Preventing Crashes at Intersections

inter_Hwy_24_Woodmen

On Thursday, a semi was headed westbound on Highway 24 when a pickup pulled in front of it at the intersection of Woodman in Falcon, Colorado. The truck driver was ejected from the truck as a result of the crash, resulting in fatal injuries.

40% of Crashes

About 40 percent of crashes are at intersections. Intersections range from complex expressway interchanges to simple, rural crossroads. In an uncontrolled intersection, there are no traffic control devices.

What is one of the main causes of intersection crashes?

In a study of intersection crashes by the NHTSA’s National Center for Statistics and Analysis, when comparing intersection crashes with non-intersection crashes, it was found that the “critical pre-crash event” — defined as an event that made the crash imminent (i.e. something occurred that made the collision inevitable) — was “turned with obstructed view.” NHTSA analysts  found  “turned with obstructed view”  occurs at intersection crashes  335 times more than at non-intersection crashes, usually in left-turns.

It is found that regardless of type of traffic control device, traffic signal, or stop sign, illegal maneuver and inattention were observed significantly more than expected in crossing-over crashes, while turned with obstructed view and misjudgment of gap or other’s speed in turning-left crashes.

False assumption of other’s action was found as the most significant critical reason in turning-left crashes at traffic signal and in turning-right crashes at stop sign.

The next most prevalent critical reason for an intersection crash was “inadequate surveillance,” appearing about 6 times more often in intersection-related crashes than in non-intersection-related crashes.

Other reasons for intersection crashes include: illegal maneuver (4.1 times), false assumption of other’s action (3.8 time), misjudgment of gap or other’s speed (3.1 times). Reasons may vary by type of maneuver, whether vehicles were turning right, left, or going straight through the intersection.

The results show that significantly more than expected drivers were assigned critical reasons such as external distraction, false assumption of other’s action, misjudgment of gap or other’s speed and turned with obstructed view when they were turning left at intersections controlled by traffic signals. Also, significantly more than expected drivers were assigned critical reasons such as internal distraction, inattention, illegal maneuver, too fast or aggressive driving behavior, and critical non-performance error when they were crossing over at intersections controlled by traffic signals.

In short, if a crash happens at an intersection, the crash only occurred because one or both drivers made some sort of error. One driver may have misjudged the other driver’s speed or closing gap, while the other driver may have misjudged the other driver’s intentions, or may not have been paying attention at all. The result is chaos.

The results also show that significantly more than expected drivers were assigned critical reasons such as inadequate surveillance, misjudgment of gap or other’s speed and turned with obstructed view when they were turning left at intersections controlled by stop signs. In addition, significantly more than expected drivers were assigned critical reasons such as inadequate surveillance, inattention, external distraction, and illegal maneuver when they were crossing over at intersections controlled by stop signs. The crashes characterized by turning-right at stop sign have false assumption of other’s action assigned as critical reason significantly more than expected

Some Intersection Safety Tips

Here are some defensive driving tips for intersections . . .

• If you are stopped and a vehicle approaches with the turn signal on, do not assume the signalling vehicle is going to turn: wait until the vehicle starts the turn so you know for sure, before pulling out.

• Approach intersections assuming that cross traffic may not obey traffic control devices and anticipate the need for collision avoidance.

See and be seen. Keep vehicle lights and reflective devices wiped clean at every stop, and assure that all lights are operational. Keep the headlights on 24 hours of the day.

Rock and roll. Be mindful of the “A pillar” blind spot where the cab meets the ends of the windshield. This can obscure vision. Rock and roll in the seat to look around the pillars.

obscured view

This truck had a number of objects dangling in the driver’s view, when it was hit by a train. 

• Keep the windshield and mirrors clean and be sure the driver’s view is not obstructed.

• Use a window-wash treatment as Rain-X in bad weather. Keep a spare jug of window wash in the truck in winter.

• When practical, avoid making left turns. UPS follows a no-left-turn policy in about 90% of their turns.

• Always be ready to yield right of way at an intersection, to avoid a collision.

Cover the brake at intersections. Physically move your right foot from the throttle to over the brake pedal.

• Never signal another driver to proceed. The driver may not look and end up in a collision.

Know any other great intersection-safety tips? Please share them.

obsecured view

Thank you for reading this and have a safe weekend.