Intersections and Safe Driving

Intersections have been described as one of the most complex traffic situations that motorists, pedestrians, cyclists and other road users encounter daily!

Intersection crashes are one of the most common types of crashes - and also a crash type with severe consequences.

The U.S. Department of Transportation estimates that 43% of motor vehicle crashes occur at intersections or are "intersection-related”.

Knowing the major risks of an intersection collision and how to avoid them can help to minimize your chance of a crash. In this section, we would like to assess these risks and provide advice for safer driving at intersections.

What is an intersection?

Intersections are locations where two or more roads meet, cross or converge and traffic moving in different directions all come together. They come in many different designs, configurations, and sizes. In traffic design, intersections can contain as many as six streets converging. For example, a six-way intersection can involve the crossing of two perpendicular streets, with yet another street crossing them diagonally.

The crossing and turning manoeuvres that occur at intersections create opportunities for vehicle-vehicle, vehicle-pedestrian, and vehicle-bicycle conflicts, which may result in traffic crashes. The definition in itself emphasizes the inherent danger of an intersection, describing an area where vehicles may come into “conflict.”

Types of intersection crashes

We have all experienced the sounds of screeching of tyres followed shortly thereafter by the brutal sound of metal hitting metal, typical of a crash at an intersection. A number of different intersection crash types occur, including:

Collisions between oncoming vehicles, particularly when one is turning across traffic
Rear-end crashes - often occurring because the following driver is distracted and does not realize the lead driver has stopped.
Side impact collisions or “T-bones”. These types of accidents typically involve a driver on one side running a red light, be it intentionally or while trying to make it through an intersection before a yellow light turns red.
Side-swipe collisions where one or more vehicles are turning.
Collisions into vulnerable road user such as pedestrians and cyclists while turning.
Crashes at Level Crossings/ Rail Crossings

Causes of Crashes at Intersections

We need to ask “Why are there so many collisions taking place at intersections?”

Studies show that two of the most common reasons for intersection collisions are driver negligence and recklessness.
Running a red light together with ignoring the yield and stop signs are the most common causes of crashes in city traffic.
Inattention and inadequate sight distance to oncoming traffic when turning left or right.
Lack of intersection visibility (road users are not aware of the intersection)
Driver inattentiveness includes not observing other traffic at an intersection while being distracted by cellular phones, car radios etc.
Tailgating which includes an attempt to forestall a red light by speeding up and bumping on another vehicle.
High approach speeds to the intersection.
Crashing into the sides of long vehicles that are often not visible to approaching drivers. [This may be due to burned-out lamps, missing reflectors or the lack of conspicuity striping.]
Collisions with pedestrians and other vehicles not visible to approaching trucks or failing to adhere to traffic control devices.
Poor visibility in dense fog, smoke or mist.
Lack of safe following distances
Complex intersection layout
Poor road surface condition or faulty intersections/traffic lights and signals.

Why are Intersections so dangerous?

Too many road users are killed and left with debilitating injuries from preventable crashes at intersections. Road users must accept that every intersection is dangerous due to the constant flow of traffic- day and night!

But why are these crashes so dangerous?

Road users come into contact with drivers who are, in a hurry, or plain clumsy, aggressive, careless, impatient, distracted, sleepy or drowsy, driving under the influence, and some of them have suicidal driving tendencies.
Intersection collisions often result in side-impact / T-bone collisions.
Side impacts have higher rates of deaths and serious injuries because there is little vehicle protective structure to safeguard occupants in the struck vehicle.
In sideswipe/ broadside collision vehicles are often knocked off course and into the second collision into oncoming traffic.
With the broadsiding vehicle putting its full force straight into the relatively unprotected side of the other vehicle, T-bone accidents are even more likely to cause serious injuries than sideswipe accidents.
Once a vehicle is off its intended course, the occupants face the risk of further collisions and traumas, crashing into guardrails, telephone poles, and other vehicles.
If the force of the collision is strong enough, the broadsided vehicle may roll over completely, especially if it is knocked onto a sloping road shoulder.
The chances of avoiding serious injury or death reduce dramatically above 50 km/h for side impacts for the most modern types of cars, and is far less than this for older vehicles, and particularly for vulnerable road users.
Intersection crashes can become deadly if one or both vehicles were moving at high speed when the collision happened.
Common injuries that victims may suffer include traumatic brain injuries, spinal cord injury, limb amputation, severe burns and bone fractures
Older pedestrians are particularly at risk for injury or death when crossing intersections.

Reducing crashes at Intersections

Human error is the biggest contributing factor to road crashes. There are, however, aside from addressing driver behaviour, road engineering and design measures that could assist towards safer intersections. We would like to share some of these:

Roundabouts are an effective way of reducing the speed of traffic at intersections reducing the likelihood of high-speed right-angle collisions.
Far fewer crashes, and less serious, occur at intersections with roundabouts than at intersections with signals or stop signs.
Clear road markings and signing are low-cost methods of improving safety at intersections.
Red light violations can be enforced and offenders penalized via red light cameras or the "photo radar".
Any vehicle crossing the sensors on red light triggers the camera and a photo is produced showing the car, licence plate, together with the date and time of the violation.
Improving traffic signal timing which can reduce rear-ending and brief red-in-all directions signals could prevent certain cross-traffic collisions.
Improving lighting at intersections reduces collisions at night - and also reduces criminal activity at intersections.
Improving the signal visibility such as by making them larger, brighter, or by installing an additional signal head.
Pedestrians can be given time to start across intersections before the turning vehicles are allowed there.
At dangerous locations, the conversion of two-way, with four-way stop signs may reduce crashes.
Innovative use of "traffic calming" measures such as speed bumps, rumble strips and street narrowing.
Adjusting the speed limits to be appropriate for a given street.
Implementing scholar patrol in front of schools where children cross intersections.

Safe Driving at Intersections

Being aware of the laws and taking precautions behind the wheel are important and useful steps to avoid a crash in an intersection. Plan your trip to avoid rushing to make an appointment. Plan ahead, anticipate potential traffic delays and leave early for your destinations.

We would like to offer some suggestions for safe driving at intersections:

Approaching the Intersection

Drive defensively, anticipating problems and situations with heightened caution and attention during congested traffic times such as rush hour.
Be patient - Impatience increases emotions and decreases attention.
Think about what other drivers might do as you approach intersections, particularly when you are altering your path approaching an intersection.
Avoid all driver distractions - all your focus is required when approaching an intersection.
Always, always wear your seatbelt and insist that everyone in your vehicle wears theirs.
A passenger not buckled in will become a projectile threatening the safety of other passengers in a collision.
Do not speed at intersections - a driver driving too fast when approaching a crossing, may not be able to completely stop when necessary.

Considerations at Intersections with Traffic Lights

Know the rules of the road at intersections and specifically at traffic lights.
Emergency vehicles always have the first right-of-way. Remain stopped and still until the emergency vehicle has completely cleared the area of the intersection.
Before you move, check to be sure other emergency vehicles are not following the first one.
A green light means proceed with responsible caution; yellow signals mean stop before the white line unless you are too close to do so safely. A red light means stop.
Yellow lights do not provide a signal to motorists to go faster through the intersection.
Good judgment must be used to avoid violating the subsequent red light, at the same time avoiding stopping in the middle of the intersection.
Blinking amber lights alert the driver to be cautious in approaching and proceeding through an intersection, and to give way to all pedestrians and vehicles crossing the driver's path
Blinking red lights require that motorists stop at the intersection [and yield to all pedestrians crossing their path] before proceeding through [in the same way as for a 4-way stop].
Look at your left and right and pay attention to other drivers who are trying to beat the signal change.
Be extra cautious in the rain and icy cold weather where roads may be slippery.
Always assume when approaching an intersection that crosses traffic or pedestrians may not obey traffic control devices or yield right-of-way.
If you are the first vehicle at the light, stop before the painted stop line, before crosswalks or, if neither is present, at the intersection itself without entering the intersection.
Come to a full stop and leave enough space between you and the vehicle stopped ahead of you so that you can steer around it if it were to become disabled.
When the light turns green, scan the intersection before you move forward - Take your time to ensure that the intersection is all yours.
With delayed green, some drivers believe they are entitled to those few extra seconds and speed up rather than slow down
Beware of those accelerating over the red light and the driver eagerly anticipating the green light.
Do not follow other vehicles very closely (tailgate). They might stop suddenly.
Always watch out for pedestrians, cyclists and motorcyclists.
Pedestrians always have the right-of-way. If a pedestrian is crossing illegally (jaywalking), you must still yield the right-of-way.
Use your turn signals appropriately. Without the proper signals, another driver may not be aware that you are turning and may pull out in front of you or hit you.
Give a turning signal before you turn or change lanes and be sure that you are in the correct lane before you signal your intention to turn.
Maintain your vehicle. Malfunctioning warning lights (turn signals, brakes, headlights) make it difficult for other motorists to predict your actions on the roadway.
Obey all traffic signals and never assume it is safe to turn!
Avoid entering an intersection when traffic is backed up on the other side, you may be unable to leave the intersection before the light change and might be stuck in the middle.

Unregulated intersections

Unmarked intersections that have no controlling lights or signage should be treated as full stops in all directions before proceeding.
Where traffic lights are out of order the rules for a 4-way stop apply.
At an intersection regulated only by a stop sign at one of the cross streets, the unregulated flow of traffic has the right-of-way.
The vehicle reaching the intersection and stopping first always has the right-of-way.
Vehicles turning left should always yield to vehicles approaching from the right and proceeding straight.

There is a need for special caution when large trucks and farming equipment approach intersections.

Beware of tractors pulling trailers. Collisions involving trailers often cause extensive damages to vehicles and other properties.
Truck drivers crossing an uncontrolled intersection must allow enough time to clear the entire intersection with the rear of the vehicle without interfering with cross traffic. They may not be visible to oncoming traffic, and oncoming drivers may be inattentive or impaired.
Be especially aware of uncontrolled intersections at dawn, dusk and during nighttime hours where you may not see a long trailer following a truck.
Be alert to trucks and trailers where the sides might not be clean or the reflective devices and other measures to ensure increased visibility are not operational.
Truck drivers need to ensure side lamps and reflective devices are operational after a flatbed trailer has been unloaded as they can be more difficult to see when empty.

Conclusion

Besides compliance with the rules, driver etiquette is the first measure toward improving intersection safety. The intersection is no place for selfishness. Be prepared to be the safer driver by showing courtesy towards other drivers!

Also view:

Safe Driving at the Roundabout / Traffic Circle

Load Shedding and Road Safety

Scholar Patrol and Road Safety

Level Crossings and Road Safety

Dashboard Camera Recorders and Road Safety