Semi-trucks, also called 18-wheelers and tractor-trailers, have four blind spots — one behind the trailer, one along each side of the trailer, and one below the cab of the truck. Your vehicle can disappear from the truck driver’s view in these blind spots.

Truck accidents have many different causes. You cannot do much to avoid accidents caused by speeding, drowsy driving, and improper loading. But you can avoid a blind spot accident.

Here is a guide to the four blind spots on an 18-wheeler and how to avoid them.

Blind Spots on an 18-Wheeler

The blind spots on an 18-wheeler come from its size and configuration. The driver sits in front of the load. The driver cannot see to the sides or behind the trailer except when using mirrors. 

Moreover, because of the position of the driver in the cab, the truck obstructs the driver’s view in front of the truck and the passenger’s side of the truck.

Side Blind Spots

18-wheelers are big. Texas does not limit the overall length of an 18-wheeler, but it does limit the length of the trailer to 59 feet. The distance from the front of the trailer to the front of the tractor averages 11 feet. This puts the average length of an 18-wheeler at 70 feet.

Driver’s Side Blind Spot

The blind spot on the driver’s side is smaller than the blind spot on the passenger’s side of the truck. The driver’s position allows the driver to see cars to the left side of the truck. But because of the size of the side window, the truck and trailer block most of the driver’s view behind the driver.

According to the Federal Motor Carrier Safety Administration, the blind spot runs about halfway down the length of the trailer. The driver can see the back half of the left side of the trailer through the driver’s side mirrors.

Passenger’s Side Blind Spot

The blind spot on the passenger’s side is massive. Because of the driver’s position on the left side of the cab, the driver can see only a small area out of the right window and a small area near the back of the trailer through the right side mirrors. As a result, the blind spot runs almost the entire length of the trailer on the right side.

The width of the blind spot is also massive. The driver probably cannot see you in either of the adjacent two lanes to the right of the truck.

Rear Blind Spot

18-wheelers have no rearview mirror. This might seem obvious, but many motorists forget that truck drivers cannot see behind the trailer. The side mirrors allow the driver a fairly good view of the rear corners of the trailer to both the right and left sides. But the trailer will block the driver’s view directly to the rear.

Front Blind Spot

Most motorists do not realize that an 18-wheeler has a front blind spot. But truck drivers cannot see directly in front of trucks that have their engine in front of the cab.

Texas sets the maximum height of a tractor to 14 feet. This means the truck driver’s head is about nine to ten feet above the ground. When the engine sits in front of the cab, the engine can block the driver’s vision up to 20 feet in front of the truck.

Driving Safely Near an 18-Wheeler

Knowing the location of the blind spots can help you reduce the risk of a blind spot accident. Some ways to stay out of a truck driver’s blind spots include:

  • Do not pass on the right of an 18-wheeler
  • Pass quickly on the left rather than riding alongside the 18-wheeler
  • After passing, leave at least 20 feet between you and the truck behind you
  • Do not tailgate 18-wheelers

Truck accidents can cause catastrophic injuries due to the sheer size and weight of the truck. Avoiding blind spots can save you from one of these devastating accidents.