What is a Truck Entry Warning System?

This fully automated system provides an advance warning when slow-moving construction vehicles are about to merge into traffic. Advanced warnings allow motorists to be alert and adjust their driving accordingly, reducing the risk of crashes, due to high-speed differentials.

In 2021, 323 commercial motor vehicle crashes were recorded. The Truck Entry System helps make roads safer for drivers and construction workers.

Truck Entry system
Message sign truck entering

How does a Truck Entry Warning System Work?

Traffic sensors detect when a truck is leaving a work zone and heading for the roadway.

This information is transmitted to a portable changeable message sign (PCMS) or a static sign and conditional (“when flashing”) beacons. The warnings are displayed in real-time to motorists downstream, alerting them of a truck entering traffic ahead.  



Certain roadwork zones, because of their configuration or location, need a truck access control system from restricted construction areas to ensure the safety of workers and drivers alike.

For example:

  • Construction projects with concrete barriers and entry/exit points for construction vehicles
  • Construction projects with blind entrances for construction vehicles
  • Construction projects that do not have a long enough entrance ramp for construction vehicles to reach the work zone speed limit

Why Use a Truck Entry Warning System?

The Federal Motor Carrier Safety Administration (FMCSA) conducted a study on large trucks and vehicle crash causation. It found that 32% of those crashes were caused by trucks running out of the travel lane, either into another lane or off the road. Many of these crashes resulted in death and serious injuries. Ver-Mac’s Truck Entry System helps lessen these risks.

Improved Motorist and Worker Safety

    When trucks or slow-moving vehicles merge into traffic, they can collide with motorists who are travelling at higher speeds and may not have sufficient time to slow down. Ver-Mac’s Truck Entry System warns drivers in advance and helps lessen the risk of collisions with slow construction vehicles.

Enhanced Mobility

    Motorists can slow down or switch lanes out of the work zone access lane after receiving an advance warning, so traffic keeps flowing smoothly.

Valuable Information

Valuable Information

    Historically, these have been isolated systems, but with the advancement of connected work zones, these warning devices should be connected to the cloud-based system manager (JamLogic) to provide a history of activations, system health monitoring and optional system alerts.


  • Fully automated system
  • Radio communication between sensors and the warning device 
  • Remote management via JamLogic® is highly recommended to provide data logging, system status/health and activation history.

Frequently Asked Questions About Truck Entry Systems

How accurate are truck entry systems in detecting off-road trucks entering the work zone?

The truck entry system sensors are very accurate, with presence sensors that can detect a defined construction egress area.

The overall area should be wider than two lanes and the sensor should be placed where vehicles wait before entering. Too wide or large an area could result in no detections, thus no warnings, so it is essential that the egress area is well defined.