As with many features of the road, most people don’t give much thought to the guardrails they often see along their commutes and travels. Indeed, guardrails weren’t designed to be attention-grabbers, but rather silent, protective structures that help drivers when necessary. But how safe are roadside guardrails, anyway? To shed more light on guardrails, let’s go over their function and how they accomplish it .

What They Do

Guardrails are installed along parts of the road where a barrier is necessary to stop vehicles from falling down steep drops or crashing into rigid structures. In less serious situations, guardrails can redirect cars back onto the road when they swerve to the side. In more severe scenarios, guardrails can slow vehicles to a halt while decreasing the force of impact they might have experienced had they crashed into another obstacle instead.

How They Work

Similar to the fronts of cars, guardrails are made to crumple and have some give so that they can perform their purpose without injuring the people inside the vehicles. If they were made to be completely unmoving, guardrails would more likely spear through cars than cushion them.

This works whether they’re hit from the side along their face or straight on at their starting end, which is called the terminal. The guardrail bends when a car makes contact with it in order to redirect the automobile. The terminal slides backwards and curves away from the car to slow it down without reciprocating the entirety of the force with which it was hit. As this occurs, the car safely moves to the side of the road.


Guardrails undergo testing before they’re installed. Cars are intentionally crashed onto the guardrails’ faces and terminals at varying angles to ensure the guardrail acts as it should. However, the vehicles in these tests are usually moving at around sixty miles per hour—any speed above this threshold can hamper the effectiveness of the guardrail. When people are driving in areas with guardrails, they need to remember that adherence to the posted speed limit is still absolutely crucial, as it is on any road.

If you’re looking for guardrail contractors who can install trustworthy, safe roadside guardrail systems for the roads in your area, call Durham Fence & Guardrail. We place strict importance on our timeliness, our ability to stay within budget, and the upkeep of our guardrails’ quality.