Interacting With Other Users

Interacting With Other Users• Most collisions occur when two or more objects try to occupy the same space at the same time.

• Drivers must identify movement that could result in dangerous conflicts as well as judge the risk of two objects closing on each other

Closing Probabilities/Traffic Conflicts• Major types of crashes*

– Intersection related• More crashes than at any other location

– Rear end• More than 2 million crashes/year (tailgating)• Merging & exiting vehicles

– Lateral movement• Lane change• Merging & exiting vehicles

– Cyclist– Head-on

• Run off road (over correct)

– Single car• Run off road (too fast for conditions)

*INCR 2001 Report Breaking the Accident Chain

Common Conflicts:•Oncoming vehicles •Merging/exiting vehicles •Cars ahead of you •Cars behind you •Intersecting vehicles and pedestrians

Anticipate Errors

• Vision errors• Failure to yield right-of-way• Improper speed adjustment• Poor judgment of distance or space• Inadequate or improper vehicle control• Improper signals• Sudden actions to avoid objects

Clues to Problems

Read the clues to problems.

Be aware of the risk!

Communicating• Turn Signals

• Ky requires 100 ft before turn

• Beware of confusing signals

• Headlights• Double the distance at which you can be seen

• Horn• Brake Lights

• Tap lightly to signal intention to stop

• Flashers• Parking Lights

• Use only for parking

Intersection: Adjust Speed/Placement for Visual Search

Cover Brake!

Step 1 (Search)Identify Intersection Identify Signs, Signals, MarkingsCheck Rear Areas Search for Intersection Problems

Step 2 (Evaluate)Scan Open Side Areas.. 1stScan Closed Side Areas Look for Closed, Changing Frontal Areas

Step 3 (Execute)Adjust Speed/PositionMaintain Lane PositionStop behind Crosswalkor Proceed Through Open Space Area

IntersectionsMaster the ability to correctly estimate the interval needed to enter or cross a traffic flow.

1 sec, 2 sec, etc

Intersection Safety

• What types of crashes are likely to occur while waiting at a red traffic signal?– How can you protect yourself against these types of

crashes?

• Stop before crosswalk/stop bar

• Stop so you can see rear wheels of car in front of you

• Be sure cross traffic is stopping before you go

Driving in Traffic• Adjust speed and position

• To stay out of blind spots

• to avoid driving in a pack

• to allow time to assess, collect, and process traffic information

• Maintain adequate space margins• Position your car so you can observe actions

of drivers 4 to 5 cars ahead of you

• Increase for view obstructions

• Leave an area into which you can steer on at least one side of your car

Driving in Traffic • Meeting other traffic

– Avoid meeting large vehicles in reduced space

– Avoid meeting other vehicles as you approach non motorized users or stalled vehicles

– Avoid meeting other vehicles on slippery roadways such as bridges, shaded areas, or curves

• Following distance– When behind a large truck– When approaching a railroad crossing– In poor traction

Mid-BlockCrossing

What signs should you be reading in this situation?

Blind Intersection

The Stalled Vehicle

Come on, Good Buddy

Dropped Lane

Road Curves to the Right

What’s the risk?

When inertia overcomes friction, the vehicle fails to turn. The sharper the change in direction(more curve) the greater the need to reduce speed.

Road Curves to the LeftWhen inertia overcomes friction, the vehicle fails to turn. The sharper the change in direction(more curve) the greater the need to reduce speed.

What’s the risk?

Passing on a Two-Lane Highway

No oncoming vehicles for 3420ft if passing a vehicle doing 50mph!

Non-Motorized Users• Expect to be Challenged the Unexpected

Children in Traffic

Expressway Driving• Effect of high speed on braking distance• Effect of high speed on field of vision• Highway hypnosis• Effect of extended high speed driving• Presence of slower moving vehicles• Presence of faster moving vehicles• Entrance and exit ramps• Vehicles on shoulder (reentering)• Wind effect

Type of Interchanges

Trumpet Cloverleaf Diamond

Cloverleaf Interchange

No gap to enter

Entering traffic not matching speed

Sudden lane change to exit

Exiting vehicle returns

Sudden slowing

Entering an Expressway

AMBULANCE

AMBULANCE

AMBULANCE

AMBULANCE

1

2

3

4

1. Directly identify gap or vehicle following gap

2. Transfer visual to rear/side mirror

2a. Begin accelerating to highway speed

3. Head check of blind spot (fast glance)

3a. Check intended path

3b. Accelerate into gap - if there is a problem, DO NOT STOP ON RAMP, go into emergency strip

4. Adjust speed to highway limits; establish interval

Selecting the Best Travel Lane

Approaching Merge Ramps

• Be aware of approaching merge ramps.

• If possible move out of the right hand lane to avoid a closing conflict.

• If impossible to move left be prepared to adjust speed to accommodate merging vehicles

Exiting an Expressway23

Exit Ramp

Deceleration Lane1

Driving Through a Weave Lane

What are the risks?

Who has the right of way?

Freeway Driving

Dealing with Large Trucks

•Weight difference

•Momentum

•Acceleration

•Deceleration

•Turns

•Visibility