Depending on the way a tractor trailer is designed, its front blind spot can extend as far as 20 feet in front of the truck’s cab. Truckers sit much higher off the road than most other drivers. In addition, many commercial truck cabs have large “noses” in the front that house their engines. As a result, truck drivers are situated at an angle that makes it virtually impossible to see the road immediately in front of them.

Because truckers’ front-end blind spots are so large, they have a duty to avoid tailgating other vehicles. Similarly, other drivers must respect and remember to take the front No Zone into account. Driving too close to the front of a truck — or even worse, cutting off a large truck in traffic— is extremely dangerous. This is because large trucks take about 40% longer to stop than standard passenger cars. The entire front No Zone can extend as much as 10 car lengths from the front of a truck’s cab.

When car drivers cut off large trucks in traffic or linger within front No Zones, they are at considerable risk for rear-end, T-bone, and head-on collisions. According to an analysis from the National Highway Traffic Safety Administration (NHTSA):

• 64% of all fatal crashes between large trucks and other vehicles over a yearlong period involved impacts with the front end of a truck.
• 31% of fatal front-end impact truck crashes during that time were head-on collisions. Another 26% involved the front end of a truck striking the right or left side of another vehicle. 6% involved the front end of a truck colliding with the rear end of another vehicle.

In a separate study, NHTSA found that:

• During a four-year period, 59% of truck accidents that resulted in fatalities or incapacitating injuries involved front-end truck impact points.

Just like the right side of a large truck, a truck’s left side has a substantial blind spot area. Left- side blind spots, however, are slightly smaller than right blind spots because truck drivers sit on the left side of their trucks.

The left No Zone on a truck begins immediately behind the left-hand side of a truck’s cab and extends back at an angle to cover as many as two lanes of traffic.

Motorists should take care to avoid driving in neighboring left lanes. A good rule of thumb is to ensure that the mirrors of a large truck are visible at all times. Passing a semi-truck on the left side is much safer than passing on the right, but it’s still a good idea to do so quickly to avoid the truck’s left-side No Zone.

When truck operators fail to check their left No Zones for other drivers before merging or turning, they are much more likely to cause serious side-impact, rollover, and underride accidents. According to the NHTSA studies cited above:

• 11% of all fatal accidents between large trucks and other vehicles involved impact points on the left-hand side of a truck.
• 9% of all fatal truck crashes occurred when the front end of another vehicle collided with a left-side impact point on the truck in a T-bone collision.
• Another 9% of all fatal truck crashes were the result of another vehicle sideswiping a left-side impact point on the truck.
• Around 13% of fatal truck accidents that resulted in fatalities or incapacitating injuries involved left-side truck impact points.

The right side no-zone of an 18-wheeler contains one of a large truck’s biggest blind spots, which begins just behind the right-hand side of a truck’s cab. This blind spot extends back at an angle away from the side of a truck’s trailer, sometimes spanning as many as three lanes of right-hand traffic.

When drivers are situated on the right-hand side of a large truck, it can be difficult to tell exactly where the No Zone begins and ends. One of the most reliable ways of telling whether you’re in a semi truck’s right-side No Zone is to keep an eye on the truck’s mirrors. If you’re unable to see a truck’s side-view mirrors, or if the mirrors are in view but you can’t actually see the driver, you are in the No Zone and should relocate as quickly as possible.

Motorists who drive too closely to a truck’s right-hand side, pass a truck on the right, or linger in the No Zone are more likely to be involved in T-bone, sideswipe, rollover, and underride truck accidents. Reports from NHTSA suggest:

• 5% of all fatal crashes between large trucks and other vehicles in a single year involved impact points on the right-hand side of a truck.
• In nearly all of these fatal crashes, the front end of the other vehicle collided with the right-hand side of the truck in a T-bone or underride collision.
• Over a four-year period, 4.9% of fatal truck accidents that resulted in fatalities or incapacitating injuries involved right-side truck impact points.

A large truck’s rear No Zone is located immediately behind the truck’s trailer or any other cargo the truck is hauling. Because there is no rearview mirror in a semi-truck’s cab, the rear blind spot extends as far as 30 feet behind the back end of a trailer. This means that truck drivers have no way of seeing just behind them and can’t always tell whether someone is following too closely.

Other motorists should never tailgate any vehicle, especially commercial trucks. Doing so prevents them from seeing the road ahead, but it also prevents truck drivers from seeing their vehicle. If the flow of traffic forces truck drivers to slow or stop suddenly, tailgating drivers within the back No Zone can ram right into the rear end of the truck. Statistics published by NHTSA reveal that:

• 19% of all fatal accidents between large trucks and other vehicles in a single year involved impact points on the rear end of the trucks.
• In the majority of these fatal rear-end truck accidents, the front end of another vehicle collided with the rear end of the truck.
• Nearly 13% of truck accidents that resulted in fatalities or incapacitating injuries involved rear-end truck impact points.