Driver Digest: Following the Signs

Reading Time: 3 minutes

Signage is incredibly important on the road, particularly for a truck driver. Signs can alert you to important traffic requirements such as basic stop and go, but can also instruct directions specifically for tractor trailers. Drivers are a key component to the supply chain, and by following signage, products are delivered on time in proper condition.

Staying Within Clearance

truck heigh limit - NFITruck drivers travel through different terrain with a variety of height requirements. Low clearance bridges and overpasses can create a problem for drivers when a planned route does not anticipate these guidelines. According to the U.S. Department of Transportation, 4,209 bridges were struck in 2014, up almost 1,000 from 20101. Trucks can become stuck and severely damaged when striking an overpass in addition to putting the driver and others on the road at risk.

Drivers should be aware of signage indicating the bridge clearance heights and drive with an understanding of the vehicle dimensions. Anticipate the route being taken and plan accordingly to those requirements. A GPS specific to truck driving can provide guidance to those routes that are accessible with a vehicle of that size.

Preparing for Route Changes

Alt. Route Signage - NFIThe best-planned routes can be changed at a moment’s notice when encountering an alternate route indicated by temporary or digital road signage. A change in traffic plan or diverting completely from a road can occur for a variety of reasons. An accident can cause a road to be shut down, resulting in a new temporary traffic pattern. Construction can also require a truck to take an alternate route when the work limits the size of the vehicle permitted through the region2.

Natural disasters and emergencies can shape traffic routes as well. Hurricane Mathew hit the south eastern part of the United States in October 2016, requiring mass evacuation of the coastal regions and an alternate route created on Interstate 95, making the highway one way traffic. Signage and law enforcement communicated the alternate route plans.

Knowing Your Weight

Truck Weight Signage - NFIBridge weight limit signage is in place for the integrity of the bridge. Drivers should note road weight limit signs for their safety and the safety of others. The weight limit is determined by the U.S. Department of Transportation, factoring in the truck’s gross weight and axle weight. The formula factors the amount of weight distributed across the vehicle and the capability of the bridge to support that amount3.

Crossing Borders

Cross Border Trucking - NFIMany drivers transport loads requiring them to cross borders between the U.S. and Canada. Understanding the border crossing requirements and any changes of driving regulations is important to stay safe. When crossing the United States and Canadian border, be prepared with all needed paperwork and follow sign directions for inspection. Knowing your load is important, particularly when transporting vegetables, fruits, plants, and meat products which require additional regulations4.

Understanding local signage is key, particularly with speed limits. While the United States uses miles per hour for speed, Canada utilizes kilometers per hour. Every one kilometer per hour equals .62 miles per hour. Therefore if a sign in Canada read 90 kilometers per hour, this means you should be traveling 55 miles per hour5. Understanding local signage can help a driver continue to operate safely in the area.

Truck drivers should possess an extensive understanding of signage and the requirements for their vehicle across North America. Being prepared for a route and utilizing a proper GPS with truck capabilities can assist a driver in a successful delivery and keeping the customer’s supply chain moving safely.


  1. http://www.ttnews.com/gateclient/premiumstorylogin.aspx?storyid=43188
  2. http://ops.fhwa.dot.gov/publications/ar_handbook/arh.pdf
  3. http://www.ops.fhwa.dot.gov/Freight/publications/brdg_frm_wghts/index.htm