerned with such duties.Duties of highway patrols or traffic...
or state police
State police
State police are a type of sub-national territorial police force, particularly in Australia and the United States. Some other countries have analogous police forces, such as the provincial police in some Canadian provinces, while in other places, the same responsibilities are held by national...
, thus enabling enforcement of applicable laws. The federal maximum weight is set at 80,000 pounds. Trucks exceeding the federal weight limit can still operate on the country's highways with an overweight permit, but such permits are only issued before the scheduled trip and expire at the end of the trip. Overweight permits are only issued for loads that cannot be broken down to smaller shipments that fall below the federal weight limit, and there is no other alternative to moving the cargo by truck. Permitted oversize trucks are often required to coordinate with the Departments of Transportation and law enforcement agencies of the transited states before the trip begins, as most states require oversize trucks to be escorted
Escort vehicle
An escort vehicle, also called a pilot vehicle in most areas, is an automobile used to escort trucks with large loads, convoys of large vehicles, guide motorists through construction sites, and assist aircraft in taxiing from the runway to the tarmac at many airports...
. Many states have weigh in motion
Weigh in motion
Weigh-in-motion or Weighing in Motion devices are designed to capture and record axle weights and gross vehicle weights as vehicles drive over a measurement site...
technology that allow a continuous flow of truck weighing.
Many states also check freight paperwork, vehicle paperwork, and logbooks to ensure that fuel taxes have been paid and that truck drivers are obeying the Hours of Service
Hours of service
The hours of service are regulations issued by the Federal Motor Carrier Safety Administration governing the working hours of anyone operating a commercial motor vehicle in the United States for the purpose of "interstate commerce"— moving commercial goods from one U.S. state to another...
(a federal requirement). Also the truck and driver may have to undergo a DOT inspection as most states perform the bulk of their DOT inspections at their weigh stations. In some cases, if a truck is found to be overweight, the vehicle is ordered to stop until the situation can be fixed by acquiring an overweight permit. In other cases, the driver may receive an overweight ticket and may or may not be required to offload the extra freight. Offloading the extra freight may not be practical for perishable or hazardous loads. The first state to implement a weight law was Maine
Maine
Maine is a state in the New England region of the northeastern United States, bordered by the Atlantic Ocean to the east and south, New Hampshire to the west, and the Canadian provinces of Quebec to the northwest and New Brunswick to the northeast. Maine is both the northernmost and easternmost...
, which set a limit of 18,000 pounds (8 tons; 8,200 kg) in 1918.
Two types of loads may result in overweight trucks. Divisible and non-divisible. A divisible load is a load which can be easily divided into smaller parts- like products that are shipped on pallets or automobiles or grains, etc. A non-divisible load is a load which is unable to be divided into smaller parts- like a piece of equipment or a steel beam. All states provide permits for non-divisible loads though the truck may have restricted routing. Some states allow tolerances for any over weight truck. Some states have specific allowances for types of loads for which they will allow tolerances. For example, Wyoming allows 2000 pounds for chains, tarps and dunnage
Dunnage
Dunnage is a term with a variety or related meanings. Typically dunnage is inexpensive or waste material used to protect and load securing cargo during transportation...
that accompany a non-divisible load.
Truckers often refer to weigh stations as "chicken coops."
Electronic weigh station bypass
Many states now use electronic bypass systems to alleviate some of the truck traffic through the weigh station. It is best known as PrePassPrePass
PrePass is an intelligent transportation system service that electronically verifies the safety, credentials, and weight of commercial vehicles at participating state highway weigh stations...
, NORPASS
NORPASS
NORPASS is a not-for-profit organization formed from a partnership between state agencies and the North American trucking industry...
, or simply A.V.I. (Automatic Vehicle Identification). The system consists of the equipment at the weigh station itself, as well as a truck mounted transponder, usually placed on the inside of the windshield. These are similar to transponders used for toll collection
Toll road
A toll road is a privately or publicly built road for which a driver pays a toll for use. Structures for which tolls are charged include toll bridges and toll tunnels. Non-toll roads are financed using other sources of revenue, most typically fuel tax or general tax funds...
. Each transponder is directly registered to a specific truck, and contains a unique identification. The registration process propagates information such as carrier name, unit number, and elected gross weight to weigh stations. In addition, the system keeps a basic safety and compliance record for each vehicle. As a truck approaches a weigh station (approximately one mile before), an electronic "reader" on a boom over the freeway reads the information from the truck transponder. At the same time, the truck is usually driving over high-speed electronic scales embedded in the road. The system computes the weight, by axle and gross, and determines if it is within the limits. It also looks at the safety and compliance record
Motor carrier safety rating
The motor carrier safety rating is an evaluation given to an interstate commercial motor carrier by the Federal Motor Carrier Safety Administration ....
on the database. The A display shows the results to the weigh master, including the speed of the vehicle. The weigh master may have the system automatically determine if a truck needs to stop or may override the system. Approximately one-half to one full mile after passing under the "reader", the truck will pass under another boom which has an electronic unit to send the transponder a signal. If the weight and safety information are acceptable the truck may receive a green light and can continue without entering the weigh station at all. A driver may get a red light. On these occasions, the truck must pull into the weigh station for the normal weigh-in procedure. The most common reason a truck is "redlighted" is a weight problem, or a random check. Each time a truck is randomly pulled in, it is noted in the system whether the driver was compliant or not during the check. This affects how often a truck (or different trucks from the same company) are pulled in. For example, a company who is very compliant with the law will probably only have 5% of its trucks "redlighted." On the other hand, a company whose trucks have compliance issues during the random checks will have their information updated accordingly, and might get "redlighted", for example, 30% of the time.
British Columbia
Weigh Stations (aka "Scales") are usually on the right-hand side of the travelled highway, but median scales are appearing (as of 2005) on divided highways, often combined with "weigh-in-motion" technology.A median scale is placed between the opposing lanes of traffic, necessitating heavy vehicles exiting from the left lane (rather than the right) and re-entering traffic from the left, potentially at a lower speed than the normal "free-flow" traffic would expect in the left (often thought of as "fast") lane.
"Weigh-in-motion" technology allows heavy vehicles that do not exceed limits of weight (and size) to pass the scale, thus improving both freight and weigh scale operation efficiency.
Alberta
In Alberta, scales can be on either side of the road, on the median or off-highway. Flashing lights inform drivers as to whether the scale is operational. Occasionally, the lights may be operational in only one direction.Alberta scales are all of the 'weigh-in-motion' type, and vehicles are not required to stop; they merely have to slow to 10 km/h.
Scales which are not operational are often available to drivers as a 'self-weigh' site, where drivers can check their axle loads without enforcement officials being involved.
North West Territories
The government of the North West Territories operates only one scale. It is situated in the townsite of Enterprise, 83 kilometres north of the border with Alberta, and issues permits for vehicles from other jurisdictions as well as weighing vehicles and enforcing hours of service legislation.Taiwan
Since the National Highway No. 1
National Highway No. 1 (Taiwan)
National Highway No. 1 is the first freeway in Taiwan. It begins in Keelung City at the intersection of Ziao 2nd Road and Jhong 4th Road and ends in Kaohsiung City at the intersection of Jhongshan 4th Road and Yugang Road, giving it a total length of 372.8 km...
was built with older designs, all weigh stations have older scales so trucks must stop. Weigh stations along the National Highway No. 3
National Highway No. 3 (Taiwan)
National Highway No. 3 is the second North-South freeway in Taiwan. It begins in Keelung City at Jijin Interchange on the Provincial Highway No. 2 and ends in Linbian, Pingtung on the Provincial Highway No. 17....
have weigh-in-motion scales at 7 central and southern toll stations, but northern stations at Cidu, Shulin, and Longtan
Longtan
-Mainland China:*Longtan Dam , dam in Guangxi*Longtan District , in Jilin, Jilin*Longtan Park , in BeijingSubdistricts *Longtan Subdistrict, Beijing, in Dongcheng District, Beijing...
have traditional scales where trucks must stop.
The Taiwan Area National Freeway Bureau applies for periodical inspections of truck scales every three months. Truckers entering a weigh-in-motion scale are advised not to accelerate or decelerate suddenly, or they may be required to be weighed again.