MODULE 8
Objectives: Students will learn how to recognize
driver and vehicle limitations in adverse
conditions, use proper seatbelts, airbags, child
restraints, and vehicle imbalance
Topics covered:
— Visibility in adverse conditions and extreme weather
conditions—learn to recognize driver and vehicle
limitations
to weather conditions
— Protecting occupants—learn to use airbags and safety
restraints
— Roadway and vehicle technology—learn to use vehicle
protection features
— Traffic loss concerns—learn to recognize vehicle
imbalance
VISIBILITY CONDITIONS
At night, visual acuity is severely limited—our eyes
adjust
very quickly to light but very slowly to darkness
If a driver is blinded by the lights of an oncoming
vehicle,
he/she should reduce speed, look to the right, and
glance
briefly ahead
—Approximately 90% of our driving clues depend on vision
—One method for reducing glare at night is to clean your
windshield—dirty headlights can reduce visibility up to 90%
North Carolina law requires the use of headlights
whenever the windshield wipers are in use
* the air conditioner will help to defog interior windows
—Overdriving your headlights means that you cannot stop
in the distance illuminated by your headlights
Visibility Conditions

When driving at night with low beam headlights, the
maximum safe speed is 45 mph
When driving in fog, you should use low beam lights and
the maximum safe speed is 45 mph

A wet roadway is most slippery when the rain first begins- as more streets and parking lots are built, flooding
problems will increase
 Bridges and overpasses can be more hazardous than
other roads during cold weather, because those surfaces
freeze before other road surfaces
— Hydroplaning
is caused by the buildup of water between
the vehicles tires, road surface, loss of steering, and loss
of braking
— Two
dangers of driving through deep water are that (a)
the roadbed may be washed away and (b) water might
cause your engine to stall out
Visibility Conditions
Nearly 1/2 of all flash flood fatalities are vehicle related
To dry wet brakes, you should brake gently using your left
foot while accelerating with your right foot
If you begin to slide on a slick surface, look and steer in
the direction you want to go
— It is not safe to stay close to the shoulder when driving
through water
Sand, gravel, or even cat litter can help tires gain traction
on slick surfaces
Dust or sand storms can reduce visibility to ½ mile or less,
strike with little warning, and often damage oil and air
filters
 Buffeting results from high winds—when driving into
a headwind, you may need to accelerate more
 Before starting a vehicle in snow, check to be sure that
the exhaust system is clear—the use of cruised control
does not help control a vehicle in snow
Protecting Occupants
North Carolina law requires all front seat passengers and
any person less than 16 to wear a seat belts
 When driving an airbag equipped vehicle
 Sit at least 10 inches from the steering wheel—tilt the
steering wheel should be tilted toward the chest
 Your hands should be on the lower half of the steering
wheel: 9:00/3:00 or 8:00/4:00.
 The lap belt should be worn across the hips

In 2000, 60% of the teens killed in motor vehicle related crashes were
not wearing a safety belt

An airbag…..
 Automatically inflates in frontal crashes at speeds up to
200 mph
 Distributes the force more evenly across the body
Protecting Occupants and Roadway Features
Sixty percent of teens killed in the year 2000 motor
vehicles related crashes were not wearing a seat belt
 Even if your vehicle has air bags, you need to use safety
belts—new vehicles now may be equipped with side air
bags
 Pregnant women should always wear seat belts
 If an infant must ride in the front seat, the air bag
should be turned off: the safest place for children is in
the back seat
 Adjust the position of the head restraint to be just above
the ears
 When you ride in a moving object, your speed is equal to
the speed of the moving object
 It is not advisable to remove the radiator cap to release
steam and cool an overheated engine
 Rumble strips are grooves or rows of raised pavement
markers placed on the shoulder to alert inattentive
drivers

Roadway Features
Message signs are used to warn drivers of dangers ahead
 Breakaway sign support posts are break-away systems
designed to cause less damage and impact to vehicles and
make it safer for drivers upon impact
 Crash attenuators are vinyl liquid or sand filled drums
that have been installed in a specific geometric array in
front of the hazards
 Median barriers are prefabricated islands that are placed
in the center of the roadway leading up to a highway-rail
grade crossing
 Extruder terminals reduce hazards of guardrails—the
kinetic energy of the impacting vehicle is absorbed by the
force required to reduce the W-Beam shape of the
guardrail to a flatter section
 Tire pressure increases as the tires get hot—the
recommended antifreeze/water mixture is 50/50

Automotive Technology
ABS—(Anti-Lock Braking System) allows the driver to
steer while braking—prevents tires from sliding and
generally shortens stopping distances on wet surfaces
 In vehicles without ABS, a quick jab of the brakes may
help control front wheel traction loss
 Traction Control sends power to wheels with most
traction—designed to activate brake sensors, which do not
allow the wheels to spin
 Suspension Control adjusts vehicle balance through
adjustment of fluid or air pressure when too much weight
is suddenly transferred to a given shock absorber or strut
 ESP—(Electronic Stability Program) activates when
vehicle is not going in the direction it is being steered

Traction Loss Concerns
Good traction starts with your vehicle’s tires—a drivers
first indication of traction loss comes from motion based
sensory input
 In skid control, it is critical that the driver look where
he/she wants the car to go and steer in the intended
direction
 Traction control sends power to wheels with most traction
and allows a vehicle to start, stop, and/or change direction
 Under-steering results from loss of front traction—a
good technique to minimize under-steering is to slow
down before entering a curve or turn
 In rear wheel loss of traction, the rear wheels are
trying to lead
 The following conditions may affect traction:
 Surface Materials
 Surface Conditions
 Weather Conditions
