Signalized Intersections

A Signalized intersection is operated by electronic traffic control devices. These devices are used by state and local agencies to separate conflicting movements along shared roadway spaces such as intersections. The more heavily traveled the intersection, the more likely it will be controlled by electronic signals. Most of the time, traffic control signals will sacrifice some speed and mobility to achieve greater safety. Considering the alternative, more collisions at intersections, these minor time delays are more than acceptable.

 “The basic function of signalized intersections is to sequence right-of-way between intersecting streams of users. These intersections thus serve multiple functions: they allow motorists to access new streets and change directions in travel; they are junctions for bike routes; and they provide a primary connection to and from activity centers for pedestrians. Intersections also serve as public right-of-way and include space for public utilities such as power and communication lines; water, sanitary sewer, and storm drainage pipes; and traffic signs and signal equipment.”  FHWA Pub p14

“All users must remain vigilant for potential conflicts with other road users.” FHWA pub p14 Drivers should watch for intersection signals and signage to know how to more safely cross the intersection. At the same time, drivers should also be alert to the actions of other drivers. Are they operating in a predictive manner? Are they aware of other vehicles on the road? Are they following the rules and laws for safer travel? Vehicle operators should be prepared for other drivers to do the unexpected and respond accordingly. For example, how many times have you encountered an approaching vehicle with his turn signal activated only to find that they did not turn? How many vehicles have you seen driving in the far left hand lane quickly cross one or more lanes of traffic to make a right hand turn? As an operator of a larger vehicle with a slower than average maneuvering and start from stop, only proceed when you are confident it is safe to do so.

As speed approaching the intersection increases, the amount of information that can be processed decreases. Drivers, especially RV drivers, need to keep diligent watch for regulatory and directional signage far in advance of the intersection to decrease potential error and increase chances for safety. When safe and appropriate to do so, slightly decreasing your speed as you approach and intersection can help you to more clearly determine how to properly proceed. Height, length, and width warning signs are often not seen until there is very little time to change course. If you drive a larger vehicle, look out for these signs.

No matter how clearly the intersection is marked, there will be those who do not obey the red light. Although almost all drivers agree that running a red light is unsafe and unacceptable, one in three drivers admitted to having run a red light in the past thirty days. Whether it was willful or because of distraction, a car passing through the intersection on a red light is a great danger and may cause serious injury or death to others.  As an RV driver, make sure you are driving at or below the speed limit as you approach an intersection so that you have time and space to stop before entering the intersection when you see the light turn yellow. Remember, it takes longer to start and stop these large vehicles: drive with that in mind. Once you are stopped at a red light, make sure you look all ways before proceeding on a green light. At any given intersection, someone runs a red light every twenty minutes. Don’t get caught by a hurried or unaware driver.

Unsignalized Intersections

Unsignalized intersections constitute the vast majority of intersections across the United States. These intersections are controlled with only Stop or Yield signs and some intersections have no controls at all. In recent years, 70% of all fatal crashes occurred at intersections not under the control of a traffic signal. These unsignalized intersections are usually found on more rural areas and have higher speed limits, thus increasing the rate of fatalities.

Uncontrolled intersections do not have any light or sign requiring the drivers in any direction to stop or yield.  While these only occur on very low volume roads, drivers should be aware of their surroundings and watch for all traffic whenever crossing any street. When approaching an uncontrolled intersection, slow down to watch for other traffic. If another vehicle is at or near the intersections, right-of-way rules apply. The vehicle that arrives first has right-of-way. If the vehicles arrive at the same time, the vehicle on the left yields to the vehicle on the right. Left turning traffic yields to all others, regardless of when they approached the intersection. No matter who has the right of way, do not proceed until you know it is safe to do so. Note: some states laws require all uncontrolled intersections to be treated as four-way stops.

Yield signs are typically used on minor roads or Y-intersections. Vehicles who have the yield sign should slow down and be prepared to stop when necessary. If there is no other traffic, they may carefully proceed. If other traffic is nearby, yield to intersecting traffic. A flashing yellow light should be treated as a yield sign.

Stop sign controlled intersections have at least one direction controlled by a stop sign. A stop sign calls on the driver to make a full and complete stop before entering the intersection. If a stop line or limit is on the pavement, the stop should be made behind that white line. Otherwise, you should stop before the crosswalk or entrance to the intersections. As stated above, right of way laws apply when there are two vehicles at the intersection.  Again, always make sure it is safe to proceed before crossing an intersection after stopping. A flashing red light should be treated as a stop sign.

Drivers should be aware of any intersection they encounter, especially those with only a stop or yield sign, or no sign at all.

For Further Study:
Proven Counter Measures
FHWA - Innovative Intersection Signals