By Amy Terrone
Have you ever driven by a weigh station on the side of the highway and wondered what happens to all those trucks that enter that parallel roadway?
And why do some trucks get to whiz by, while others crawl into the station?

I learned the answer to these questions recently when I joined NTSB highway investigators for a tour of one of Idaho’s busiest weigh stations. This visit was sponsored by the Idaho State Police (ISP) commercial motor vehicle enforcement team, which works closely with the Idaho Transportation Department, the lead agency for size and weight and encompasses the Port of Entry Inspectors and weigh stations. The ISP is the lead agency for safety; they inspect commercial trucks for safety violations and put them out of service if they aren’t complying with state and federal regulations.
Several NTSB Highway Safety Investigators and I were attending the Commercial Vehicle Safety Alliance (CVSA) annual conference in Boise, Idaho, last week when the ISP presented us with an opportunity to view the live operations at one of their weigh stations. (The outgoing CVSA president is an ISP major.)
The CVSA conference brings together commercial vehicle truck inspectors (mainly law enforcement), truck and motorcoach fleet owners, regulatory agencies, and other commercial motor vehicle safety advocates around the nation to discuss the latest safety innovations, regulatory requirements, and inspection tactics for commercial motor vehicles.
It turns out that trucks which have been pre-screened and which have a current good safety record, similar to the TSA pre-check for airline passengers, can skip specific roadside weigh stations. Idaho uses a bypass system called NORPASS. With about 30 commercial motor vehicle enforcement officers covering the whole state of Idaho, the goal is not to spend time focusing on the truck drivers/operators who are making the commitment to operate safely and follow regulations.
Those drivers who don’t participate in NORPASS must come in to be…yes, weighed. If the loaded truck weighs more than 80,000 pounds, give or take, then the driver may be asked to pull over and unload.
Why do we care about weight? Because too much weight can tear up the roadway, creating a safety hazard for all drivers. Plus — and the NTSB has seen this in our investigations — overweight trucks can cause additional damage if involved in crashes.
But other information can come out of these weigh station stops.
The weigh station manager showed us how information pops up on their screens as trucks come through that indicates the trucks weight, height, safety score and paper credentials, i.e. registration, taxes, and any out-of-service violations or suspensions.
ISP commercial motor vehicle officers onsite may also conduct a random inspection. If such an inspection uncovers serious violations, then the truck, the driver, or both may be placed “out of service” — meaning they can’t continue to operate until the unsafe condition has been corrected.
What happens if a truck without the NORPASS transponder runs the station? Commercial motor vehicle enforcement officers chase them down.

I was impressed by how smoothly the operation ran at the Boise weigh station. There was a separate lane for “regulars” so to speak who traverse the station daily or at least multiple times weekly. A person sits behind the window and watches every truck going through, carefully noting the license plate, VIN, and other identifying vehicle information.
With “Strengthening Commercial Trucking Safety” on the NTSB’s Most Wanted List of safety critical improvements, it was important for NTSB to be at the CVSA conference and tour sites such as this roadside weigh station. More than 4,000 people die each year as a result of truck crashes, and truck crashes have been on the rise. Our visit to the ISP weigh station gave us a first-hand look at the work being done to combat this truck safety problem and how information obtained from them can provide us with valuable information in our crash investigations.
Like many of us on the roads, I didn’t know all that was happening inside these non-descript buildings on the side of the road. The men and women who staff them are our eyes and ears on the roads – looking for bad trucks and bad drivers. And, ultimately, the work they do is a critical component of the highway safety process that will help reduce crashes, along with injuries and fatalities on our roadways.
Amy Terrone is a Writer-Editor in the NTSB Office of Highway Safety.