Commercial Driver License Handbook

Section 2: Driving Safely

This section is for all commercial drivers

This section contains general knowledge and safe driving practices which all commercial drivers should know. You must take a test on this information to get a CDL.

This section does not contain information on air brakes, combination vehicles (tractor semitrailer, doubles/triples, or towing trailers), or buses. You must read other sections to get this information if it applies to the type of vehicle(s) you wish to drive.

We have included some basic information on hazardous materials and wastes. Section 9 has more detailed information on hazardous materials/wastes.

Vehicle Inspections

Safety. Safety is the most important and obvious reason to inspect your vehicle. A vehicle defect found during an inspection could save you problems later. You could have a breakdown on the road that will cost time and dollars, or even worse, a crash. Federal and state laws require inspection by the driver. Federal and state inspectors also inspect commercial vehicles. An unsafe vehicle can be put “out of service” until the driver or owner has it repaired. Do not risk your life or the life of another in an unsafe vehicle.

Pre-Trip Inspections

Pre-trip Inspection. Do a pre-trip inspection before each trip to find problems that could cause a crash or a breakdown. A pre-trip inspection should be done routinely before operating the vehicle. Drivers must complete a vehicle inspection report in writing each day. Review the last vehicle inspection report. Make sure the vehicle has been released for service by the maintenance mechanics, if applicable. The motor carrier must repair any items in the report that affects safety and certify on the report that repairs were made or were unnecessary. Remember, when you get behind the wheel, you (not the mechanic) are responsible for the safe operation of the vehicle. If the defects have been repaired, sign the previous driver’s report. There is detailed information on pre-trips in Section 10 of this handbook.

En Route Inspection

During a trip you should:

• Watch gauges for signs of trouble.
• Use your senses to check for problems (look, listen, smell, and feel).
• Check critical items when you stop.
  — tires, wheels, and rims
  — brakes
  — lights and reflectors
  — brake and electrical connections to the trailer
  — trailer coupling devices
  — cargo securement devices
  

After Trip Inspections

After-Trip Inspection and Report. Inspect the vehicle at the end of the trip, day, or tour of duty for each vehicle you operated. It may include filling out a vehicle condition report listing any problems you find. The inspection report helps the motor carrier know when the vehicle needs repairs.

Inspections—What To Look For

As you approach the vehicle, notice its general condition. Look for damage. Is the vehicle leaning to one side? Look under the vehicle for fresh oil, coolant, grease, or fuel leaks. Check the area around the vehicle for hazards to vehicle movement such as people, other vehicles, objects, low hanging wires, or tree limbs, etc.

Check that the parking brakes are on and/or the wheels are chocked. You may have to raise the hood, tilt the cab (secure loose objects first), or open the engine compartment door. Check the following:

• Tire Problems. It is dangerous to drive with bad tires.
  Remember: After a tire has been changed, stop a short while later and recheck the tightness of the wheel fasteners.
• Wheel and Rim Problems. A damaged rim can cause a tire to lose pressure or come off.
• Bad Brake Drum or Shoe Lining Problems. It is dangerous to drive with brake problems.
• Steering System Defects—(Figure 2-1) A poorly maintained steering system can cause steering problems.
  
  
  
  
• Suspension System Defects—(Figures 2-2 through 2-4) The suspension system supports the vehicle and its load and keeps the axles in place. Broken suspension parts can be extremely dangerous.
  
  
  

• Exhaust System Defects. A broken exhaust system can let poisonous fumes into the cab or sleeper berth.
• Emergency Equipment. Vehicles should be equipped with:
  — fire extinguisher(s) (when required)
  — spare electrical fuses (unless equipped with circuit breakers)
  — warning devices for parked vehicles (i.e., three reflective warning triangles)
• Cargo (trucks). Before each trip, inspect cargo for:
  — overloading
  — correct balance
  — securement
  — proper papers and placarding (if the cargo contains hazardous materials or wastes which require placarding)

• Lights and Reflectors. Reflectors should be clean and the proper color (red at rear). Verify that the following lights are clean, operating, and the proper color:
  — headlights (high and low beams)
  — turn signals
  — brake lights
  — running lights
  — emergency flashers
  NOTE: All corresponding dash display lights should be checked also.

Get In Vehicle

• Turn off lights not needed for driving.
• Check for all required papers, trip manifests, permits, etc.
• Secure all loose articles in cab that might interfere with operation of the controls or hit you in a crash.
• Start the engine.

Check The Brake System

Test Hydraulic Brakes.If the vehicle has hydraulic brakes, pump the brake pedal three times. Then apply firm pressure to the pedal and hold for five seconds. The pedal should not move. If it does, there may be a leak or other problem which must be repaired before driving.

If the vehicle has air brakes, follow the checklist marked with an asterisk (*) described in Section 5 of this handbook.

Test Parking Brake. First fasten your seat belt. Then allow the vehicle to move forward slowly and apply the parking brake. If the vehicle does not stop, get the brake repaired before you drive the vehicle.

Test Service Brake. First fasten your seat belt. Then allow the vehicle to move forward about five miles per hour and push the brake pedal firmly. If the vehicle “pulls” to one side or the other, or if there is any unusual brake pedal “feel” or delayed stopping action, the service brake may need repair before you drive the vehicle.

Buses must also be inspected for:

• Fire extinguisher.
• Passenger entry doors and emergency exits.
• Seats and bus interior.
• Baggage compartment.

If you see, hear, smell, or feel anything that might mean trouble–check it out. Do not drive an unsafe vehicle.

Safety Inspection. Truck and truck tractor drivers should inspect their vehicle within the first 25 miles of a trip and every 150 miles or every 3 hours (whichever comes first) after that.

In order to obtain a CDL, you will be required to pass a pre-trip vehicle inspection test. You will be tested to see if you know whether your vehicle is safe to drive. You will be asked to do a pre-trip inspection of your vehicle and explain to the examiner what you would inspect and why.

A pre-trip inspection should be done the same way each time so you will learn all the steps and be less likely to forget something. Section 10 of this handbook tells you what to inspect and how to inspect it.

After-Trip Inspection And Report

You must make a written report each day on the condition of the vehicle(s) you drive. Report anything affecting safety which could lead to a mechanical breakdown.

The vehicle inspection report tells the vehicle owner about problems that may need repair. Keep a copy of your report in the vehicle for one day. That way, the next driver can learn about any problems you have found.

Basic Vehicle Control

To drive a vehicle safely, you must be able to control its speed and direction. Safely operating a commercial vehicle requires skill in:

• Accelerating
• Steering
• Backing safely
• Shifting gears
• Braking/controlling speed

Fasten your seat belt when on the road. Apply the parking brake when you leave your vehicle.

Accelerating

Don't roll back when you start. You may hit someone behind you. Partly engage the clutch before you take your right foot off the brake. Set the parking brake whenever necessary to keep from rolling backward. Release it only when you have applied enough engine power to keep from rolling backward. On a tractor-trailer equipped with a trailer brake hand valve, the hand valve can be applied to keep from rolling backward.

Speed up smoothly and gradually so the vehicle does not jerk. Rough acceleration can cause damage to the coupling when pulling a trailer. It is also a common cause of passenger injuries on buses.

Speed up very gradually when traction is poor, as in rain or snow. If you give the vehicle too much power, the drive wheels may spin and you could lose control. If the drive wheels begin to spin, take your foot off the accelerator

Steering

Hold the wheel firmly with both hands. Your hands should be on opposite sides of the wheel. If you hit a curb or a pothole, the wheel could pull away from your hands unless you have a firm hold.

Backing Safely

Because you cannot see everything behind your vehicle, backing is always dangerous. Avoid backing whenever you can. When you park, try to park so you will be able to pull forward when you leave. When you have to back, here are a few simple safety rules:

• Look at your path.
• Back slowly, using your mirrors.
• Back and turn toward the driver's side whenever possible.
• Use a helper whenever possible.

Look at Your Path. Look at your line of travel before you begin. Get out and walk around the vehicle. Check your clearance to the sides and overhead in and near the path your vehicle will take.

Back Slowly. Always back as slowly as possible. Use the lowest reverse gear so that you can easily correct any steering errors before you get too far off course. You can also stop quickly if necessary.

Back and Turn Toward the Driver's Side. Back to the driver’s side so you can see better. Backing toward the right side is very dangerous because you cannot see as well.

Remember to always back in the direction that gives you the best vision.

Backing With A Trailer

Backing with a Trailer. When backing a car, straight truck, or bus, turn the steering wheel toward the direction you want to go. When backing a trailer, turn the steering wheel in the opposite direction. Once the trailer starts to turn, you must turn the wheel the other way to follow the trailer.

Whenever you back with a trailer, try to position your vehicle so you can back in a straight line. If you must back on a curved path, back to the driver’s side so you can see. Back slowly so you can make corrections before you get too far off course.

Use the Mirrors. The mirrors will help you see whether the trailer is drifting to one side or the other.

Correct Drift Immediately. As soon as you see the trailer getting off the proper path, correct it by turning the steering wheel in the direction of the drift.

Pull Forward. When backing, make pull-ups to reposition your vehicle when needed.

Use a Helper. Use a helper when you can. He or she can see blind spots that you can’t. The helper should stand near the back of the vehicle where you can see him or her. Before you begin backing, work out a set of hand signals that you both understand. Agree on a signal for STOP.

Shifting Gears

Shifting gears correctly is important. If you can’t get your vehicle into the correct gear while driving, you will have less control.

Manual Transmissions

Basic Method for Shifting Up. Most heavy vehicles with manual transmissions require double clutching to change gears. This is the basic method:

• Release accelerator, push in clutch, and shift to neutral at the same time.
• Release clutch.
• Let engine and gears slow down to the revolutions per minute (rpm) required for the next gear (this takes practice).
• Push in clutch and shift to the higher gear at the same time.
• Release clutch and press accelerator at the same time.

There are two ways of knowing when to shift:

• Engine speed or rpm. Study the owner’s manual for your vehicle and learn the operating rpm range. Watch your tachometer, and shift up when your engine reaches the top of the range. (Some newer vehicles use “progressive” shifting: the rpm at which you shift becomes higher as you move up in the gears. Find out what is right for your vehicle.)
• Road speed or miles per hour (mph). Learn the correct speed for each gear. Then, by using the speedometer, you will know when to shift up.

With either method, you may learn to use engine sounds to know when to shift.

Basic Procedures for Shifting Down

• Release accelerator, push in clutch, and shift to neutral at the same time.
• Release clutch.
• Press accelerator. Increase engine and gear speed to the rpm required in the lower gear.
• Push in clutch and shift to lower gear at the same time.
• Release clutch and press accelerator at the same time.

Downshifting, like upshifting, requires knowing when to shift. Use either the tachometer or the speedometer and downshift at the right rpm or road speed. Some special conditions where you should downshift are:

• Before starting down a hill. Slow down and shift down to a speed that you can control without using the brakes hard. Otherwise the brakes can overheat and lose their braking power. Downshift before starting down the hill. Make sure you are in a low enough gear, usually lower than the gear required to climb the same hill. The braking effect of the engine is greatest when it is near the governed rpms and the transmission is in the lower gears. Save your brakes so you will be able to stop or slow as required by road and traffic conditions.
• Before entering a curve. Slow down to a safe speed, and downshift before entering the curve. This lets you use some power through the curve to help the vehicle be more stable while turning. It also lets you speed up as soon as you are out of the curve.

Multispeed Rear Axles And Auxiliary Transmissions

Multispeed rear axles and auxiliary transmissions are used on many vehicles to provide extra gears. You usually control them by a selector knob or switch on the gearshift lever of the main transmission. There are many different shift patterns. Learn the right way to shift gears in the vehicle(s) you drive.

Automatic Transmissions

Some vehicles have automatic transmissions which let you select a low range for greater engine braking when going down grades. The lower ranges prevent the transmission from shifting up beyond the selected gear (unless the governor rpm is exceeded). It is very important to use this braking effect when going down grades.

Automated Transmissions

Automated transmissions combine the convenience of an automatic transmission with the control of a manual transmission. An automated transmission has a clutch and gear selection lever. However, the only time the clutch is used is to start and stop the vehicle. Once the vehicle is started, sensors constantly monitor the vehicle’s speed and rpms. Gear shifting is automatic. DMV imposes a restriction when a vehicle equipped with an automated transmission is used for a driving test (because the clutch is only used to start or stop the vehicle).

Retarders

Some vehicles have “retarders.” Retarders help slow a vehicle, reducing the need for using your brakes. They reduce brake wear and give you another way to slow down. There are many types of retarders (exhaust, engine, hydraulic, electric). All retarders can be turned on or off by the driver. On some vehicles the retarding power can be adjusted. When turned “on,” retarders apply braking power to the drive wheels only whenever you let up on the accelerator pedal all the way.

Caution. When the drive wheels have poor traction, the retarder may cause them to skid. You should turn the retarder off whenever the road is wet, icy, or snowy.

Seeing

To be a safe driver and to help avoid accidents, you need to know what is going on all around your vehicle. Not looking properly is a major cause of accidents. All drivers look ahead; but many do not look far enough ahead.

Seeing Ahead

Importance of Looking Far Enough Ahead. Because stopping or changing lanes can take a lot of distance, knowing what traffic is doing on all sides of you is very important. You need to look well ahead to make sure you have room to make these moves safely.

How Far Ahead to Look. Most good drivers look 12 to 15 seconds ahead. That means looking ahead the distance you will travel in 12 to 15 seconds. At lower speeds, that is about one block. At highway speeds, it is about a quarter of a mile. If you are not looking that far ahead, you may have to stop too quickly or make quick lane changes. Looking 12 to 15 seconds ahead does not mean that you should not pay attention to things that are closer. Good drivers shift their attention back and forth, near and far.

What to Look For in Traffic. Be especially alert when nearing freeway on ramps. Look for vehicles entering the highway or moving into your lane or turning. Watch for brake lights of vehicles ahead. By looking far enough ahead you can change your speed or change lanes if necessary to avoid a problem.

Road Conditions. Look for hills and curves– anything for which you will have to slow or change lanes. Pay attention to traffic signals and signs. If a light has been green for a long time, it will probably change before you get there. Start slowing down and be ready to stop. Traffic signs may alert you to road conditions where you may have to change speed.

Seeing Behind And To The Sides

It is important to know what is going on behind and to the sides. Check your mirrors regularly. Check more often in special situations.

Every California registered motor vehicle must have at least two mirrors, including one attached to the left-hand side, and located to give a clear view of the roadway to the rear for a distance of at least 200 feet. Both left- and right-hand rear view mirrors are required on a motor vehicle which is constructed or loaded to obscure the driver’s view to the rear, or which is towing a vehicle or load which blocks the view. (VC §26709)

Mirror Adjustment. Mirror adjustment should be checked prior to the start of any trip and can only be checked accurately when the trailer(s) are straight. You should check and adjust each mirror as needed.

How to Use Mirrors. Use mirrors correctly by quickly checking them often and understanding what you see. When you use your mirrors while driving on the road, check quickly. Look back and forth between the mirrors and the road ahead. Do not focus on the mirrors for too long. Otherwise, you will travel quite a distance without knowing what is happening ahead.

Many large vehicles have curved (convex, “fisheye,” “spot,” “bugeye”) mirrors that show a wider area than flat mirrors. This is often helpful. But remember, everything appears smaller in a convex mirror than it would if you were looking at it directly. Also, things seem farther away than they really are. It is important to realize this and to allow for it.

Regular Checks. You need to make regular checks of your mirrors to be aware of traffic and to check your vehicle.

Traffic. Check the mirrors for vehicles on either side and in back of you. In an emergency, you will need to know whether you can make a quick lane change or stop. Use your mirrors to spot overtaking vehicles. Remember, there are blind spots that your mirrors cannot show you. Check your mirrors regularly to know where other vehicles are around you and to see if they move into your blind spots.

Check your vehicle. Use the mirrors to keep an eye on your tires, it is one way to spot a tire fire. Use the mirrors to check open cargo. Look for loose straps, ropes, or chains. Watch for a flapping or ballooning tarp.

Special Situations. Special situations require more than regular mirror checks. These are lane changes, turns, merges, and tight maneuvers.

Lane changes. Check your mirror to make sure no vehicle is alongside you or about to pass you. Check your mirrors:

• Before you change lanes to make sure there is enough room and signal at least 100 feet before turning. On the freeway, it is best to signal at least five seconds before changing lanes.
• After you have signaled, check to see that the lane is clear and no one has moved into your blind spot.
• Right after you start the lane change to double check that your path is clear.
• After you complete the lane change to be sure you turned off your signal lights.

Turns. When turning, check your mirrors to make sure the rear of your vehicle will not hit anything.

Merges. When merging, use your mirrors to make sure the gap in traffic is large enough for you to enter safely.

Tight Maneuvers. Any time you are driving in close quarters, check your mirrors often. Make sure you have enough clearance for any maneuver you wish to make.

Communicating

Other drivers will not know what you are going to do until you tell them.

Signal Your Intentions

Signaling what you intend to do is important for everyone’s safety. Here are some general rules for signaling.

Turns. There are three good rules for using turn signals:

1. Signal early. Signal several seconds before you turn. It is the best way to keep others from trying to pass you.
2. Signal continuously. You need both hands on the wheel to turn safely. Do not cancel the signal until you have completed the turn.
3. Cancel your signal. Turn the signal off after you have turned.

For information on vehicles which must be equipped with lamp turn signal systems and two stop lamps see VC §§24951 and 24600.

Lane Changes. Use your turn signal before changing lanes. Change lanes slowly and smoothly. That way a driver you did not see may have a chance to avoid your vehicle.

Slowing Down. Warn drivers behind you when you need to slow down. A few light taps on the brake pedal–enough to flash the brake lights– should warn following drivers. Use the 4-way flashers when you are stopped. Warn other drivers in any of the following situations:

• Trouble ahead. The size of your vehicle may make it hard for drivers behind you to see hazards ahead of you. If you see a hazard that will require slowing down, warn the drivers behind by flashing your brake lights.
• Tight turns. Most passenger vehicle drivers do not know how slow you must go to make a tight turn in a large vehicle. Give drivers behind you warning by braking early and slowing gradually.
• Stopping on the road. Truck and bus drivers sometimes stop in the road to unload cargo or passengers or to stop at a railroad crossing. Warn other drivers by flashing your brake lights. Do not stop suddenly.

Don't Direct Traffic. Some drivers try to help out others by signaling when it is safe to pass. You should not do this. You could cause an accident and be held liable for the costs.

Communicating Your Presence

Other drivers may not notice your vehicle even when it is in plain sight. Let them know you are there to help prevent accidents.

When Passing. Whenever you are about to pass a vehicle, pedestrian, motorcyclist, or bicyclist, assume they do not see you. They could suddenly move in front of you. When it is legal, tap the horn lightly or, at night, quickly flash your lights from low to high beam and back. Drive carefully enough to avoid an accident even if they don’t see or hear you.

When it is Hard to See. At dawn or dusk or in rain or snow, you need to make your vehicle easier to see. If you are having trouble seeing other vehicles, other drivers will have trouble seeing you. Turn on your lights. Use the headlights, not just the identification or clearance lights. Use the low beams; high beams can bother people at dawn or dusk as well as at night.

When Parked at the Side of the Road. When you pull off the road and stop, be sure to turn on the 4-way flashers. This is very important at night. Do not trust the taillights to give warning. Drivers have crashed into the rear of a parked truck because they thought it was moving.

If you must stop on the road or the shoulder of a road, put out your reflective triangles within ten minutes. Place your warning devices at the following locations:

• On a two-lane road with traffic in both directions or on an undivided highway, place warning devices within ten feet of the front or rear corners to mark the location of the vehicle and 100 feet behind and ahead of the vehicle, on the shoulder or in the lane in which you stopped. (Figure 2-5)
• On the traffic side of the vehicle, within ten feet of the front or rear corners, to mark the location of the vehicle. (Figure 2-5)
• About 100 feet behind and ahead of the vehicle, on the shoulder or in the lane where you are in. (Figure 2-6)
• Back beyond any hill, curve, or other obstruction that prevents other drivers from seeing the vehicle within 500 feet. (Figure 2-6)
• If you must stop on or by a one-way or divided highway, place warning devices 10 feet, 100 feet, and 200 feet toward the approaching traffic. (Figure 2-7)

Carry the triangles with the reflective side toward the oncoming traffic when placing them, for your own safety. The other drivers will be able to see you.

 

Use Your Horn Only When Needed. Your horn can let others know you are there and can help avoid an accident. However, it can also startle others and could be dangerous if used unnecessarily.

Controlling Speed

Driving too fast is a major cause of fatal crashes. You must adjust your speed depending on several conditions which include: traction, curves, visibility, traffic, and hills.

Speed And Stopping Distances

There are three things that add up to total stopping distance: Perception Distance + Reaction Distance + Braking Distance = Total Stopping Distance.

• Perception distance. This is the distance your vehicle moves from the time your eyes see a hazard until your brain knows it. The perception time for an alert driver is about 3/4 second. At 55 mph you travel 60 feet in 3/4 second.
• Reaction distance. The distance traveled from the time your brain tells your foot to move from the accelerator until your foot is actually pushing the brake pedal. The average driver has a reaction time of 3/4 second. This accounts for an additional 60 feet traveled at 55 mph..
• Braking distance. The distance it takes to stop once the brakes are put on. At 55 mph on dry pavement with good brakes, it can take a heavy vehicle about 170 feet to stop. (About 4 3/4 seconds.)
• Total stopping distance. At 55 mph it will take about 6 seconds to stop and your vehicle will travel about the distance of a football field (60 + 60 + 170 = 290 feet). Refer to Section 5 for more information about stopping distances with air brakes.

Control and Stopping Requirements. (VC §26454) The service brake must hold the vehicle or combination of vehicles stationary on any grade on which it is operated under all conditions of loading or unloading.

The service brakes of every motor vehicle or combination of vehicles must be capable of stopping from an initial speed of 20 miles per hour as follows MSD (Maximum Stopping Distance in feet):

• Passenger vehicle—25 MSD
• Single motor vehicle with manufacturer's GVWR of less than 10,000 pounds—30 MSD
• Single motor vehicle with manufacturer's GVWR of 10,000 pounds or more, or any bus—40 MSD
• Combination of vehicles consisting of a passenger vehicle or any motor vehicle with a manufacturer's GVWR of less than 10,000 pounds in combination with any trailer, semitrailer, or trailer coach—40 MSD
• All other combinations of vehicles—50 MSD

The effect of speed on stopping distance. When you double your speed, it will take about four times the distance to stop and the vehicle will have four times the destructive power if it crashes. High speeds increase stopping distances greatly. By slowing down a little, you can gain a lot in reduced braking distance.

The effect of vehicle weight on stopping distance. If a vehicle is heavier, brakes have to work harder (and absorb more heat) to stop. The brakes, tires, springs, and shock absorbers on heavy vehicles are designed to work best when the vehicle is fully loaded. Generally, empty trucks require greater stopping distances because an empty vehicle has less traction. It can bounce and lock up its wheels, giving much poorer braking. (This is not usually the case with buses.)

Matching Speed To The Road Surface

You cannot steer or brake a vehicle unless you have traction. Traction is friction between the tires and the road. These are some of the road conditions which reduce traction and call for lower speeds:

Slippery Surfaces. It will take longer to stop and it will be harder to turn without skidding when the road is slippery. You must drive slower to be able to stop in the same distance as on a dry road. Wet roads can double the stopping distance. Reduce speed by about one third (i.e., slow from 55 mph to about 35 mph) on a wet road. On packed snow, reduce speed by half, or more. If the surface is icy, reduce speed to a crawl and stop driving as soon as you can safely do so to install chains, if necessary.

Sometimes it is difficult to know if the road is slippery. Here are some examples of slippery roads:

• Shaded areas. Shady parts of the road will remain icy and slippery long after open areas have melted.
• Bridges. When the temperature drops, bridges will freeze before the road will. Be especially careful when the temperature is close to 32° F.
• Melting ice. Slight melting will make ice wet. Wet ice is much more slippery than ice that is not wet.
• Black ice. Black ice is a thin layer that is so clear you can see the road underneath it. It makes the road look wet. Any time the temperature is below freezing and the road looks wet, watch out for black ice.
• Vehicle icing. An easy way to check for ice is to open the window and feel the front of the mirror, mirror support, or antenna. If there is ice on the mirror, the road surface is probably starting to ice up.
• Just after rain begins. Right after it starts to rain, the water mixes with oil left on the road by vehicles. This makes the road very slippery. If it continues, it will wash the oil away.

Hydroplaning. In some weather, water or slush collects on the road. When this happens, your vehicle can hydroplane. It is like water skiing; the tires lose their contact with the road and have little or no traction. You may not be able to steer or brake. You can regain control by releasing the accelerator and pushing in the clutch. This will slow your vehicle and let the wheels turn freely. If the vehicle is hydroplaning, do not use the brakes to slow down. If the drive wheels start to skid, push in the clutch to let them turn freely.

It does not take a lot of water to cause hydroplaning. Hydroplaning can occur at speeds as low as 30 mph if there is a lot of water. It is more likely to occur if tire pressure is low or the tread is worn. (The grooves in a tire carry away the water; if they aren’t deep, they don’t work well.) Be especially careful driving through puddles. Puddles are often deep enough to cause hydroplaning.

Speed And Curves

Drivers must adjust their speed for curves in the road. If you take a curve too fast, two things can happen. The tires can lose their traction and continue straight ahead, so you skid off the road. Or, the tires may keep their traction and the vehicle will roll over. Tests have shown that trucks with a high center of gravity can roll over traveling at the posted speed limit for the curve.

Slow to a safe speed before you enter a curve. Braking in a curve is dangerous because it is easier to lock the wheels and cause a skid. Slow down as needed–never exceed the posted speed limit for the curve. (The speed zone signs posted at curves are for smaller vehicles.) Drive in a gear that will let you accelerate slightly in the curve. This will help you keep control.

Speed And Distance Ahead

You should always be able to stop within the distance you can see ahead. At night, low beams let you see about 250 feet ahead. During the day, fog, rain, or other conditions may require that you slow down to be able to stop in the distance you can see.

Speed And Traffic Flow

When you are driving in heavy traffic, the safest speed is that of other vehicles. Vehicles going the same direction at the same speed are not likely to run into one another. Drive at the speed of the traffic, if you can do so without traveling at an illegal or unsafe speed. Keep a safe following distance.

The main reason drivers exceed speed limits is to save time. But anyone trying to drive faster than the speed of traffic will not be able to save much time. The risks involved are not worth it. Go with the flow of traffic–it is safer and easier. If you go faster than the speed of other traffic:

• You will have to keep passing other vehicles. This increases the chance of an accident.
• It is more tiring. Fatigue increases the chance of an accident.

Overtaking or Following Another Vehicle. You may not overtake and pass another vehicle which is moving at less than 20 mph on a grade (outside a business or residential district) unless you can pass that vehicle at least 10 mph faster than it is traveling and the pass can be completed within one quarter mile. (VC §21758)

You must not follow the vehicles listed below any closer than 300 feet. The rule does not apply during overtaking and passing, when there are two or more lanes for traffic in each direction, or in a business or residential district. (VC §21704)

• A motor truck or truck tractor having three or more axles or any motor truck or truck tractor towing any other vehicle.
• A passenger vehicle or bus towing any other vehicle.
• A school bus transporting any school pupil.
• A farm labor vehicle when transporting passengers.
• A vehicle transporting explosives.
• A trailer bus.

When large vehicles are being driven in caravan on the open highway, at least 100 feet must be left between them to allow other vehicles to overtake and pass them. (VC §21705)

Speed On Downgrades

Your vehicle’s speed will increase on down grades because of gravity. Your most important objective is to select and maintain a speed that is not too fast for the:

• Total weight of the vehicle and cargo.
• Length and steepness of the grade.
• Road conditions and weather.

If a speed limit is posted, or there is a sign indicating a maximum safe speed, never exceed the posted speed. Also look for and heed warning signs indicating the length and steepness of the grade. You must use the braking effect of the engine as the principal way of controlling your speed on downgrades. The braking effect of the engine is greatest when it is near the governed rpms and the transmission is in the lower gears. Save your brakes so you will be able to slow or stop as required by road and traffic conditions.

Slow the vehicle and shift your transmission to a low gear before starting down the grade and use the proper braking techniques.

More information on going down steep hills safely can be found here in the section on "Mountain Driving."

Managing Space

A safe driver keeps space all around the vehicle. When things go wrong, space gives you time to think and to take action.

To have space available when something goes wrong, you need to manage space. While this is true for all drivers, it is very important for large vehicles. They take up more space and they require more space for stopping and turning.

Space Ahead

Of all the space around your vehicle, it is the area ahead of the vehicle–the space you are driving into–that is the most important.

The Need for Space Ahead. You need space ahead in case you must suddenly stop. According to accident reports, the vehicle that trucks and buses most often run into is the one in front of them. The most frequent cause of accidents is following too closely. Remember, if the vehicle ahead of you is smaller than yours, it can probably stop faster than you can. You may crash into it if you are following too closely.

How Much Space? How much space should you keep in front of you? One good rule says you need at least one second for each 10 feet of vehicle length at speeds below 40 mph. At higher speeds, you must add one second for safety. For example, if you are driving a 40foot vehicle, you should leave 4 seconds between you and the vehicle ahead. In a 60foot rig, you will need 6 seconds. Over 40 mph, you would need 5 seconds for a 40-foot vehicle and 7 seconds for a 60-foot vehicle.

To know how much space you have, wait until the vehicle ahead passes a shadow on the road, a pavement marking, or some other obvious landmark. Then count off the seconds like this: “one thousand-and-one, one thousand-and-two” and so on, until you reach the same spot. Compare your count with the rule of one second for every 10 feet of length. If you are driving a 40-foot truck and only counted up to 2 seconds, you are too close. Drop back a little and count again until you have 4 seconds of following distance (or 5 seconds, if you are going over 40 mph). After a little practice, you will know how far back you should be. Remember to add one second for speeds above 40 mph. Also remember that when the road is slippery, you need much more space to stop.

Space Behind

You cannot stop others from following you too closely. But there are things you can do to make it safer.

Stay to the Right. Heavy vehicles are often tailgated when they cannot keep up with the speed of traffic such as when you are going uphill. If a heavy load is slowing you down, stay in the right lane if you can. Going uphill, you should not pass another slow vehicle unless you can get around it quickly and safely.

Handle Tailgaters Safely. In a large vehicle, it is often hard to see whether a vehicle is close behind you. You may be tailgated:

• When you are traveling slowly. Drivers trapped behind slow vehicles often follow too closely.
• In bad weather many passenger vehicle drivers follow large vehicles closely, especially when it is hard to see the road ahead.

If you find yourself being tailgated, here are some things you can do to reduce the chances of an accident:

• Avoid quick changes. If you have to slow down or turn, signal early and reduce speed very gradually.
• Increase your following distance. Opening up room in front of you will help you to avoid having to make sudden speed or direction changes. It also makes it easier for the tailgater to get around you.
• Do not speed up. It is safer to be tailgated at a low speed than a high speed.
• Avoid tricks. Do not turn on your taillights or flash your brake lights. Follow the suggestions above to avoid accidents.

When you follow too closely and another driver “cuts” in front of you, the normal reaction is to slam on your brakes and swerve out of the way. Swerving out of the way can often result in cutting someone else off, possibly driving off the roadway, or driving into another lane of traffic. It might also result in the vehicle behind you crashing into you or other vehicles around you.

If another driver “cuts” in front of you, it is better to take your foot off the gas. This creates space between your vehicle and the other driver without swerving into another lane. Do not overreact if you are cut off. Plan your emergency escape route before the emergency happens.

Space To The Sides

Commercial vehicles are often wide and take up most of a lane. Safe drivers will manage what little space they have. You can do this by keeping your vehicle centered in your lane, and avoid driving alongside other vehicles.

Staying Centered in a Lane. Keep your vehicle centered in the lane to keep safe clearance on either side. If your vehicle is wide, you have little room to spare.

Traveling Next to Others. There are two dangers in traveling alongside other vehicles:

• Another driver may change lanes suddenly and turn into you.
• You may be trapped when you need to change lanes.

Find an open spot where you are not near other traffic. When traffic is heavy, it may be hard to find an open spot. If you must travel near other vehicles, try to keep as much space as possible between you and them. Also, drop back or pull forward so that you are sure the other driver can see you.

Strong Winds. Strong winds make it difficult to stay in your lane. The problem is usually worse for lighter vehicles. This problem can be especially bad coming out of tunnels. Do not drive alongside others if you can avoid it.

Space Overhead

Hitting overhead objects is a danger. Know the overhead clearance of the vehicle you are driving.

• Do not assume that the heights posted at bridges and overpasses are correct. Repaving or packed snow may have reduced the clearances since the heights were posted.
• The weight of a cargo van changes its height. An empty van is higher than a loaded one. Because you cleared a bridge when you were loaded does not mean that you can do it when you are empty.
• If you doubt you have safe space to pass under an object, go slowly. If you are not sure you can make it, do not try it. Take another route. Warnings are often posted on low bridges or underpasses, but sometimes they are not.
• Some roads can cause a vehicle to tilt. There can be a problem clearing objects along the edge of the road, such as signs or trees. Where this is a problem, drive a little closer to the center of the road.
• Before you back into an area, get out and check for overhanging objects such as trees, branches, or electric wires. It is easy to miss seeing them while you are backing. (Also check for other hazards at the same time.)

Space Below

Many drivers forget about the space under their vehicles. That space can be very small when a vehicle is heavily loaded. Railroad tracks can stick up several inches. This is often a problem on dirt roads and in unpaved yards where the surface around the tracks can wear away. Do not take a chance on getting hung up. Drainage channels across roads can cause some vehicles to drag. Cross such depressions carefully.

Space For Turns

The space around a truck or bus is important when turning. Because of wide turning and offtracking, large vehicles can hit other vehicles or objects during turns.

Right turns. Here are some rules to help prevent right turn accidents:

• Turn slowly to give yourself and others more time to avoid problems.
• If you are driving a truck or bus that cannot make a right turn without swinging into another lane, turn wide as you complete the turn as shown in Figure 2-8. Keep the rear of your vehicle close to the curb. This will stop other drivers from passing you on the right.
• Do not turn wide to the left as you start the turn. A following driver may think you are turning left and try to pass you on the right. You may hit the other vehicle as you complete your turn.
• If you must cross into the oncoming lane to make a turn, look for vehicles coming toward you. Give them room to go by or to stop. However, do not back up for them, because you might hit someone behind you.

Left turns. Make sure you have reached the center of the intersection before you start a left turn. If you turn too soon, the left side of your vehicle may hit another vehicle because of offtracking. If you are turning into a multilane street, enter any lane that is safe and available to you.

If there are two turning lanes, you should use the right-hand turn lane as shown in Figure 2-9, because you may have to swing right to make the turn. Drivers on your right may be hard for you to see.

Space To Cross Or Enter Traffic

Be aware of the size and weight of your vehicle when you cross or enter traffic. Here are some important things to keep in mind:

• Because of slow acceleration and the space large vehicles require, you need a much larger gap to enter traffic than you would in a smaller vehicle.
• Acceleration varies with the load. Allow more room if your vehicle is heavily loaded.
• Before you start across a road, make sure you can get all the way across before cross traffic reaches you. It is against the law to enter an intersection if you cannot get completely across before the light changes.

Driving At Night

More than half of all traffic accidents happen at night. Drivers cannot see hazards as soon as in daylight, so they have less time to respond. Drivers caught by surprise are less able to avoid a crash. The problems of night driving involve the driver, the roadway, and the vehicle.

Human Factors

Vision. People cannot see as well at night or in dim light. Also, the eyes need time to adjust to seeing in dim light.

Glare. Drivers can be blinded for a short time by bright light. It can take several seconds to recover from glare. Even two seconds of glare blindness can be dangerous. A vehicle going 55 mph will travel more than half the distance of a football field during that time. Do not look directly at bright lights when driving. Look at the right-hand edge of the road or your traffic lane.

Fatigue and Lack of Alertness. Fatigue and lack of alertness are bigger problems at night. The body naturally wants to sleep. Most drivers are less alert at night, especially after midnight. This is particularly true if you have been driving for a long time. Drivers may not see hazards as soon or react as quickly, so the chance of an accident is greater. If you are sleepy, the only safe cure is to get off the road and get some sleep. If you don’t, you risk your life and the lives of others.

Roadway Factors

Poor Lighting. In the daytime there is usually enough light to see well. This is not true at night. Some areas may have bright street lights, but many areas will have poor lighting. On most roads you will probably have to depend entirely on your headlights.

Less light means you will not be able to see hazards as well as in daytime. Road users who do not have lights are hard to see. There are many accidents at night involving pedestrians, joggers, bicyclists, or animals that are hard to see.

Even when there are lights, the road scene can be confusing. Traffic signals and hazards can be hard to see against a background of signs, shop windows, and other lights.

When lighting is poor or confusing, drive slowly. Be sure you can stop within your sight distance.

Drivers under the influence. Drivers under the influence of alcohol and/or drugs are a hazard to themselves and to you. Be especially alert around the closing time of bars and taverns. Watch for drivers who have trouble staying in their lane or maintaining speed, stop without reason, or show other signs of driving under the influence of alcohol and/or drugs.

Vehicle Factors

Headlights. At night your headlights will usually be the main source of light for you and for others to see you. You cannot see as much with your headlights as you can see in the daytime. With low beams you can see ahead about 250 feet and with high beams about 350–500 feet. You must adjust your speed to keep your stopping distance within your sight distance. This means going slowly enough to be able to stop within the range of your headlights. Otherwise, by the time you see a hazard, you will not have time to stop.

Night driving can be more dangerous if you have problems with your headlights. Dirty headlights may give only half the light they should. This reduces your ability to see, and makes it harder for others to see you. Make sure your lights are clean and working and in adjustment. If out of adjustment, they do not give you a good view and they can blind other drivers.

You must turn on your headlights:

• from a half hour after sunset to a half hour before sunrise, or
• if snow, rain, fog, or other hazardous weather condition requires the use of windshield wipers, or
• when visibility is not sufficient to clearly see a person or a vehicle for a distance of 1,000 feet. (VC §§280 and 24400)
  

No vehicle may be driven with only parking lights on. However, they may be used as signals or when the headlamps are also lighted. (VC §24800)

Other Lights. (VC §25100) In order for you to be seen easily, the following must be clean and working properly:

• Reflectors.
• Marker and clearance lights.
• Taillights.
• Identification lights.

Turn Signals and Brake Lights. At night your turn signals and brake lights are even more important for telling other drivers what you intend to do. Make sure you have clean, working turn signals and stop lights.

Windshields and Mirrors. It is more important at night than in the daytime to have clean windshields and mirrors. Dirt on your windshield or mirrors can cause bright lights at night to create a glare of its own, blocking your view. Clean your windshield on the inside and outside for safe driving.

Night Driving Procedures

Make sure you are rested and alert. If you are drowsy, sleep before you drive. Even a nap can save your life or the lives of others. If you wear eye glasses, make sure they are clean and unscratched. Don’t wear sun glasses at night. Do a complete pre-trip inspection of your vehicle. Pay attention to checking all lights and reflectors and cleaning those you can reach.

Avoid Blinding Others. Glare from your headlights can cause problems for drivers coming toward you as well as drivers going in your direction. Dim your lights within 500 feet of an oncoming vehicle and when following another vehicle within 300 feet.

Avoid Glare from Oncoming Vehicles. Do not look directly at lights of oncoming vehicles. Look slightly to the right at a right lane or edge marking, if available. If other drivers don’t put their low beans on, don’t try to “get back at them” by putting your own high beams on. This increases glare for oncoming drivers and increases the chance of an accident.

Use High Beams When You Can. Many drivers make the mistake of always using low beams. This cuts down on your ability to see ahead. Use high beams when it is safe and legal to do so. Use them unless you are within 500 feet of an approaching vehicle or are following another vehicle within 300 feet. Also, don’t let the inside of your cab get too bright. This makes it harder to see outside. Keep the interior light off and adjust your instrument lights as low as you can and still be able to read the gauges.

If You Get Sleepy, Stop Driving. People often do not realize how close they are to falling asleep. If you look or feel sleepy, stop driving! You are in a very dangerous condition. The only safe cure is to sleep.

Driving In Fog

The best advice for driving in fog is “Don’t.” It is better to pull off the road into a rest area or truck stop, if available, until visibility is better. If you must drive, be sure to consider the following:

• Obey all fog-related warning signs.
• Slow before you enter fog.
• Turn on all your lights. (Headlights should be on low beams.)
• Be prepared for emergency stops.

Driving In Winter

Make sure your vehicle is ready for driving in winter weather. During the pre-trip inspection, pay extra attention to the following items.

Vehicle Checks

Coolant Level and Antifreeze. Make sure the cooling system is full and there is enough antifreeze in the system to protect against freezing. This can be checked with a special coolant tester.

Defrosting and Heating Equipment. Check to see if the defrosters and heaters work. They are needed for safe driving. Make sure you know how to operate them. If you use other heaters and expect to need them (mirror heaters, battery box heaters, fuel tank heaters), check their operation.

Wipers and Washers. The windshield wiper blades must be in good condition. Make sure the wiper blades press against the window hard enough to wipe the windshield clean of snow.

Make sure the windshield washer works and the washer reservoir is full. Use windshield washer antifreeze to prevent freezing of the washer liquid. If you can’t see well enough while driving (i.e., your wipers fail), stop safely and fix the problem.

Tires. Check the tread on your tires. The drive tires must provide traction to push the rig over wet pavement and through snow. The steering tires must have traction to steer the vehicle. Enough tread is especially important in winter conditions. You must have at least 4/32 inch tread depth in every major groove on the front tires and at least 2/32 inch on other tires. More would be better. Use a gauge to determine if you have enough tread for safe driving.

Tire Chains. You may find yourself in conditions where you can’t drive without chains even to get to a place of safety. Carry the correct number of chains and extra cross links. Make sure they will fit your drive tires. Check the chains for broken hooks, worn or broken cross links, and bent or broken side chains. Learn how to put the chains on before you need to do it in snow or ice.

Lights and Reflectors. Make sure the lights and reflectors are clean. Lights and reflectors are especially important during bad weather. Check from time to time during bad weather to make sure they are clean and working.

Windows and Mirrors. Remove any ice, snow, etc. from the windshield, windows, and mirrors before starting. Use a windshield scraper, snow brush, and windshield defroster as necessary.

Handholds, Steps, and Deck Plates. Remove all ice and snow from hand holds, steps, and deck plates which you must use to enter the cab or to move about the vehicle. This will reduce the danger of slipping.

Radiator Shutters and Winterfront. Remove ice from the radiator shutters. Make sure the winterfront is not closed too tightly. If the shutters freeze shut or the winterfront is closed too much, the engine may overheat and stop.

Exhaust System. Exhaust system leaks are especially dangerous when cab ventilation is poor (windows rolled up, etc.). Loose connections can permit poisonous carbon monoxide to leak into your cab which will make you sleepy. In large amounts, it can kill you. Check the exhaust system for loose parts and for sounds and signs of leaks.

Driving On Slippery Surfaces

Slippery Surfaces. Drive slowly and smoothly on slippery roads. If it is very slippery, you shouldn’t drive at all. Stop at the first safe place. The following are some safety guidelines:

• Start gently and slowly. When first starting, get the feel of the road. Do not hurry.
• Adjust turning and braking to conditions. Make turns as carefully as possible. Do not brake any harder than necessary and do not use the engine brake or speed retarder. (They can cause the driving wheels to skid on slippery surfaces.)
• Adjust speed to conditions. Do not pass slower vehicles unless necessary. Go slowly and watch far enough ahead to keep a steady speed. Avoid having to slow down and speed up. Take curves at slower speeds and do not brake while in curves. Be aware that as the temperature rises to the point where ice begins to melt, the road becomes even more slippery and you must slow down even more.
• Adjust space to conditions. Do not drive alongside other vehicles. Keep a greater following distance. When you see a traffic jam ahead, slow down or stop and wait for it to clear. Try to anticipate stops early and slow down gradually.

Wet Brakes. When driving in heavy rain or deep standing water, your brakes will get wet. Water on the brakes can cause the brakes to be weak, to apply unevenly, or to grab. This can cause lack of braking power, wheel lockups, pulling to one side or the other, and a jackknife if you pull a trailer.

Avoid driving through deep puddles or flowing water if possible. If you cannot, you should:

• Slow down.
• Place transmission in a low gear.
• Gently put on the brakes. This presses linings against brake drums or discs and keeps mud, silt, and water from getting in.
• Increase engine rpm and cross the water while keeping light pressure on the brakes.
• When out of the water, maintain light pressure on the brakes for a short distance to heat them up and dry them out.