What are weigh stations for and why are they needed?

Estimated reading time: 3 minutes 

Weigh stations can be found all over the nation’s highways, but if you are new to the transportation industry, you might not know exactly what they’re for. 

Keep reading to find out how weigh stations keep roads and drivers safe and what to expect when stopping at one.  

What is a weigh station? 

Truck weigh stations are checkpoints located along highways where officials check the weight of commercial vehicles over 10,000 pounds. Weigh stations use large scales to make sure vehicles are following Department of Transportation (DOT) regulations. 

What are weigh stations for? 

The purpose of weigh stations is to prevent roads and bridges from being damaged by overweight commercial vehicles. Overweight vehicles cause significant, costly damage compared to regular passenger vehicles, so the government uses these stations to limit their impact.  

Weigh stations also help ensure safety for all drivers on the road by checking that vehicles are well maintained and not at risk of breaking down.  

Some of the safety risks associated with operating an overweight vehicle include: 

• Tire blowouts.
• Longer braking times.
• More difficulty controlling the truck.
• Increased chance of a rollover.

Do semi-trucks have to stop at every weigh station? 

Yes, commercial vehicles over 10,000 pounds must stop at any open weigh stations. If a driver does not stop at an open weigh station, they could be pulled over and fined. 

Why do some trucks not stop at weigh stations, then? Because some drivers, typically with good driving records, have pre-approved passes that allow them to legally skip weigh stations. 

Where are weigh stations located? 

Weigh stations are found just off the highway, often near state borders. Weighs stations at borders, called “ports of entry,” are important because each state has its own vehicle weight regulations.  

Drivers should account for any weigh station stops by looking ahead during their pre-trip planning.

What happens at a weigh station? 

At a weigh station, drivers either roll over a weigh-in-motion scale or stop on a traditional scale to be assessed. This is typically done by a highway patrol officer or an official from the DOT or the Department of Motor Vehicles (DMV).  

Three of the potential weight violations that can be found are: 

• A gross weight of over
• A single-axle weight of over
• A tandem-axle weight of over

If a vehicle is found overweight, consequences include fines, a delay of service and the potential impact to the driver's Compliance, Safety and Accountability score.  

Weigh stations don’t just check the weight of the vehicle, however. On occasion, the officials at a station will conduct a more general inspection of the vehicle.  

There are six levels of inspection that can be performed at a weigh station: 

Level one 

Level one inspections, called “North American Standard Inspections,” are the most thorough level of inspection, since the vehicle and driver are both assessed. In the inspection, drivers have to provide all the necessary documentation (CDL, time logs, etc.) and get evaluated for alcohol and drug use.  

Then, the inspector will conduct a 37-step examination of the vehicle. Some of the focuses of the inspection are: 

• Brake systems. 
• Cargo securement. 
• Coupling devices. 
• Driveline and driveshaft components. 
• Driver’s seat. 
• Exhaust systems. 
• Frames. 
• Fuel systems. 
• Lighting devices. 
• Steering mechanisms. 
• Suspensions. 
• Tires. 
• Van and open-top trailer bodies. 
• Wheels, rims and hubs. 
• Windshield wipers.

Level two 

Level two inspections, called “walk-arounds,” are nearly the same as level one inspections. The only difference is that the inspector does not go under the vehicle, which means the suspension and frame are not included in the inspection.  

Level three 

Level three inspections assess only a driver’s records and credentials. Besides being checked for seat belt and alcohol and drug usage, drivers must provide their: 

• CDL.
• Medical Examiner’s Certificate.
• Skill Performance Evaluation (SPE) Certificate.
• Hours of Service (HOS) logs.
• Record of Duty Status (RODS).
• Carrier identification and status.

Level four 

Level four inspections focus only on a specific aspect of the vehicle, chosen annually by the DOT. This type of examination is typically used to keep an eye on common violations and trends. 

Level five 

Level five inspections assess only the vehicle. This type of inspection is most common at weigh stations following an accident or arrest.  

Level six 

Level six inspections are for vehicles carrying radioactive materials. This level contains all the elements of a level one inspection but with an extra focus on radiological checking.