Driving: Chapter 11 - Intersections and Freeways

• Chapter 11 discusses intersections and freeway driving

Chapter Objectives

• Identify and approach intersections effectively
• Stop safely before entering an intersection
• Navigate turns at intersections
• Negotiate roundabouts
• Execute turns on expressways
• Merge onto and exit freeways safely
• Maintain proper vehicle positioning for freeway driving

Intersections

• Intersections are risky due to vehicles crossing paths at various angles.
• Understanding intersection configurations is crucial for safe travel.

Identifying Intersections

• Recognize intersections by searching for warning signs and crossroads ahead
• Flashing yellow traffic signals often mark intersections
• Intersections can include road or street crossings, pedestrian crosswalks or fire stations
• Some intersections use multiple-lens traffic signals or stop/yield signs to assign right-of-way.
• Controlled intersections use traffic signs and/or signals to indicate which road users must yield
• Uncontrolled intersections require yielding based on right-of-way rules, common in residential areas without traffic control devices

Approaching Intersections

• Always approach intersections with caution, irrespective of the environment (city, highway, or rural area)
• Position correctly in the proper lane.
• Adjust speed to allow time for intersection search and smooth stopping if needed.
• Be aware that other drivers may disobey signs and signals
• Increase visibility by driving with low-beam headlights, even in daylight

Search Patterns

• Adjust search patterns based on the design and controls of the intersection
• Search all areas, being mindful of limited visibility
• Identify control devices and assess the sharpness of curbs
• Sharper curbs often indicate more restricted views of the turning street

Intersection Tips

• Time your arrival to avoid unnecessary stops, especially at traffic signals
• If stopping, do so well behind the vehicle ahead to maintain visibility
• When approaching a stop sign intersection with cross-traffic, look left first
• Approaching traffic from the left is typically closer
• The general search pattern for turning at a T intersection is left → right → left
• The general search pattern for safely entering a four-way intersection is left → right → ahead → left

Traffic Signals

• Some drivers use pedestrian crossing signals to anticipate when a green traffic signal will turn yellow
• The driver should search the intersection thoroughly for hazards

Stopping at Intersections

• At intersections with white stop lines (limit lines or stop bars), stop before any part of the vehicle crosses the line
• At intersections with crosswalks but no stop lines, stop before the front of the vehicle enters the crosswalk
• At intersections with stop signs but no lines or crosswalks, stop before the front of the vehicle enters the intersection with the cross road or street

Finding a Safe Gap in Traffic

• Judge when to proceed across or turn when it is legal and safe
• Accurately judge the size of traffic gaps
• Gap size depends on the time needed to clear the intersection or turn and join traffic flow; turning requires more time
• In urban areas, a time gap of 8 to 9 seconds is needed to turn right onto a street with traffic moving at 30 mph
• Increasing the time to 11 seconds is needed when turning left
• Identify a large enough gap so other drivers are not forced to brake

Turning at Intersections

• Turn from the far left or far right lane of traffic moving legally in the intended direction
• Enter the first traffic lane in the direction of the turn unless otherwise indicated
• At intersections permitting turns from multiple lanes, turn into the lane corresponding to the lane you turned from
• After turning, accelerate to match the speed of traffic

Turning Right on Red

• Drivers can turn right on a red traffic signal unless prohibited by a regulatory sign
• Drivers are not obligated to turn right on red.
• Stop fully and yield the right-of-way to all other road users before turning right on red
• Search for and yield to pedestrians near the intersection, who may be in the crosswalk

Turning Left on Red

• Some jurisdictions permit drivers to turn left at red signals
• Laws vary, with some places requiring both streets to be one-way
• Drivers are not obligated to turn left on red even where lawful
• Stop fully and yield the right-of-way to all other road users before turning left on red
• Search for and yield to pedestrians, who may be directly in your path

Additional Tips for Left Turns

• Turning left across oncoming traffic is hazardous and requires an adequate gap
• Drivers turning left must yield the right-of-way to all oncoming vehicles
• Even with protected left turns, ensure the intersection is clear before turning
• Be mindful that line of sight can vary depending on the intersection's offset
• Negative offset intersections are the most hazardous, limiting the view of oncoming traffic
• Zero offset intersections have limited lines of sight
• Positive offset intersections offer maximum lines of sight

Judging Safe Intersection Entry

• Use positive offset intersections for left turns when possible
• Be cautious if an oncoming driver waves you to turn, as they may not have assessed the path of travel
• Never rely on another driver’s judgment to determine if it is safe to proceed

Roundabouts

• Roundabouts are circular intersections offering multiple advantages over conventional intersections
• Jurisdictions are increasingly incorporating them into new and redesigned roads
• Roundabouts assign the right-of-way with yield signs, avoiding unnecessary stops
• Reduce driver waiting times by up to 20%
• Roundabouts are significantly safer because no driver turns left in front of another driver
• The risk of head-on collisions is reduced, resulting in a decrease as high as 75% serious injuries and fatalities
• Tend to have fewer crashes at lower speeds with smaller impact angles reducing intersection crashes by 40%
• Roundabouts do not use electricity, saving money and resources
• Roundabouts are environmentally friendly because vehicles spend little or no time stopped, with less time idling with less pollution

Navigating Roundabouts

• There are three key parts to driving through a roundabout; Approaching, driving within, and exitiing
• Reduce speed when approaching, always move to the right, and yield to crosswalks and vehicles in the roundabout
• Yield signs control the right-of-way, often paired with yield lines Position the vehicle in the correct lane for the intended exit when approaching multi-lane roundabouts before entering
• After entering, maintain a slow speed and move in a counterclockwise direction
• Prepare to stop for any road user entering the roundabout, even though they should yield
• If in a multi-lane roundabout, maintain the lane position and watch for drivers who may not stay in their lane
• Signal right when near the road or street to exit the roundabout, communicating your intention to exit to other drivers
• Search for and yield to pedestrians in the crosswalk beyond the roundabout
• Cancel the right turn signal after turning onto the street or road beyond the roundabout
• Exiting at the first road/street is like turning right (90 degrees)
• Exiting at the second road/street is like going straight (180 degrees)
• Exiting at the third road/street is like turning left (270 degrees)
• Circle allows for reversing direction (360 degrees)
• Continue around again if you miss the intended exit point

Expressways and Freeways

• Expressways and freeways carry high volumes of traffic at faster speeds
• Multiple lanes of traffic in the same direction
• Medians and physical barriers separate traffic traveling in opposite directions
• Wide, paved shoulders
• Relatively open lines of sight
• Risk-reducing engineering standards like gore areas, rumble strips, pavement markings, clear signage and mile markers
• The primary difference is that expressways have intersections, while freeways use interchanges

Turning on an Expressway

• Involves using median crossover intersections for left turns and U-turns
• Median crossovers can be specific to U-turning or used for turning left
• Strategically position to maintain as much line of sight as possible
• Best reduce risk when U-turning or turning left, position your vehicle to the far side of the crossover
• Yield the right-of-way to all other road users before executing a U-turn or left turn

Driving on Freeways

• Cloverleaf and diamond interchanges are common
• Drivers typically enter and exit from the right lane, but some interchanges require entering/exiting from the left
• Scan ahead, interpret signs, and position the vehicle in advance
• Entering, driving on, and exiting are the three steps to using a freeway
• Entering is usually the most challenging because it involves turning from a surface street onto a freeway

Merging onto a Freeway

• Merging is the blending of vehicles to maintain smooth traffic flow
• Yield the right-of-way to vehicles already on the freeway but the drivers already on the freeway should adjust the speed and position
• Search for a safe gap in traffic (at least 4 seconds)
• Maintain space margin and continue searching
• Signal and accelerate to the speed of freeway traffic in the acceleration lane
• Do not stop in the acceleration lane unless necessary
• Adjust the speed to match the freeway traffic near the end of the ramp/start of the acceleration lane
• Steer smoothly into the lane and cancel turn signal
• Avoid entering the freeway at a sharp angle

Freeway Driving Position

• Focus should be on speed, space, and position
• New drivers prefer the rightmost lane
• Position on the highway should be in the right as practical but scan and adjust speed in the right-lane
• The middle lane is generally safest for through traffic on freeways with three travel lanes

Signals

• Ramp traffic signals are not part of a freeway design
• Some high-traffic areas use two-lens, metered signals at freeway entrance ramps
• When dark, drivers choose when to enter; when active, drivers stop at red and proceed on green (one vehicle per green)
• Metering signals help regulate traffic flow onto freeways, allowing drivers on the freeway to adjust more easily

Courtesy Lane Changes

• Despite the the right-of-way, merge cooperatively
• Change lanes to the left when if a driver to enter from the right
• Merge signs indicate two lanes needing to merge into a single lane
• Lanes signals is when a new lane being added to the existing one

Freeway Signage

• Destination and guide signs show mileage to interchanges and simplify navigation
• Place signs at consistent intervals to help drivers locate and plan exits

Freeway Crashes

• High traffic allows people and products to travel safely and efficiently
• Occur less but affect more people
• Crashes require to move vehicles to a shoulder or the next exit
• Sooner the better the crash is removed the sooner the other traffic can be on their way

Exiting Freeways

• Know the exit well in advance
• Use green and white guide signs to find the exit
• Move into the lane closest to the deceleration lane
• Signal and steer into the deceleration lane as soon as you reach it
• Maintain freeway speed until transitioning to the deceleration lane
• If the interchange has a short deceleration lane, slow down only as much as necessary to exit
• Posted exit ramp speed limits are low due to curved roadway design
• Yellow speed limit signs warn of the "maximum safe speed" under ideal conditions
• Be aware of the adjustment time and to those significantly lower speeds

Weave and Acceleration Lanes

• Some interchanges have weave lanes ("speed change" lanes) allowing for entering and exiting
• Entering drivers use the weave lane to increase speed
• Exiting drivers use a weave lane to slow down
• Weave lanes require cooperation from all
• Both types should maintain alertness and be considerate of other road

Velocitation and Highway Hypnosis

• The driver can become used to how the vehicle feels, how the scenery appears, and how it sounds when on the freeway
• Driving at a higher speed is known as Velocitation
• Can result in entering an exit ramp to fast
• Surface limits are challenging
• Trance-like states can occur during long drives when drivers fail to rest
• Taking breaks every 100 miles or every two-hours can avoid highway hypnosis